TS-7180

From embeddedTS Manuals
Note: This manual is incomplete at this time and is subject to change without warning while the TS-7180 is in its Engineering Sampling phase. It is also being updated for Debian 12 (bookworm) and a 5.10 LTS kernel. Please file a support ticket on any questions or issues you encounter in the meanwhile.


TS-7180
ts-7180.gif
Product Page
Product Images
Specifications
Documentation
Schematic
Mechanical Drawing
FTP Path
Processor
NXP i.MX6UL
696 MHz Arm® Cortex®-A7
i.MX6ul Product Page
CPU Documentation

Overview

The TS-7180 is an SBC designed for low power systems and is ideal for remote deployment and fleet tracking.

Getting Started

A Linux workstation is recommended and assumed for development using this documentation. For users in Windows or OSX, we recommend virtualizing Linux using VMWare or similar to make the full power of Linux available. The developer should be comfortable with Linux to work with embedded Linux on the target platform. Most of our platforms run Debian, which is recommended for ease of use if there is no personal distribution preference.

The main reasons that Linux is useful are:

  • Linux filesystems on the microSD card can be accessed on the PC.
  • More ARM cross-compilers are available.
  • If recovery is needed, a bootable medium can be written.
  • A network filesystem can be served.
  • Builds such as Linux kernel, Buildroot, Yocto, and distro-seed will not work from WSL1/2 on a case-insensitive filesystem.
WARNING: Be sure to take appropriate Electrostatic Discharge (ESD) precautions. Disconnect the power source before moving, cabling, or performing setup procedures. Inappropriate handling may cause damage to the board.

Powering up

The TS-7180 typically receives power through a two-pin, 8-28 VDC terminal block connector to the right of the USB-B console connector. From this perspective, the plus (+) side is on the left, and the minus (-) side is on the right. The polarity for the power connection is marked on the enclosure, and is also illustrated in the section on the power connector.

If a power supply is ordered with the TS-7180, it will include the correct terminal block connected to the power supply. Otherwise, the terminal block alone will ship with the unit.

Once power is applied the device will output information via the built in-USB console.

The first output is from the Secondary Program Loader (SPL) and then U-Boot:

U-Boot SPL 2020.01-40207-ge5e6ccfb43 (Feb 07 2022 - 11:26:23 -0700)
Trying to boot from MMC2


U-Boot 2020.01-40207-ge5e6ccfb43 (Feb 07 2022 - 11:26:23 -0700)

CPU:   Freescale i.MX6UL rev1.2 696 MHz (running at 396 MHz)
CPU:   Automotive temperature grade (-40C to 125C) at 44C
Reset cause: WDOG
Model: embeddedTS i.MX6ul TS-7180
DRAM:  1 GiB
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
FPGA:  Rev 15
Net:   eth0: ethernet@20b4000, eth1: ethernet@2188000
Press ESC twice to abort autoboot in 3 second(s)

The SPL, U-Boot and its environment are loaded from the eMMC boot flash (/dev/mmcblk1boot0). This a hardware partition that is independent of the main flash on the eMMC (/dev/mmcblk1). From here, U-Boot runs the script that is in the user-customizable bootcmd environment variable. This by default checks for boot files on the first USB mass storage, SD card, and eMMC. From here the board will boot to our default #Debian image.

The SPL is a tiny, initial stage that U-Boot introduced in recent years to replace the Device Configuration Data block that used to be prepended to U-Boot images. It loads into the CPU's small on-board SRAM and handles early hardware initialization (such as setting up the DRAM controller) required to load the next, larger stage.

Note: U-Boot images or boards with build dates prior to February, 2022 may display differently and/or emit benign error messages such as those below. Typing env save will hide these messages, but doing so is not required to function correctly.

When using U-Boot's default configuration (i.e., if you do not need to modify any setting that U-Boot should honor), the message "*** Warning - bad CRC, using default environment" can be safely ignored. The message indicates that the area(s) of eMMC used for storing the U-Boot environment is uninitialized or has been otherwise overwritten by programs other than U-Boot itself.

The "using MAC address from ROM" warning indicates that the board is using the pre-programmed MAC addresses that are fused into the CPU. All boards are assigned two such unique MAC addresses, so this message is repeated twice. Even with current U-Boots, this message typically appears after a env default -a was run, since that command restores U-Boot's hard-coded environment that lacks board-specific environment variables).

Connect USB Console

The board includes a USB-B header connected to the onboard preprogrammed microcontroller. This acts as a USB serial device using the CP210x Virtual COM port. Most operating systems have built-in support for this device, however drivers are available here.

Console from Linux

There are many serial terminal applications for Linux, three common used applications are picocom, screen, and minicom. These examples demonstrate all three applications and assume that the serial device is "/dev/ttyUSB0" which is common for USB adapters. Be sure to replace the serial device string with that of the device on your workstation.

picocom is a very small and simple client.

sudo picocom -b 115200 /dev/ttyUSB0

screen is a terminal multiplexer which happens to have serial support.

sudo screen /dev/ttyUSB0 115200

Or a very commonly used client is minicom which is quite powerful but requires some setup:

sudo minicom -s
  • Navigate to 'serial port setup'
  • Type "a" and change location of serial device to "/dev/ttyUSB0" then hit "enter"
  • If needed, modify the settings to match this and hit "esc" when done:
     E - Bps/Par/Bits          : 115200 8N1
     F - Hardware Flow Control : No
     G - Software Flow Control : No
  • Navigate to 'Save setup as dfl', hit "enter", and then "esc"

Console from Windows

Putty is a small simple client available for download here. Open up Device Manager to determine your console port. See the putty configuration image for more details.

Device Manager Putty Configuration

First Linux Boot

When booting with the default settings, a shipped board will boot to the eMMC. The eMMC by default are pre-programmed with our default Debian 10 Buster image. After Linux boots it will ask the user to log in with a username and password. This uses "root" as the username with no password. This can be changed after logging in with the command "passwd" to set an account password.

From the Linux prompt you can now begin testing out hardware, or beginning your application development.

U-Boot

U-Boot is a bootloader and comes preinstalled on the TS-7180. U-Boot resides in the eMMC hardware boot partition /dev/mmcblk1boot0. U-Boot sets up the hardware and then loads the OS from the available storage devices. It can boot images from microSD, eMMC, NFS, or USB. Most users will not need to customize U-Boot further, and can proceed to the Debian sections for information on application development.

Entering U-Boot shell

The U-Boot shell provides the ability to run commands directly on the console, and includes commands for modification and saving of the environment (discussed further below).

There are two ways to enter the shell: Pressing the esc key twice within a 1-second window immediately at power-on/reset will bring you to the U-Boot shell prompt. This behavior can be modified by setting the U-Boot environment variable bootdelay. If modified (and saved), it will force the timeout for pressing the esc key to be however many seconds the variable is set to. If it is set to 0, then the esc prompt is skipped, and if set to -1, the sequence will always stop in U-Boot.

The TS-7180 also has a U-Boot jumper. If present, the TS-7180 will always stop in U-Boot. When stopped in U-Boot, booting can be resumed by simply typing boot or run bootcmd.

U-Boot Distro Boot

U-Boot, beginning with its Aug 05 2024 release, is compiled with support for its distro bootcmd scheme to determine how to boot an operating system.

As shipped, and in the absence of removable boot media, the board will boot to our Debian image that is preprogrammed into eMMC.

As configured in the default environment, distro boot looks at:

Order U-Boot device name Description
1 usb0 First detected USB mass storage device
2 mmc0 MicroSD card
3 mmc1 Onboard eMMC storage
4 dhcp DHCP Option [1]
5 pxe PXE File [2]
  1. DHCP can advertise a TFTP server (next-path, root-path, and filename) to point to a U-Boot script.
  2. DHCP can advertise a TFTP server (next-path, root-path, and filename) with a PXE file to control boot.

The default boot order is one that requires no modification to succeed from any supported media. However, boot times can be improved and devices made less susceptible to unintended behavior by stopping at U-Boot and running:

# Boot straight to eMMC:
env set boot_targets 'mmc1';
env save

# Boot to usb, then mmc only
env set boot_targets 'usb0 mmc1';
env save

# Set back to default boot order
env set boot_targets 'usb0 mmc0 mmc1 dhcp pxe'
env save


U-Boot will search MBR-formatted boot media on the 1st partition, or if the media is partitioned with GPT instead, it will search the "bootable" partition[1]. When a boot partition is found, it will then search for these files:

Order Search for Paths Description
1 extlinux /extlinux/extlinux.conf, /boot/extlinux/extlinux.conf Menu conf file of kernels
2 U-Boot script /boot.scr.uimg, /boot.scr, /boot/boot.scr.uimg, /boot/boot.scr U-Boot script with instructions to load the OS
3 EFI Binary efi/boot/bootarm.efi EFI binary (such as grub)

Our Debian images boot via a U-Boot script in /boot/boot.scr.uimg.

U-Boot Environment

The TS-7180 stores its U-Boot environment in the /dev/mmcblk1boot0 partition of its on-board eMMC flash.

# Print all environment variables
env print -a

# Sets the variable bootdelay to 5 seconds
env set bootdelay 5

# Variables can also contain commands
env set hellocmd 'led 0 off; echo Hello world; led 1 on;'

# Execute commands saved in a variable
env run hellocmd

# Commit env changes to the spi flash
# Otherwise changes are lost
env save

# Restore env to default
env default -a

# Remove a variable
env delete hellocmd

U-Boot Commands

# The most important command is 
help
# This can also be used to see more information on a specific command
help i2c

# Boot a Linux zImage loaded at $loadaddr
bootz
# Boot in to a Linux zImage at $loadaddr, skip initrd, specifies
# the FDT address to Linux knows where to find the device tree
bootz ${loadaddr} - ${fdtaddr}

# Get a DHCP address
dhcp
# This sets ${ipaddr}, ${dnsip}, ${gatewayip}, ${netmask}
# and ${ip_dyn} which can be used to check if the dhcp was successful

# These commands are used for scripting:
false # do nothing, unsuccessfully
true # do nothing, successfully

# This command can set fuses in the processor
# Setting fuses can brick the unit, will void the warranty,
# and should not be done in most cases
fuse

# GPIO can be manipulated from U-Boot.  Keep in mind that the IOMUX 
# in U-Boot is only setup enough to boot the device, so not all pins will
# be set to GPIO mode out of the box.  Boot to the full operating system
# for more GPIO support.
# GPIO are specified in bank and IO in this manual.  U-Boot uses a flat numberspace,
# so for bank 2 DIO 25, this would be number (32*1)+25=89
# The formula thus being (32*(bank-1)+dio)=flattened_dio
# Note that on some products, bank 1 is the first bank
# Set 2_25 low
gpio clear 83
# Set 2_25 high
gpio set 83
# Read 2_25
gpio input 83

# This command is used to copy a file from most devices
# Load kernel from SD
load mmc 0:1 ${loadaddr} /boot/zImage
# Load Kernel from eMMC
load mmc 1:1 ${loadaddr} /boot/zImage
# Load kernel from USB
usb start
load usb 0:1 ${loadaddr} /boot/zImage

# View an FDT on a boot image using U-Boot
load mmc 1:1 ${fdtaddr} /boot/imx6ul-ts${model}.dtb
fdt addr ${fdtaddr}
fdt print

# It is possible to blindly jump to any memory location
# This is similar to bootm, but it does not require
# the use of the U-Boot header
load mmc 0:1 ${loadaddr} /boot/custombinary
go ${loadaddr}

# Browse fat, ext2, ext3, or ext4 filesystems on an SD card:
ls mmc 0:1 /

# Test memory.
mtest

# Check for new SD card
mmc rescan
# Read SD card size
mmc dev 0
mmcinfo
# Read eMMC Size
mmc dev 1
mmcinfo

# The NFS command is like 'load', but used over the network
dhcp
env set serverip 192.168.0.11
nfs ${loadaddr} 192.168.0.11:/path/to/somefile

# Test ICMP
dhcp
ping 192.168.0.11

# Reboot
reset

# SPI access is through the SF command
# Be careful with sf commands since
# this is where U-Boot and the FPGA bitstream exist
# Improper use can render the board unbootable
sf probe

# Delay in seconds
sleep 10

# Load HUSH scripts that have been created with mkimage
load mmc 0:1 ${loadaddr} /boot/boot.scr
source ${loadaddr}

# Most commands have return values that can be used to test
# success, and HUSH scripting supports comparisons like
# test in Bash, but much more minimal
if load mmc 1:1 ${fdtaddr} /boot/zImage;
	then echo Loaded Kernel
else
	echo Could not find kernel
fi

# Print U-Boot version/build information
version

Booting From NFS

Note: The following instructions assume the NFS server is running Debian.

U-Boot's NFS support can be used to load a kernel, device tree binary, and root filesystem. The default scripts include an example NFS boot script. Because of the way U-Boot tries to infer server data, the script we use will bypass this, making it more straightforward to use an NFS root that will not be heavily dependent on a particular network configuration.

First, on the NFS server side, be sure to verify and if needed modify /etc/default/nfs-kernel-server such that the server is running NFS -V 2. The nfs-kernel-server file should resemble the following:

# Number of servers to start up
RPCNFSDCOUNT="8 --no-nfs-version 4 -V 2"

# Runtime priority of server (see nice(1))
RPCNFSDPRIORITY=0

# Options for rpc.mountd.
# If you have a port-based firewall, you might want to set up
# a fixed port here using the --port option. For more information, 
# see rpc.mountd(8) or http://wiki.debian.org/SecuringNFS
# To disable NFSv4 on the server, specify '--no-nfs-version 4' here
RPCMOUNTDOPTS="--manage-gids --no-nfs-version 4"

# Do you want to start the svcgssd daemon? It is only required for Kerberos
# exports. Valid alternatives are "yes" and "no"; the default is "no".
NEED_SVCGSSD=""

# Options for rpc.svcgssd.
RPCSVCGSSDOPTS=""

Once verified that the file /etc/default/nfs-kernel-server looks like the above, then from the U-Boot shell run the following commands:

# Set this to your NFS root path
env set nfsroot <IP ADDRESS>:/path/to/nfs/rootfs/
env save

To boot to NFS root once the server details are set:

# Boot to NFS once
run nfsboot;

# To make the NFS boot the persistent default
env set bootcmd run nfsboot;
env save
Note: You must have NFS version 2 on your server, as it is disabled by default on new distributions. Be sure to read the U-Boot Documentation for further details U-Boot Documentation

.

U-Boot Development

Note: This section is incomplete at this time and is subject to change without warning while the TS-7180 is in its Engineering Sampling phase.

We do provide our U-Boot sources, but we do not recommend rebuilding a custom U-Boot binary, as it can leave the system in an unbootable state.

If proceeding with building a custom U-Boot, use the "v2020.01-ts" branch from our github repo: https://github.com/embeddedTS/u-boot-imx this can be executed with the following command:

git clone https://github.com/embeddedTS/u-boot-imx.git -b v2020.01-ts u-boot-ts7250v3

When compiling, we recommend using ONLY this cross-compiler, the use of any other compiler may cause issues or may leave the system in an unbootable state! Specifically, we have experienced RAM problems when using a more recent cross compiler to build this version of U-Boot. The tarball can be extracted with the following:

mkdir /opt/toolchains/ts7250v3/
tar -xf tsimx6ul-glibc-gnueabihf-4.9.4.tar.xz -C /opt/toolchains/ts7250v3/

Once the tarball has been properly extracted set up the following variables and run the build script:

export ARCH=arm
export CROSS_COMPILE=/path/to/folder/bin/arm-linux-gnueabihf-

After the environment variables have been set up as shown above the build is now ready to be executed:

cd /path/to/u-boot-imx
./build-imx6ul.sh ts7250v3

Debian on the TS-7180

Debian 12 - Bookworm

Debian 12 - Getting Started

This Debian release is available in two flavors with various packages.

Image Estimated Size Description
debian-armhf-bookworm-headless-20240417.tar.xz 1.1 GiB
  • Includes 5.10 kernel with a tsimx6ul_defconfig that includes broad driver support
  • Base Debian with common utils
  • Common embedded tools (i2c, can, gpio, iio, serial tools, etc)
  • Includes hardware support
  • Networking tools (ethernet, wifi, bluetooth)
  • Includes Development tools
debian-armhf-bookworm-minimal-latest.tar.bz2 263 MiB
  • Includes 5.10 kernel with tsimx6ul_minimal_defconfig that includes bare minimum driver support and kernel options required by Debian.
  • Includes base Debian rootfs adding only what is required for Ethernet support.

The default login is root with no password.

This image can be written to a USB drive, or to the eMMC. For development, a USB thumbdrive will be simplest. If a bootable USB drive is connected this will take priority over other boot media Plug in a USB drive and check the last output from dmesg(1) to get the USB disk. For example, this may be /dev/sdc.

# Erase all older partitions
sudo sgdisk --zap-all /dev/sdc
# Create one GPT Linux partition
sudo sgdisk -n 0:0:0 -t 0:8300 /dev/sdc
# Create a filesystem and mount
sudo mkfs.ext4 /dev/sdc1
sudo mkdir /mnt/usb/
sudo mount /dev/sdc1 /mnt/usb/
# Extract downloaded image:
sudo tar --numeric-owner --dereference -xf debian-armhf-bookworm-headless-20240417.tar.xz -C /mnt/usb/
sudo chmod 755 /mnt/usb/
sudo umount /mnt/usb/

These commands will also work while booted from a USB drive to rewrite the eMMC. Instead of /dev/sdc you would use /dev/mmcblk1, and instead of /dev/sdc1 you would use /dev/mmcblk1p1. To prepare an SD card, the devices would be /dev/mmcblk0 and /dev/mmcblk0p1, respectively.

Debian 12 - Networking

The network in Debian is configured with /etc/network/interfaces. For complete documentation, see Debian's documentation here

Some common examples are shown below. On this release network interfaces follow the predictible network interface names. Run ip addr show to get a list of the network interfaces.

Most commonly:

  • end0 - Ethernet device 0 (CPU Ethernet)
  • enp1s0 - Ethernet PCIe port 1 slot 0 ethernet
  • usb<mac> - USB ethernet
  • wlan0 - WIFI

DHCP on end0. Edit the file /etc/network/interfaces and add:

auto end0
allow-hotplug end0
iface end0 inet dhcp

Static IP on end0. Edit the file /etc/network/interfaces and add:

auto end0
iface end0 inet static
    address 192.0.2.7/24
    gateway 192.0.2.254

These will take effect on the next boot, or by restarting the networking service:

service networking restart

Debian 12 - WIFI Client

Wireless interfaces are also managed with configuration files in "/etc/network/interfaces.d/". For example, to connect as a client to a WPA network with DHCP. Note some or all of this software may already be installed on the target SBC.

Install wpa_supplicant:

apt-get update && apt-get install wpasupplicant -y

Run:

wpa_passphrase youressid yourpassword

This command will output information similar to:

 network={
 	ssid="youressid"
 	#psk="yourpassword"
 	psk=151790fab3bf3a1751a269618491b54984e192aa19319fc667397d45ec8dee5b
 }

Use the hashed PSK in the specific network interfaces file for added security. Create the file:

/etc/network/interfaces.d/wlan0

allow-hotplug wlan0
iface wlan0 inet dhcp
    wpa-ssid youressid
    wpa-psk 151790fab3bf3a1751a269618491b54984e192aa19319fc667397d45ec8dee5b

To have this take effect immediately:

service networking restart

For more information on configuring Wi-Fi, see Debian's guide here.

Debian 12 - WIFI Access Point

First, hostapd needs to be installed in order to manage the access point on the device:

apt-get update && apt-get install hostapd -y


Note: The install process will start an unconfigured hostapd process. This process must be killed and restarted before a new hostapd.conf will take effect.

Edit /etc/hostapd/hostapd.conf to include the following lines:

interface=wlan0
driver=nl80211
ssid=YourAPName
channel=1
Note: Refer to the kernel's hostapd documentation for more wireless configuration options.


To start the access point launch hostapd:

hostapd /etc/hostapd/hostapd.conf &

This will start up an access point that can be detected by WIFI clients. A DHCP server will likely be desired to assign IP addresses. Refer to Debian's documentation for more details on DHCP configuration.

Debian 12 - Installing New Software

Debian provides the apt-get system which allows management of pre-built applications. The apt tools require a network connection to the internet in order to automatically download and install new software. The update command will download a list of the current versions of pre-built packages.

apt-get update

A common example is installing Java runtime support for a system. Find the package name first with search, and then install it.

root@tsa38x:~# apt-cache search openjdk
default-jdk - Standard Java or Java compatible Development Kit
default-jdk-doc - Standard Java or Java compatible Development Kit (documentation)
default-jdk-headless - Standard Java or Java compatible Development Kit (headless)
default-jre - Standard Java or Java compatible Runtime
default-jre-headless - Standard Java or Java compatible Runtime (headless)
jtreg - Regression Test Harness for the OpenJDK platform
libreoffice - office productivity suite (metapackage)
openjdk-11-dbg - Java runtime based on OpenJDK (debugging symbols)
openjdk-11-demo - Java runtime based on OpenJDK (demos and examples)
openjdk-11-doc - OpenJDK Development Kit (JDK) documentation
openjdk-11-jdk - OpenJDK Development Kit (JDK)
openjdk-11-jdk-headless - OpenJDK Development Kit (JDK) (headless)
openjdk-11-jre - OpenJDK Java runtime, using Hotspot JIT
openjdk-11-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
openjdk-11-jre-zero - Alternative JVM for OpenJDK, using Zero
openjdk-11-source - OpenJDK Development Kit (JDK) source files
uwsgi-app-integration-plugins - plugins for integration of uWSGI and application
uwsgi-plugin-jvm-openjdk-11 - Java plugin for uWSGI (OpenJDK 11)
uwsgi-plugin-jwsgi-openjdk-11 - JWSGI plugin for uWSGI (OpenJDK 11)
uwsgi-plugin-ring-openjdk-11 - Closure/Ring plugin for uWSGI (OpenJDK 11)
uwsgi-plugin-servlet-openjdk-11 - JWSGI plugin for uWSGI (OpenJDK 11)
java-package - Utility for creating Java Debian packages

In this case, the wanted package will likely be the "openjdk-11-jre" package. Names of packages can be found on Debian's wiki pages or the packages site.

With the package name apt-get install can be used to install the prebuilt packages.

apt-get install openjdk-11-jre
# More than one package can be installed at a time.
apt-get install openjdk-11-jre nano vim mplayer

For more information on using apt-get refer to Debian's documentation here.

Debian 12 - Setting up SSH

Openssh is installed in our default Debian image, but by default openssh does not permit root logins, and requires a password to be set. Additionally, a host key is required if one hasn't already been created on the target board. To allow remote root login:

sed --in-place 's/#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config
systemctl restart ssh.service
passwd root # Set any password

If you ssh to this system it will now support ssh as root.

Debian 12 - Starting Automatically

Bookwoorm Startup Scripts

Debian 12 - Cross Compiling

Debian provides cross toolchains within their distribution for different architectures.

For best portability we recommend using a container like docker to run a Debian 12 rootfs for the toolchain. This will allow a consistent toolchain to run from almost any Linux system that can run Docker. Keep in mind that while docker does run under OSX and Windows, these are run under a case insensitive filesystem which will cause problems with complex builds like the Linux kernel so a Linux host is still recommended.

  • Ubuntu/Debian:
sudo apt-get install docker.io -y
  • Fedora
sudo dnf install docker -y

After installing docker on any distribution make sure your user is in the docker group:

# Add your user to the docker group.  You may need to logout/log back in.
sudo usermod -aG docker $USER

Make sure you can run docker's hello world image as your user to verify it is working:

docker run hello-world

Now create a file Dockerfile:

sudo mkdir -p /opt/docker-toolchain/docker-debian-bookworm-armhf
# Use any preferred editor, vim/emacs/nano/etc
sudo nano /opt/docker-toolchain/docker-debian-bookworm-armhf/Dockerfile
# syntax = docker/dockerfile:1.2

FROM debian:bookworm

RUN dpkg --add-architecture armhf

RUN apt-get update && apt-get install -y \
    autogen \
    automake \
    bash \
    bc \
    bison \
    build-essential \
    bzip2 \
    ca-certificates \
    ccache \
    chrpath \
    cpio \
    curl \
    diffstat \
    fakeroot \
    file \
    flex \
    gawk \
    gcc-arm-linux-gnueabihf \
    git \
    gzip \
    kmod \
    libgpiod-dev:armhf \
    libncursesw5-dev \
    libssl-dev \
    libtool \
    libyaml-dev \
    locales \
    lz4 \
    lzop \
    make \
    multistrap \
    ncurses-dev \
    pkg-config \
    python3 \
    python3-cbor \
    python3-pexpect \
    python3-pip \
    qemu-user-static \
    rsync \
    runit \
    socat \
    srecord \
    swig \ 
    texinfo \
    u-boot-tools \
    zstd \
    unzip \
    vim \
    wget \
    xz-utils

# Provide a more friendly name
ENV debian_chroot debian_bookworm
RUN echo "PS1='\${debian_chroot}\\[\033[01;32m\\]@\\H\[\\033[00m\\]:\\[\\033[01;34m\\]\\w\\[\\033[00m\\]\\$ '" >> /etc/bash.bashrc

# Set up locales
RUN sed -i -e 's/# en_US.UTF-8 UTF-8/en_US.UTF-8 UTF-8/' /etc/locale.gen && \
        echo 'LANG="en_US.UTF-8"'>/etc/default/locale && \
        dpkg-reconfigure --frontend=noninteractive locales && \
        update-locale LANG=en_US.UTF-8
ENV LC_ALL en_US.UTF-8
ENV LANG en_US.UTF-8
ENV LANGUAGE en_US.UTF-8

Next make a shell script to enter into this docker container. Create /usr/local/bin/docker-debian-bookworm:

# Use any preferred editor, vim/emacs/nano/etc
sudo nano /usr/local/bin/docker-debian-bookworm
#!/bin/bash -e

# Enters a docker running Debian 12 Bookworm
# Any arguments are run in the docker, or if no arguments it runs a shell

export TAG=debian-bookworm-armdev
SCRIPTPATH=$(readlink -f "$0")
DOCKERPATH=/opt/docker-toolchain/docker-debian-bookworm-armhf/

DOCKER_BUILDKIT=1 docker build --tag "$TAG" "$DOCKERPATH" --quiet

exec docker run --rm \
	-it \
	--volume "$(pwd)":/work \
	--user $(id -g):$(id -u) \
	-w /work \
	-e HOME=/tmp \
	"$TAG" \
	$@;

Make this executable, and call it:

sudo chmod a+x /usr/local/bin/docker-debian-bookworm

# dont run as root
docker-debian-bookworm

The first time this runs it will download a base Debian image, and run the above apt-get commands which may take around 10 or so minutes depending on your internet connection and disk speed. After it has run once, it will stay cached and adds almost no overhead to run.

This docker can be thought of as a very low overhead virtual machine that only has access to the directory where it is run.

For example, to build a simple c project, create a ~/Desktop/hello-world/hello.c:

mkdir -p ~/Desktop/hello-world/

In ~/Desktop/hello-world/hello.c:

#include <stdio.h>

int main() {
    printf("Hello world!\n");
    return 0;
}

We can now use the docker in that directory to use Debian's cross compiler to create a binary that targets armhf:

user@hostname:~$ cd ~/Desktop/hello-world/
user@hostname:~/Desktop/hello-world$ docker-debian-bookworm
sha256:a92e70c3d7346654b34c0442da20ae634901fd25d1a89dd26517e7d1c1d00c47
debian_bookworm@a8ddfa54989f:/work$ ls
hello.c
debian_bookworm@a8ddfa54989f:/work$ arm-linux-gnueabihf-gcc hello.c -o hello
debian_bookworm@a8ddfa54989f:/work$ arm-linux-gnueabihf-strip hello
debian_bookworm@a8ddfa54989f:/work$ file hello
hello: ELF 32-bit LSB pie executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, BuildID[sha1]=ffda981721a1531418ed1da27238707851ae0126, for GNU/Linux 3.2.0, stripped

Debian 12 - Compile the Kernel

A compatible armhf cross compiler is needed for building the 5.10 kernel. We recommend using the cross compiler available in Debian distributions. It is also possible to use our Buildroot repository to build a compatible cross compiler.


Download and Configure

These steps assume a host Linux workstation with an appropriate cross compiler. While on most platforms the kernel can be downloaded, built, and installed all on the device, we recommend against this due to the amount of time, memory, and disk space that can be needed for a build.


Prerequisites

If using our instructions for using Docker to handle the cross compiler, then the Docker environment needs to be entered first:

# Create a place to store the kernel:
mkdir -p ~/Projects/tsimx6ul/kernel/
cd ~/Projects/tsimx6ul/kernel/
docker-debian-bookworm

If the Docker container is not being used, a number of host tools are required to be installed on the workstation:

# Install dependencies for kernel build
# The following command is for Ubuntu / Debian workstations. If using a different
# distribution, please consult distribution docs for the proper commands to install
# new packages/tools/libraries/etc.
apt-get install git fakeroot build-essential ncurses-dev xz-utils lzop libssl-dev bc flex libelf-dev bison
Note: The above prerequisite libraries and tools may not be the complete list, depending on the workstation's distribution and age. It may be necessary to install additional packages to support kernel compilation.

Download kernel repo on a host Linux workstation:

# Do a shallow clone of the sources
git clone --depth 1 -b linux-5.10.y https://github.com/embeddedTS/linux-lts

cd linux-lts/


Configure environment variables needed for building. This specifies the architecture, the cross compiler that is being used, and to set up building the kernel modules for the WILC3000 Wi-Fi/BLE module:

export CROSS_COMPILE=arm-linux-gnueabihf-  # This may be different if using a different compiler!
export ARCH=arm
export WILC=y


The WILC3000 Wi-Fi/BLE drivers are maintained and built externally out of the kernel tree. Clone this tree inside of the linux-lts/ directory (this is built later):

git clone -b linux4microchip-2021.10-1 https://github.com/embeddedTS/wilc3000-external-module/


Next, set the default configuration for this platform. Note that a minimal defconfig and a full-feature defconfig are available. The minimal defconfig contains options for supporting the device and a few common peripherals and technologies. While the full defconfig includes much more support for things like USB devices, a more broad range of netfilter/iptables filter module support, etc.

make tsimx6ul_defconfig

# The minimal defconfig can alternately be used with:
# make tsimx6ul_minimal_defconfig


Build and Install

Note: If using the Docker container to cross compile, be sure to exit the container after the build script below completes! The tarball will be located in the linux-lts/ folder that was created.

The following will build the kernel and modules, and install the kernel, modules, and headers to a folder and create a tarball from that. This tarball can be unpacked to bootable media, e.g. microSD, eMMC, USB, etc., to update an existing bootable disk.

The script below is most easily saved as a text file and run from the command line as a script. Most terminal emulators will accept the whole script copy/pasted in to the terminal. But it is also possible to copy paste each line of text in to a terminal. In any case, the following is an example of how to compile the kernel. The script or commands used can be modified as needed to suit a specific build pipeline.

The script assumes the following environment variables are set before it is run. See the above sections for what these variables should be set to for this specific platform.

ARCH
Used to indicate the target CPU architecture.
CROSS_COMPILE
Used to point to an appropriate cross toolchain for the target platform.
LOADADDR [Optional]
Used on some platforms to tell U-Boot where to load the file.
WILC [Optional]
Set to "y" to build and install the WILC3000 Wi-Fi/BLE external modules.
#!/bin/bash -e

# Always build zImage, most common. If LOADADDR is set, then uImage is also built
TARGETS="zImage"
if [ -n "${LOADADDR}" ]; then TARGETS+=" uImage"; fi

# Build the actual kernel, binary files, and loadable modules.
# Use as many CPUs to do this as possible.
make -j"$(nproc)" && make ${TARGETS} && make modules

# Create a temporary directory to install the kernel to in order to use that as a base directory for a tarball.
# Also creates a temporary file that is used as the tarball name.
TEMPDIR=$(mktemp -d)
TEMPFILE=$(mktemp)
mkdir "${TEMPDIR}/boot/"

# Adds "arch/arm/boot/" path prefix to each TARGET
cp $(for i in ${TARGETS}; do echo arch/arm/boot/$i; done) "${TEMPDIR}"/boot/

# Copy the full .config file to the target, this is optional and can be removed
cp .config "${TEMPDIR}"/boot/config

# Copy all of the generated FDT binary files to the target
find arch/arm/boot/dts -name "*ts*.dtb" -exec cp {} "${TEMPDIR}/boot" \;

# Install kernel modules to the target
INSTALL_MOD_PATH="${TEMPDIR}" make modules_install

# Install kernel headers to the target, this is optional in most cases and can be removed to save space on the target
make headers_install INSTALL_HDR_PATH="${TEMPDIR}"

# If WILC is set to "y", then build the external module for the WILC300 Wi-Fi/BLE device.
# Note that this expects the source to be available as a subfolder in the kernel. See the above sections 
# for details on getting the driver source if it is used on this specific platform.
if [ "${WILC}" == "y" ]; then
    CONFIG_WILC_SPI=m INSTALL_MOD_PATH="${TEMPDIR}" make M=wilc3000-external-module modules modules_install
fi

# Use fakeroot to properly set permissions on the target folder as well as create a tarball from this.
fakeroot sh -c "chmod 755 ${TEMPDIR};
        chown -R root:root ${TEMPDIR};
        tar czf ${TEMPFILE}.tar.gz -C ${TEMPDIR} .";

# Create a final output tarball and cleanup all of the temporary files and folder.
cp ${TEMPFILE}.tar.gz embeddedTS-linux-lts-"$(date +"%Y%m%d")"-"$(git describe --abbrev=8 --dirty --always)".tar.gz
rm -rf "${TEMPDIR}" "${TEMPFILE}"


At this point, the tarball can be unpacked to a bootable media for the device. This can be done from a booted device, or by mounting removable media from a host Linux workstation. For example, if the root folder of the target filesystem to be updated is mounted to /mnt/, the following can be used to unpack the above tarball:

# Ensure the target filesystem is mounted to /mnt first!

# Extract kernel tarball to target filesystem, 
tar xhf embeddedTS-linux-lts-*.tar.gz -C /mnt
Note: The h argument to tar is necessary on recent distributions that use paths with symlinks. Not using it can potentially render the whole filesystem no longer bootable.


This will correctly unpack the kernel, modules, and headers to the target filesystem which can then be booted as normal.


Debian 10

Debian is a community run Linux distribution. Debian provides tens of thousands of precompiled applications and services. This distribution is known for stability and large community providing support and documentation. The installation is specific to our board, but most Debian documentation applies:

Debian 10 - Getting Started and writing an Image

Once installed, the default user is "root" with no password.


This image can be written to a USB drive, a µSD card, or to eMMC. For development, a USB thumbdrive will be simplest. If a bootable USB drive is connected this will take priority over other boot media. Plug in a USB drive and check the last output from "dmesg" to get the USB disk. For example, this may be /dev/sdc.

# Erase all older partitions
sudo sgdisk --zap-all /dev/sdc
# Create one GPT Linux partition
sudo sgdisk -n 0:0:0 -t 0:8300 /dev/sdc
# Create a filesystem and mount
sudo mkfs.ext4 /dev/sdc1
sudo mkdir /mnt/usb/
sudo mount /dev/sdc1 /mnt/usb/
# Extract downloaded image:
sudo tar --numeric-owner -xf ts7180-debian-buster-latest.tar.bz2 -C /mnt/usb/
sudo chmod 755 /mnt/usb/
sudo umount /mnt/usb/

These commands will also work while booted from a USB drive to rewrite the eMMC. Instead of /dev/sdc you would use /dev/mmcblk1, and instead of /dev/sdc1 you would use /dev/mmcblk1p1.

Debian 10 - Configuring the Network

The network in Debian is configured /etc/network/interfaces.d/. For complete documentation, see Debian's documentation here

Some common examples are shown below.

DHCP on eth0. Create the file: /etc/network/interfaces.d/eth0

auto eth0
allow-hotplug eth0
iface eth0 inet dhcp

Static IP on eth0. Create the file /etc/network/interfaces.d/eth0

auto eth0
iface eth0 inet static
    address 192.0.2.7/24
    gateway 192.0.2.254

These will take effect on the next boot, or by restarting the networking service:

service networking restart


Debian 10 - WIFI Client

Note: The latest image for this platform as of April 28th, 2022 has known issues with the Wi-Fi driver due to incompatibility with cfg80211 powersave modes.

If using Wi-Fi, it is strongly recommended to bring up the Wi-Fi interface, and then run iw wlan0 set power_save off to disable powersave modes.

This issue will be addressed in future images and has already been addressed in our kernel sources. We will continue to provide updates as we receive them from the Wi-Fi module manufacturer.

Wireless interfaces are also managed with configuration files in "/etc/network/interfaces.d/". For example, to connect as a client to a WPA network with DHCP. Note some or all of this software may already be installed on the target SBC.

Install wpa_supplicant:

apt-get update && apt-get install wpasupplicant -y

Run:

wpa_passphrase youressid yourpassword

This command will output information similar to:

 network={
 	ssid="youressid"
 	#psk="yourpassword"
 	psk=151790fab3bf3a1751a269618491b54984e192aa19319fc667397d45ec8dee5b
 }

Use the hashed PSK in the specific network interfaces file for added security. Create the file:

/etc/network/interfaces.d/wlan0

allow-hotplug wlan0
iface wlan0 inet dhcp
    wpa-ssid youressid
    wpa-psk 151790fab3bf3a1751a269618491b54984e192aa19319fc667397d45ec8dee5b

To have this take effect immediately:

service networking restart

For more information on configuring Wi-Fi, see Debian's guide here.


Debian 10 - WIFI Access Point

Note: The latest image for this platform as of April 28th, 2022 has known issues with the Wi-Fi driver due to incompatibility with cfg80211 powersave modes.

If using Wi-Fi, it is strongly recommended to bring up the Wi-Fi interface, and then run iw wlan0 set power_save off to disable powersave modes.

This issue will be addressed in future images and has already been addressed in our kernel sources. We will continue to provide updates as we receive them from the Wi-Fi module manufacturer.

First, hostapd needs to be installed in order to manage the access point on the device:

apt-get update && apt-get install hostapd -y


Note: The install process will start an unconfigured hostapd process. This process must be killed and restarted before a new hostapd.conf will take effect.

Edit /etc/hostapd/hostapd.conf to include the following lines:

interface=wlan0
driver=nl80211
ssid=YourAPName
channel=1
Note: Refer to the kernel's hostapd documentation for more wireless configuration options.


To start the access point launch hostapd:

hostapd /etc/hostapd/hostapd.conf &

This will start up an access point that can be detected by WIFI clients. A DHCP server will likely be desired to assign IP addresses. Refer to Debian's documentation for more details on DHCP configuration.


Wi-Fi Concurrent Client / Access Point

Note: The latest image for this platform as of April 28th, 2022 has known issues with the Wi-Fi driver due to incompatibility with cfg80211 powersave modes.

If using Wi-Fi, it is strongly recommended to bring up the Wi-Fi interface, and then run iw wlan0 set power_save off to disable powersave modes.

This issue will be addressed in future images and has already been addressed in our kernel sources. We will continue to provide updates as we receive them from the Wi-Fi module manufacturer.

The Wi-Fi device on this platform supports concurrent operation of client and access point (STA and AP). Please see the "Wi-Fi Client" section above first to connect the Wi-Fi module, in STA mode, to an external AP. This demo showcases the Wi-Fi module starting its own AP mode via hostapd with a simple static IP address while also being concurrently connected to a separate AP.

The 'hostapd' utility is used to manage the access point of the device. This is usually installed by default, but can be installed with:

apt-get update && apt-get install hostapd -y


Note: The install process may start an unconfigured 'hostapd' process. This process must be killed before moving forward.


Modify the file /etc/hostapd/hostapd.conf to have the following lines:

ssid=YourWiFiName
wpa_passphrase=Somepassphrase
interface=p2p0
auth_algs=3
channel=<channel>
driver=nl80211
logger_stdout=-1
logger_stdout_level=2
wpa=2
wpa_key_mgmt=WPA-PSK
Note: The channel used for AP must match the channel the STA is using! Be sure to set 'channel=...' in the above file to a proper channel number.
Note: Refer to the kernel's hostapd documentation for more wireless configuration options.


In order for the concurrent modes to work, a separate virtual wireless device must first be created. Note that hostapd.conf above lists interface=p2p0, a second interface with this name must be created:

iw wlan0 interface add p2p0 type managed

The access point can then be started and tested by hand:

hostapd /etc/hostapd/hostapd.conf &

An IP address can be set to p2p0:

ifconfig p2p0 192.168.0.1

From this point, other Wi-Fi clients can connect to the SSID YourWiFiName with the WPA2 key Somepassphrase with a static IP in the range of 192.168.0.0/24, and will be able to access the platform at 192.168.0.1. More advanced configurations are also possible, including bridging, routing/NAT, or simply separate networks with the Wi-Fi module connecting to a network and hosting its own private network with DHCP.

Debian 10 - Installing New Software

Debian provides the apt-get system which allows management of pre-built applications. The apt tools require a network connection to the internet in order to automatically download and install new software. The update command will download a list of the current versions of pre-built packages.

apt-get update

A common example is installing Java runtime support for a system. Find the package name first with search, and then install it.

root@tsa38x:~# apt-cache search openjdk
default-jdk - Standard Java or Java compatible Development Kit
default-jdk-doc - Standard Java or Java compatible Development Kit (documentation)
default-jdk-headless - Standard Java or Java compatible Development Kit (headless)
default-jre - Standard Java or Java compatible Runtime
default-jre-headless - Standard Java or Java compatible Runtime (headless)
jtreg - Regression Test Harness for the OpenJDK platform
libreoffice - office productivity suite (metapackage)
openjdk-11-dbg - Java runtime based on OpenJDK (debugging symbols)
openjdk-11-demo - Java runtime based on OpenJDK (demos and examples)
openjdk-11-doc - OpenJDK Development Kit (JDK) documentation
openjdk-11-jdk - OpenJDK Development Kit (JDK)
openjdk-11-jdk-headless - OpenJDK Development Kit (JDK) (headless)
openjdk-11-jre - OpenJDK Java runtime, using Hotspot JIT
openjdk-11-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
openjdk-11-jre-zero - Alternative JVM for OpenJDK, using Zero
openjdk-11-source - OpenJDK Development Kit (JDK) source files
uwsgi-app-integration-plugins - plugins for integration of uWSGI and application
uwsgi-plugin-jvm-openjdk-11 - Java plugin for uWSGI (OpenJDK 11)
uwsgi-plugin-jwsgi-openjdk-11 - JWSGI plugin for uWSGI (OpenJDK 11)
uwsgi-plugin-ring-openjdk-11 - Closure/Ring plugin for uWSGI (OpenJDK 11)
uwsgi-plugin-servlet-openjdk-11 - JWSGI plugin for uWSGI (OpenJDK 11)
java-package - Utility for creating Java Debian packages

In this case, the wanted package will likely be the "openjdk-11-jre" package. Names of packages can be found on Debian's wiki pages or the packages site.

With the package name apt-get install can be used to install the prebuilt packages.

apt-get install openjdk-11-jre
# More than one package can be installed at a time.
apt-get install openjdk-11-jre nano vim mplayer

For more information on using apt-get refer to Debian's documentation here.

Debian 10 - Setting Up SSH

Openssh is installed in our default Debian image, but by default openssh does not permit root logins, and requires a password to be set. Additionally, a host key is required if one hasn't already been created on the target board. To allow remote root login:

sed --in-place 's/#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config
systemctl restart ssh.service
/bin/ls /etc/ssh/ssh_host*key >/dev/null 2>&1  || ssh-keygen -A
passwd root # Set any password

If you ssh to this system it will now support ssh as root.

Debian 10 - Starting Automatically

A systemd service can be created to start up headless applications. Create a file in /etc/systemd/system/yourapp.service

[Unit]
Description=Run an application on startup

[Service]
Type=simple
ExecStart=/usr/local/bin/your_app_or_script

[Install]
WantedBy=multi-user.target

If networking is a dependency add "After=network.target" in the Unit section. Once you have this file in place add it to startup with:

# Start the app on startup, but will not start it now
systemctl enable yourapp.service

# Start the app now, but doesn't change auto startup
systemctl start yourapp.service
Note: See the systemd documentation for in depth documentation on services.

Backup / Restore

MicroSD Card

These instructions describe how to create a bootable SD card image. They assume you have an SD card with one partition. Most SD cards ship this way by default, but if you have modified the partitions, you may need to use a utility such as gparted or fdisk to recreate the table with one partition.

These instructions assume your SD interface is /dev/sdc, but plug the SD card into your USB reader and check dmesg to confirm. On the TS-7180, its on-board SD card reader is /dev/mmcblk1p1.

Running these commands will reflash the SD card to our default latest image.

# Verify nothing else has this mounted
sudo umount /dev/sdc1

sudo mkfs.ext4 -O ^metadata_csum,^64bit /dev/sdc1
sudo mkdir /mnt/sd
sudo mount /dev/sdc1 /mnt/sd/
wget https://ftp.embeddedTS.com/ts-arm-sbc/ts-7180-linux/distributions/debian/ts7180-debian-buster-latest.tar.xz
xzcat ts7180-debian-buster-latest.tar.xz | sudo tar -xhf -C /mnt/sd
sudo umount /mnt/sd
sync

After it is written you can verify the data was written correctly. Reinsert the disk to verify any block cache is gone, then run these:

mount /dev/sdc1 /mnt/sd
cd /mnt/sd/
sudo md5sum -c md5sums.txt
umount /mnt/sd
sync

The md5sums command will report what differences there are, if any, and return if it passed or failed.

eMMC

The simplest way to backup/restore the eMMC is by booting to the SD card and then writing the eMMC image to removable media such as a USB stick.

sudo mkdir /mnt/emmc/
sudo mount /dev/mmcblk1p1 /mnt/emmc/
cd /mnt/emmc/
tar -c . | bzip2 > /path/to/ts7180-backup-image.tar.bz2
cd ../
umount /mnt/emmc/
sync

To write a new filesystem to the TS-7180, first boot to an SD card or USB stick. Then re-image the eMMC:

# The eMMC is /dev/mmcblk1.
#
# Ensure the media has an MBR (not GPT) partition table with exactly one partition.
# Re-partition the device with fdisk or gparted if it isn't already partitioned correctly.

sudo mkdir /mnt/emmc/

sudo mkfs.ext4 -O ^metadata_csum,^64bit /dev/mmcblk1p1
# If the above command fails, complaining of an invalid filesystem option, it is fine to omit that flag:
# An older mkfs.ext4 that doesn’t understand it also can’t create a backwards compatibility issue.

sudo mount /dev/mmcblk1p1 /mnt/emmc/
bzcat /path/to/ts7180-new-image.tar.bz2 | tar -xhf -C /mnt/emmc
umount /mnt/emmc/
sync

Linux Kernel (4.9/LTS)

This platform uses a 4.9 LTS kernel, the source for which is on github in our public github. Compiling the kernel requires an armhf toolchain.

Preparing to Build

We recommend building in a Debian environment, whether actual system (or VM) or a Docker container. Here are the instructions for each:

Building under Debian

Builds require several tools to be present your distribution. For Debian:

WARNING: This process may be broken for generic Debian; the commands for Ubuntu should be correct.
su root

apt-get install curl git build-essential lzop u-boot-tools libncursesw5-dev
echo "deb http://emdebian.org/tools/debian buster main" > /etc/apt/sources.list.d/emdebian.list
curl http://emdebian.org/tools/debian/emdebian-toolchain-archive.key | apt-key add -
dpkg --add-architecture armhf
apt-get update
apt-get install crossbuild-essential-armhf

For Ubuntu:

sudo apt-get update
sudo apt-get install crossbuild-essential-armhf git build-essential lzop u-boot-tools libncursesw5-dev

Building under Docker

Debian only provides their cross compiler for their distribution. Our examples will set up a Docker for Debian to use for development. If using Debian 10 Buster directly, or through a VM then the docker usage can be skipped.

Create a file called "Dockerfile" with these contents:

FROM debian:buster

RUN dpkg --add-architecture armhf

RUN apt-get update && apt-get install -y \
    autogen \
    automake \
    bash \
    bc \
    bison \
    build-essential \
    bzip2 \
    ca-certificates \
    ccache \
    chrpath \
    cpio \
    curl \
    diffstat \
    fakeroot \
    file \
    flex \
    gawk \
    gcc-arm-linux-gnueabihf \
    git \
    gzip \
    kmod \
    libgpiod-dev:armhf \
    libncursesw5-dev \
    libssl-dev \
    libtool \
    locales \
    lzop \
    make \
    multistrap \
    ncurses-dev \
    pkg-config \
    python \
    python3 \
    python3-pip \
    python3-pexpect \
    qemu-user-static \
    rsync \
    socat \
    runit \
    texinfo \
    u-boot-tools \
    unzip \
    vim \
    wget \
    xz-utils

# To make a more readable PS1 to show we are in the Docker
ENV debian_chroot debian_buster
RUN echo "PS1='\${debian_chroot}\\[\033[01;32m\\]@\\H\[\\033[00m\\]:\\[\\033[01;34m\\]\\w\\[\\033[00m\\]\\$ '" >> /etc/bash.bashrc

# Set up locales.  Needed by yocto.
RUN sed -i -e 's/# en_US.UTF-8 UTF-8/en_US.UTF-8 UTF-8/' /etc/locale.gen && \
        echo 'LANG="en_US.UTF-8"'>/etc/default/locale && \
        dpkg-reconfigure --frontend=noninteractive locales && \
        update-locale LANG=en_US.UTF-8

ENV LC_ALL en_US.UTF-8
ENV LANG en_US.UTF-8
ENV LANGUAGE en_US.UTF-8

In the same directory as the file named "Dockerfile" run:

docker build --tag armhf-buster-toolchain .

When this has finished the docker can be used with:

docker run --rm -it --volume $(pwd):/work armhf-buster-toolchain bash

This will map the current directory to /work.

At this point the Debian Docker is ready to compile armhf binaries. For example, create a hello world in your home folder at ~/hello.c

#include <stdio.h>
int main(){
    printf("Hello World\n");
}

To compile this enter the docker with:

docker run -it --volume $(pwd):/work armhf-buster-toolchain bash
# Then from the docker:
cd /work/
arm-linux-gnueabihf-gcc hello.c -o hello

Check "file hello" to verify the binary type:

user@host:~/$ file hello
hello: ELF 32-bit LSB pie executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 3.2.0, BuildID[sha1]=8a8cee3341d3ef76ef6796f72d5722ae9d77c8ea, not stripped

This can also be used to develop against dynamic libraries from Debian. The armhf packages can be installed in the Docker. For example, to link against curl:

# Enter the Docker:
docker run -it --volume $(pwd):/work armhf-buster-toolchain bash
cd /work/

apt-get install libcurl4-openssl-dev:armhf
# Download curl's simple.c example
wget https://raw.githubusercontent.com/bagder/curl/master/docs/examples/simple.c
arm-linux-gnueabihf-gcc simple.c -o simple -lcurl

The "simple" binary is now built for armhf and links dynamically to curl.

This will only retain the armhf libcurl package until the docker is exited. To make the changes permanent, add the package to the Dockerfile and rerun:

docker build --tag armhf-buster-toolchain .

Compiling the Kernel

Once your build environment is prepared:

git clone https://github.com/embeddedTS/linux-lts
# To do a shallow clone of just the latest snapshot of the linux-4.9.y branch, which results in a smaller download size and size on disk, the following command can be used:
# git clone --depth 1 https://github.com/embeddedTS/linux-lts -b linux-4.9.y
cd linux-lts
git checkout linux-4.9.y

## If you are using the 64-bit toolchain:
export CROSS_COMPILE=arm-linux-gnueabihf-
export ARCH=arm
export LOADADDR=0x80800000

make tsimx6ul_defconfig

## Make any changes in "make menuconfig" or driver modifications, then compile
make && make zImage && make modules

Installing the Kernel, Headers, or Modules

To install the headers and/or objects built above to a board, first create a tarball so you can copy it to removable media or another machine.

The following will install the kernel and modules to a temporary directory, and then pack them up in to a single tarball:

TEMPDIR=$(mktemp -d)
mkdir "${TEMPDIR}/boot/"
cp arch/arm/boot/zImage "${TEMPDIR}"/boot/zImage
cp arch/arm/boot/dts/imx6ul*ts*.dtb  "${TEMPDIR}"/boot/
INSTALL_MOD_PATH="${TEMPDIR}" make modules_install
INSTALL_HDR_PATH="${TEMPDIR}" make headers_install 
tar czf linux-tsimx6ul-"$(cat include/config/kernel.release)"-"$(date +"%Y%m%d")".tar.gz -C "${TEMPDIR}" .
rm -rf "${TEMPDIR}"

This will output a tarball with the kernel version and short git hash, as well as the date the tarball was created. For example: linux-tsimx6ul-v4.9.171-60-g01e2117e-20190823.tar.gz

This tarball can be directly unpacked to the root folder of a bootable media for the device. It is also possible to unpack it directly on a booted system, however we do not recommend doing so on an active deployed system without extensive testing.

# Unpack it to a mounted disk, this assumes the disk is mounted to "/mnt"
zcat linux-tsimx6ul...tar.gz | tar xh -C /mnt

# Unpack it to the root directory of a booted system
zcat linux-tsimx6ul...tar.gz | tar xh -C /

Troubleshooting

If you experience problems compiling the kernel with the compiler in your distribution, please try whichever of the below toolchains is appropriate for your architecture:

In the case of either toolchain you would run these commands to install them:

chmod a+x poky-*.sh
sudo ./poky-*.sh

Features

ADC

The TS-7180 has four ADC channels, whose inputs are available on the P3 connector as AN_IN_1 through AN_IN_4. Each input may be configured to measure voltage in either one of two ranges (0-2.5V and 0-10.9V) or a 20mA current-loop. Voltage measurements outside those ranges can be accomplished by adding an external voltage divider and then also making corresponding adjustments to the scaling applied in the code examples below.

These ADCs are accessed through the IIO layer in Linux. This provides ADC samples up to 6ksps between all channels. The simplest API for slow speed acquisition is through /sys/:

cat /sys/bus/iio/devices/iio\:device0/in_voltage4_raw

To switch to the 10.9V input range, the appropriate enable must be set high. Each input AN_IN_1 through AN_IN_4 has its own enable, EN_ADC1_10V through EN_ADC4_10V, and these are controlled by GPIO #10 through #13. For example, to switch AN_IN_1 to the 10.9V range, run the following command:

gpioset 5 10=1

Note that the result must now be multiplied by (10.9/2.5). Note also that the input impedance will now be around 2k ohms.

To switch to the 20mA current-loop mode, the appropriate enable must be set high. These are EN_CL_1 through EN_CL_4, and are controlled by GPIO #6 through #9.

# Select 2.5V
gpioset 5 10=0
# Asssert EN_CL_1
gpioset 5 6=1
ADC Table
# 'raw' 2.5/10.9V Select 20mA Loop Select
AN_IN_1 in_voltage4_raw gpio bank 5 io 10 gpio bank 5 io 6
AN_IN_2 in_voltage5_raw gpio bank 5 io 11 gpio bank 5 io 7
AN_IN_3 in_voltage8_raw gpio bank 5 io 12 gpio bank 5 io 8
AN_IN_4 in_voltage9_raw gpio bank 5 io 13 gpio bank 5 io 9
Note: The four ADC inputs use the CPU ADC inputs 4,5,8, and 9, corresponding with the 'raw' entries in the above table.

The libiio library provides simple access to the IO. The fastest API is in C which will get about 6ksps.

/* Build with gcc adc-test.c -o adc-test -liio 
 * Gets ~6ksps
 * At the time of writing this does not support the buffer interface */

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>
#include <errno.h>
#include <iio.h>

uint32_t scale_mv(uint32_t raw)
{
	/* scale a 0-4095 raw reading to 0-2500 mV */
	uint32_t val = raw * 5000 / (4095 * 2);

	return val;
}

int main(int argc, char **argv)
{
	static struct iio_context *ctx;
	static struct iio_device *dev;
	static struct iio_channel *chn[4];
	int i, ret;
	long long sample;

	ctx = iio_create_default_context();
	assert(ctx);
	dev = iio_context_find_device(ctx, "2198000.adc");
	assert(dev);

	chn[0] = iio_device_find_channel(dev, "voltage4", false);
	chn[1] = iio_device_find_channel(dev, "voltage5", false);
	chn[2] = iio_device_find_channel(dev, "voltage8", false);
	chn[3] = iio_device_find_channel(dev, "voltage9", false);

	for (i = 0; i < 4; i++) {
		ret = iio_channel_attr_read_longlong(chn[i], "raw", &sample);
		assert(!ret);
		printf("AN_CH%d_mv=%d\n", i, scale_mv((uint32_t)sample));
	}

	return 0;
}

The python bindings currently achieve about 2ksps with similar code.

#!/usr/bin/env python

import iio

ctx = iio.Context('local:')
dev = ctx.find_device('2198000.adc')

scan_channels = ["voltage4", "voltage5", "voltage8", "voltage9"]

for n, chan_name in enumerate(scan_channels, start=1):
	chn = dev.find_channel(chan_name)
	raw = int(chn.attrs['raw'].value)

	# Scale 0-4095 raw value to 0-2500(mV)
	scaled = raw * (2.5/4095)

	print('AN_CH{}_V={:.3f}'.format(n, scaled))

Bluetooth

The Wi-Fi option for this platform also includes a Bluetooth 5.0 LE module. Support for Bluetooth is provided by the BlueZ project. BlueZ has support for many different profiles for HID, A2DP, and many more. Refer to the BlueZ documentation for more information. Please see our BLE Examples page for information on installing the latest BlueZ release, getting started, and using demo applications.

Both Wi-Fi and Bluetooth can be active at the same time on this platform. Note however, that either the Wi-Fi interface needs to be not brought up if Wi-Fi is unused, or it needs to actively connect to an access point or act as an access point. The Bluetooth module can be activated with the following commands:

For Bluez versions found on Debian Stretch and below:

# Enable Bluetooth, and load the firmware
echo BT_POWER_UP > /dev/wilc_bt
sleep 1
echo BT_DOWNLOAD_FW > /dev/wilc_bt
sleep 1

# Attach the BLE device to the system, increase the baud, and enable flow control
hciattach /dev/ttymxc2 any 115200 noflow
sleep 1
hcitool cmd 0x3F 0x0053 00 10 0E 00 01
stty -F /dev/ttymxc2 921600 crtscts

# Note that no other HCI commands should be used! In older versions of BlueZ, HCI commands exist alongside bluetoothd, however HCI commands can interfere with the bluetoothd stack.


For newer versions of BlueZ found on Debian Buster or newer, or newer versions of BlueZ built from source:

echo BT_POWER_UP > /dev/wilc_bt
sleep 1
echo BT_DOWNLOAD_FW > /dev/wilc_bt
sleep 1

btattach -N -B /dev/ttymxc2 -S 115200 &
sleep 1
bluetoothctl power on
sleep 1
hcitool cmd 0x3F 0x0053 00 10 0E 00 01
kill %1 # This terminates the above btattach command
sleep 1
btattach -B /dev/ttymxc2 -S 921600 &


At this point, the device is running at 921600 baud with flow control, and is fully set up ready to be controlled by various components of BlueZ tools. For example, to do a scan of nearby devices:

bluetoothctl
power on
scan on

This will return a list of devices such as:

root@ts-imx6ul:~# bluetoothctl  
Agent registered
[CHG] Controller F8:F0:05:XX:XX:XX Pairable: yes
[bluetooth]# power on
Changing power on succeeded
[CHG] Controller F8:F0:05:XX:XX:XX Powered: yes
[bluetooth]# scan on
Discovery started
[CHG] Controller F8:F0:05:XX:XX:XX Discovering: yes
[NEW] Device 51:DD:C0:XX:XX:XX Device_Name
[NEW] Device 2A:20:E2:XX:XX:XX Device_Name
[CHG] Device 51:DD:C0:XX:XX:XX RSSI: -93
[CHG] Device 51:DD:C0:XX:XX:XX RSSI: -82
[NEW] Device E2:08:B5:XX:XX:XX Device_Name
[CHG] Device 51:DD:C0:XX:XX:XX RSSI: -93
[CHG] Device 2A:20:E2:XX:XX:XX RSSI: -94
[NEW] Device 68:62:92:XX:XX:XX Device_Name
[NEW] Device 68:79:12:XX:XX:XX Device_Name
[bluetooth]# quit

Please note that the Bluetooth module requires the modem control lines CTS and RTS as flow control when running at higher baud rates. It is possible to run the module at the initial 115200 baud if the flow control lines are unwanted.

The module supports some other commands as well:

# Allow the BT chip to enter sleep mode
echo BT_FW_CHIP_ALLOW_SLEEP > /dev/wilc_bt

# Power down the BT radio when not in use
echo BT_POWER_DOWN > /dev/wilc_bt

CAN

The i.MX6UL includes 2 CAN controllers which support the SocketCAN interface, and these are presented on the P3 & P5 connectors (custom populations may differ).

Before proceeding with the examples, see the Kernel's CAN documentation here.

Note: The EN_CAN_XVR# line must be set low, by executing the following command: tshwctl -a 20 -w 1

This board comes preinstalled with can-utils which can be used to communicate over a CAN network without writing any code. The candump utility can be used to dump all data on the network

## First, set the baud rate and bring up the device:
ip link set can0 type can bitrate 250000
ip link set can0 up

## Dump data & errors:
candump can0 &

## Send the packet with:
#can_id = 0x7df
#data 0 = 0x3
#data 1 = 0x1
#data 2 = 0x0c
cansend can0 -i 0x7DF 0x3 0x1 0x0C
## Some versions of cansend use a different syntax.  If the above
## commands gives an error, try this instead:
#cansend can0 7DF#03010C

The above example packet is designed to work with the Ozen Elektronik myOByDic 1610 ECU simulator to read the RPM speed. In this case, the ECU simulator would return data from candump with:

 <0x7e8> [8] 04 41 0c 60 40 00 00 00 
 <0x7e9> [8] 04 41 0c 60 40 00 00 00 

In the output above, columns 6 and 7 are the current RPM value. This shows a simple way to prove out the communication before moving to another language.

The following example sends the same packet and parses the same response in C:

#include <stdio.h>
#include <pthread.h>
#include <net/if.h>
#include <string.h>
#include <unistd.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <assert.h>
#include <linux/can.h>
#include <linux/can/raw.h>

int main(void)
{
	int s;
	int nbytes;
	struct sockaddr_can addr;
	struct can_frame frame;
	struct ifreq ifr;
	struct iovec iov;
	struct msghdr msg;
	char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) + CMSG_SPACE(sizeof(__u32))];
	char *ifname = "can0";
 
	if((s = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0) {
		perror("Error while opening socket");
		return -1;
	}
 
	strcpy(ifr.ifr_name, ifname);
	ioctl(s, SIOCGIFINDEX, &ifr);
	addr.can_family  = AF_CAN;
	addr.can_ifindex = ifr.ifr_ifindex;
 
	if(bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
		perror("socket");
		return -2;
	}
 
 	/* For the ozen myOByDic 1610 this requests the RPM guage */
	frame.can_id  = 0x7df;
	frame.can_dlc = 3;
	frame.data[0] = 3;
	frame.data[1] = 1;
	frame.data[2] = 0x0c;
 
	nbytes = write(s, &frame, sizeof(struct can_frame));
	if(nbytes < 0) {
		perror("write");
		return -3;
	}

	iov.iov_base = &frame;
	msg.msg_name = &addr;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_control = &ctrlmsg;
	iov.iov_len = sizeof(frame);
	msg.msg_namelen = sizeof(struct sockaddr_can);
	msg.msg_controllen = sizeof(ctrlmsg);  
	msg.msg_flags = 0;

	do {
		nbytes = recvmsg(s, &msg, 0);
		if (nbytes < 0) {
			perror("read");
			return -4;
		}

		if (nbytes < (int)sizeof(struct can_frame)) {
			fprintf(stderr, "read: incomplete CAN frame\n");
		}
	} while(nbytes == 0);

	if(frame.data[0] == 0x4)
		printf("RPM at %d of 255\n", frame.data[3]);
 
	return 0;
}

See the Kernel's CAN documentation here. Other languages have bindings to access CAN such as Python, Java using JNI.

In production use of CAN we also recommend setting a restart-ms for each active CAN port.

ip link set can0 type can restart-ms 100

This allows the CAN bus to automatically recover in the event of a bus-off condition.

COM Ports (see Serial Ports, below )

CPU

The TS-7180 uses a 696MHz NXP i.MX6UL applications processor, which is very similar to the i.MX6 Solo used on the TS-4900. The 6UL has many of the same peripheral IP cores, but it omits the GPU and replaces the ARM Cortex-A9 with a Cortex-A7 CPU to target lower power consumption. Refer to NXP's documentation for more detailed information on the CPU core:

CPU Frequency Scaling

The i.MX6UL CPU has a number of power management features to scale the CPU speed. The maximum speed of the i.MX6UL is 696 MHz; other frequencies possible are 528 MHz, 396 MHz, and 198 MHz. By default, the "ondemand" frequency governor is used. This allows the CPU to run at its lowest speed and increase it when there is computation demand. Other governors are available, see the kernel documentation for a list of these governors and their operation.

The current CPU frequency as well as the governor used are modified by a set of files within the folder "/sys/bus/cpu/devices/cpu0/cpufreq". Some key files are outlined below:

 /sys/bus/cpu/devices/cpu0/cpufreq/cpuinfo_cur_freq - Lists the current frequency
 /sys/bus/cpu/devices/cpu0/cpufreq/scaling_governor - Lists/sets the current frequency governor
 /sys/bus/cpu/devices/cpu0/cpufreq/scaling_setspeed - When govenor is "userspace", set current frequency
 /sys/bus/cpu/devices/cpu0/cpufreq/scaling_available_frequencies - List all available frequencies
 /sys/bus/cpu/devices/cpu0/cpufreq/scaling_available_governors - List all available governors

In order to manually specify a frequency, the frequency governor must be set to userspace. For example, to force the lowest CPU frequency all the time:

echo "userspace" > /sys/bus/cpu/devices/cpu0/cpufreq/scaling_governor
echo "198000" > /sys/bus/cpu/devices/cpu0/cpufreq/scaling_setspeed

Temperature Monitoring

The i.MX6UL CPU has an internal TEMPMON peripheral that is supported by Linux's Thermal Zone management. This on-die sensor is meant to measure of the thermal state of the CPU for throttling control. This can be read via the Linux kernel's sysfs (/sys) interface. The following command returns the temperature in millicelsius:

cat /sys/class/thermal/thermal_zone0/temp

eMMC

This board includes a Micron eMMC module. Our off-the-shelf builds are 4GiB, but up to 64GiB are available for larger builds. The eMMC flash appears to Linux as an SD card at /dev/mmcblk1. Our default programming will include one partition programmed with our Debian image.

eMMC also provides ways to estimate the wear on the module. First, determine your eMMC chipset revision:

root@tsimx6:~# mmc extcsd read /dev/mmcblk1 | grep "CSD rev"
[64446.059203]  mmcblk1: p1
  Extended CSD rev 1.7 (MMC 5.0)

or

root@tsimx6:~# mmc extcsd read /dev/mmcblk1 | grep "CSD rev"
[64446.059203]  mmcblk1: p1
  Extended CSD rev 1.5 (MMC 4.41)

In eMMC revision 5.0 and above, part of the specification includes a way to estimate lifetime of the chipset. For example:

root@tsimx6:~# mmc extcsd read /dev/mmcblk1 | grep -e EXT_CSD_DEVICE_LIFE_TIME -e PRE_EOL
[64618.159298]  mmcblk1: p1
eMMC Life Time Estimation A [EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_A]: 0x01
eMMC Life Time Estimation B [EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_B]: 0x01
eMMC Pre EOL information [EXT_CSD_PRE_EOL_INFO]: 0x01

If you have reconfigured your device as SLC, use TYP_A. If you are using the default MLC setting, use TYP_B. These LIFE_TIME_EST values indicate in 10s of percent how much of the reserve blocks are still available. The 0x1 value indicates < 10%. 0x7 would indicate < 70%.

EXT_CSD_PRE_EOL_INFO can also be used as an early warning indicator.

EXT_CSD_PRE_EOL_INFO values
Value Description
0x1 Normal (< 80% blocks used)
0x2 Warning (> 80% blocks used)
0x3 Urgent (>90% blocks used)

If this is below 5.0, you must use a vendor specific utility. Micron eMMC uses the emmcparm utility. Refer to Micron's TN-FC-25 for the emmcparm utility and related documentation.


Ethernet Ports

The NXP iMX6.UL processor implements two 10/100 Ethernet controllers via external Microchip/Micrel KSZ8081 PHYs and dual RJ45 jacks at the edge of the board. Their MAC addresses will always be sequential and are assigned from a Technologic Systems pool (e8:1a:58 or 00:d0:69).

Support is built into U-Boot as well as the Linux kernel, where standard utilities such as ifconfig/ip can be used to control these interfaces. See the Configuring the Network section for more details. The Precision Time Protocol (PTP) is also supported. For further specifics of this controller, see the CPU manual.

When the optional TS-DC767-POE daughter-card is installed, Power-over-Ethernet (PoE) may be received only via eth1 (ethernet@2188000 in U-Boot), which is the second port in the picture above.

Precision Time Protocol (PTP)

The i.MX6UL CPU Ethernet supports 1588 PTP (PTPv1 & PTPv2).

PTP is supported in Linux via the linuxptp project. This allows synchronizing the system clock to within ±1 us.

Note that Linux kernel version 4.9 or greater is required for PTP support with the i.MX6UL CPU. An example of setting up an ethernet interface with PTP and adjusting the clock based on that is below.

apt-get install linuxptp -y

# For PTP on eth0
phc2sys -s /dev/ptp0 -w &
ptp4l -2 -H -i eth0 -m -p /dev/ptp0 &

# For PTP on eth1
phc2sys -s /dev/ptp1 -w &
ptp4l -2 -H -i eth1 -m -p /dev/ptp1 &

If the clocks are significantly off this may take time for the clocks to converge.

FPGA

FPGA Registers

The recommended way to access the TS-7180 FPGA's forty-four GPIO registers is with Linux's gpioset and gpioget commands (see: GPIO).

The supplied tshwctl utility may also be used to access these registers; run tshwctl -h to see how to use it.

Internally, the TS-7180 accesses its FPGA registers over the 6UL's I2C bus 3. You should only need to do this in programming environments that lack both of those methods mentioned above. The FPGA is available at I2C addresses 0x28-0x2f. First write the address (which is two bytes wide), followed by the data, which is one byte.

The tables below lists all FPGA registers and their functions.

FPGA Registers
Address Bits Description
0-43[2] 7:3 Reserved (Write 0)
2 GPIOn Input Data
1 GPIOn Output Data
0 GPIOn Output Enable
307 7:3 Reserved (Write 0)
2:0 XBee/Nimbelink/MultiTech Cell-modem UART selector (default: 0)
Value Function
0 Leave disconnected
1 Steal UART3 (ttymxc2) from BT
2 Steal UART4 (ttymxc3) from RS-485
3 Steal UART6 (ttymxc5) from RS-232 (on P5 pins 10/11)
4 Steal UART7 (ttymxc6) from RS-232 (on P5 pins 7/8)
5 Steal UART8 (ttymxc7) from GPS
308 7:3 Reserved (Write 0)
2:0 HD12 UART selector (default: 0)
Value Function
0 Leave disconnected
1 Steal UART3 (ttymxc2) from BT
2 Steal UART4 (ttymxc3) from RS-485
3 Steal UART6 (ttymxc5) from RS-232 (on P5 pins 10/11)
4 Steal UART7 (ttymxc6) from RS-232 (on P5 pins 7/8)
5 Steal UART8 (ttymxc7) from GPS
309 0 PWM control[3]
310 7:0 GPIO chip 0/pin 18 (SPARE_1) MUX[4]
(1 = connected, 0 = ignored)
Bit Enable
0 DIG_IN_1
1 DIG_IN_2
2 DIG_IN_3
3 DIG_IN_4
4 DIO_1_IN
5 DIO_2_IN
6 DIO_3_IN
7 DIO_4_IN
311 7:0 Polarity into GPIO chip 0/pin 18 (SPARE_1) MUX[4]
Bit Active High EN
0 DIG_IN_1
1 DIG_IN_2
2 DIG_IN_3
3 DIG_IN_4
4 DIO_1_IN
5 DIO_2_IN
6 DIO_3_IN
7 DIO_4_IN
  1. We format our eMMC and other media with GPT.
  2. Each address value corresponds to one GPIO number (n) in the table below.
  3. Write 1 to this address to route the CPU PWM to DIO_1
  4. 4.0 4.1 Requires a board with FPGA version 16 or later.


FPGA GPIOs

The FPGA's GPIOs are "gpiochip5" in the Linux GPIO subsystem.

FPGA GPIO
IO Number Pad Direction
0 WIFI_RESET# OUT
1 EN_WIFI_PWR OUT
2 EN_YEL_LED# OUT
3 EN_GREEN_LED# OUT
4 EN_RED_LED# OUT
5 EN_BLUE_LED# OUT
6 EN_CL_1 OUT
7 EN_CL_2 OUT
8 EN_CL_3 OUT
9 EN_CL_4 OUT
10 EN_ADC1_10V OUT
11 EN_ADC2_10V OUT
12 EN_ADC3_10V OUT
13 EN_ADC4_10V OUT
14 EN_SD_POWER OUT
15 EN_USB_HOST_5V OUT
16 EN_OFF_BD_5V OUT
17 EN_CELL_MODEM_PWR OUT
18 EN_NIMBEL_3.3V OUT
19 EN_GPS_PWR# OUT
20 EN_CAN_XVR# OUT
21 EN_232_XVR OUT
22 EN_LS_OUT_1 OUT
23 EN_LS_OUT_2 OUT
24 EN_LS_OUT_3 OUT
25 EN_LS_OUT_4 OUT
26 EN_LS_OUT_5 OUT
27 EN_LS_OUT_6 OUT
28 EN_LS_OUT_7 OUT
29 MT_RESET# [1] OUT
30 Unused n/a
31 Unused n/a
32 DIG_IN_1 IN
33 DIG_IN_2 IN
34 DIG_IN_3 IN
35 DIG_IN_4 IN
36 SD_BOOT_JMP# IN
37 DIO_IN_1 IN
38 DIO_IN_2 IN
39 DIO_IN_3 IN
40 DIO_IN_4 IN
41 DIO_IN_5 IN
42 DIO_IN_6 IN
43 DIO_IN_7 IN
  1. Requires a board with FPGA version 16 or later.

FRAM

This platform supports a soldered-down, non-volatile Ferroelectric RAM (FRAM) device. The Cypress FM25L16B is a 2 KiB FRAM device in a configuration not unlike an SPI EEPROM. The nature of FRAM means it is non-volatile, incredibly fast to write, and is specified with 100 trillion read/write cycles (per each of the 256 sequential 8 byte rows) with a 150 year data retention at temperatures below 65 °C. The device is connected to Linux and presents itself as a flat file that can be read and written like any standard Linux file.


The FRAM can be accessed as a flat file from Linux:

# xxd -a /sys/class/spi_master/spi2/spi2.2/eeprom | head
00000000: 0000 0000 0000 0000 0000 0000 0000 0000  ................
*
000007f0: 0000 0000 0000 0000 0000 0000 0000 0030  ...............0

If U-Boot's bootcount tracking environment variable is enabled, the last byte of FRAM is reserved for storing the boot count, and care should be taken to not overwrite it inadvertently. In U-Boot, the boot count can be accessed with the fram command.

GPIO

The i.MX6UL CPU and FPGA GPIO are exposed using a kernel character device. This interface provides a set of files and directories for interacting with GPIO which can be used from any language that interact with special files in linux using ioctl() or similar. For our platforms, we pre-install the "libgpiod" library and binaries package. Documentation on this package can be found here. This section only covers using these userspace tools and does not provide guidance on using the libgpiod library in end applications. Please see the libgpiod documentation for this purpose.

A user with suitable permissions to read and write /dev/gpiochip* files can immediately interact with GPIO pins. For example, to read the push_sw:

gpioget 2 18 # Returns 0 when pressed, 1 when not

Multiple pins in the same chip can be read simultaneously by passing multiple pin numbers separated by spaces.

This GPIO interface also provides labels for all the I/O. To get a reference from the board of all GPIO run:

gpioinfo

The TS-7180 provides seven IO ports that can sink up to 500mA, or withstand up to 30V at the input. These are available on the P3 connector. DIO_1 through DIO_7 appear as GPIO bank 5 io 37 through 43 (when used as inputs), and as GPIO bank 5 io 22 through 28 (when used as outputs). For example, to read the state of DIO_1, enter the following command:

gpioget 5 37

To drive enable the 500mA sink, enter the following command:

gpioset 5 22=1
gpiochip0 - 32 lines:
	line   0: "BOOT_MODE_0" unused input active-high 
	line   1:      unnamed       unused   input  active-high 
	line   2:  "I2C_1_CLK"       unused   input  active-high 
	line   3:  "I2C_1_DAT"       unused   input  active-high 
	line   4:      "ADC_1"       unused   input  active-high 
	line   5:      "ADC_2"       unused   input  active-high 
	line   6:   "ETH_MDIO"       unused   input  active-high 
	line   7:    "ETH_MDC"       unused   input  active-high 
	line   8:      "ADC_3"       unused   input  active-high 
	line   9:      "ADC_4"       unused   input  active-high 
	line  10:      unnamed       unused   input  active-high 
	line  11:      unnamed       unused   input  active-high 
	line  12:      unnamed       unused   input  active-high 
	line  13:      unnamed       unused   input  active-high 
	line  14:      unnamed       unused   input  active-high 
	line  15:      unnamed       unused   input  active-high 
	line  16: "CONSOLE_TXD" unused input active-high 
	line  17: "CONSOLE_RXD" unused input active-high 
	line  18:    "SPARE_1"       unused   input  active-high 
	line  19:     "EN_485"       unused   input  active-high 
	line  20:  "UART2_TXD"       unused   input  active-high 
	line  21:  "UART2_RXD"       unused   input  active-high 
	line  22:  "CAN_2_TXD"       unused   input  active-high 
	line  23: "CAN2_RXD_3V" unused input active-high 
	line  24:  "UART3_TXD"       unused   input  active-high 
	line  25:  "UART3_RXD"       unused   input  active-high 
	line  26: "UART3_CTS#"       unused   input  active-high 
	line  27: "UART3_RTS#"       unused   input  active-high 
	line  28:  "UART4_TXD"       unused   input  active-high 
	line  29:  "UART4_RXD"       unused   input  active-high 
	line  30:  "UART5_TXD"       unused   input  active-high 
	line  31:  "UART5_RXD"       unused   input  active-high 
gpiochip1 - 32 lines:
	line   0: "ENET1_RX_DATA0" unused input active-high 
	line   1: "ENET1_RX_DATA1" unused input active-high 
	line   2: "ENET1_RX_EN" unused input active-high 
	line   3: "ENET1_TX_DATA0" unused input active-high 
	line   4: "ENET1_TX_DATA1" unused input active-high 
	line   5: "ENET1_TX_EN" unused input active-high 
	line   6: "ENET1_TX_CLK" unused input active-high 
	line   7: "ENET1_RX_ER" unused input active-high 
	line   8: "ENET2_RX_DATA0" unused input active-high 
	line   9: "ENET2_RX_DATA1" unused input active-high 
	line  10: "ENET2_RX_EN" unused input active-high 
	line  11: "ENET2_TX_DATA0" unused input active-high 
	line  12: "ENET2_TX_DATA1" unused input active-high 
	line  13: "ENET2_TX_EN" unused input active-high 
	line  14: "ENET2_TX_CLK" unused input active-high 
	line  15: "ENET2_RX_ER" unused input active-high 
	line  16:     "SD_CMD"       unused   input  active-high 
	line  17:     "SD_CLK"       unused   input  active-high 
	line  18:      "SD_D0"       unused   input  active-high 
	line  19:      "SD_D1"       unused   input  active-high 
	line  20:      "SD_D2"       unused   input  active-high 
	line  21:      "SD_D3"       unused   input  active-high 
	line  22:      unnamed       unused   input  active-high 
	line  23:      unnamed       unused   input  active-high 
	line  24:      unnamed       unused   input  active-high 
	line  25:      unnamed       unused   input  active-high 
	line  26:      unnamed       unused   input  active-high 
	line  27:      unnamed       unused   input  active-high 
	line  28:      unnamed       unused   input  active-high 
	line  29:      unnamed       unused   input  active-high 
	line  30:      unnamed       unused   input  active-high 
	line  31:      unnamed       unused   input  active-high 
gpiochip2 - 32 lines:
	line   0: "HD1_SPI_CS"    "spi_imx"  output  active-high [used]
	line   1: "JTAG_FPGA_TCK" unused input active-high 
	line   2: "JTAG_FPGA_TMS" unused input active-high 
	line   3: "JTAG_FPGA_TDI" unused input active-high 
	line   4:      "WDOG#"       unused   input  active-high 
	line   5:  "I2C_3_DAT"       unused   input  active-high 
	line   6:  "I2C_3_CLK"       unused   input  active-high 
	line   7:      unnamed       unused   input  active-high 
	line   8: "HD1_I2C_CLK" "scl" output active-high [used]
	line   9: "HD1_I2C_DAT" "sda" output active-high [used]
	line  10: "HD1_DIG_INPUT" unused input active-high 
	line  11: "NO_CHRG_JMP#" unused input active-high 
	line  12: "EN_NIM_USB#" unused input active-high 
	line  13:  "CAN_1_TXD"       unused   input  active-high 
	line  14: "CAN1_RXD_3V" unused input active-high 
	line  15:  "XBEE_CTS#"       unused   input  active-high 
	line  16: "U_BOOT_JMP#" unused input active-high 
	line  17:      unnamed       unused   input  active-high 
	line  18: "PUSH_SW_CPU#" unused input active-high 
	line  19: "NIMBEL_PWR_ON" unused input active-high 
	line  20:      unnamed       unused   input  active-high 
	line  21:  "UART7_TXD"       unused   input  active-high 
	line  22:  "UART7_RXD"       unused   input  active-high 
	line  23:        "ID4"       unused   input  active-high 
	line  24: "JTAG_FPGA_TDO" unused input active-high 
	line  25:  "UART8_TXD"       unused   input  active-high 
	line  26:  "UART8_RXD"       unused   input  active-high 
	line  27:        "ID1"       unused   input  active-high 
	line  28: "ETH_PHY_RESET#" unused input active-high 
	line  29:      unnamed       unused   input  active-high 
	line  30:      unnamed       unused   input  active-high 
	line  31:      unnamed       unused   input  active-high 
gpiochip3 - 32 lines:
	line   0:   "EMMC_CLK"       unused   input  active-high 
	line   1:   "EMMC_CMD"       unused   input  active-high 
	line   2:    "EMMC_D0"       unused   input  active-high 
	line   3:    "EMMC_D1"       unused   input  active-high 
	line   4:    "EMMC_D2"       unused   input  active-high 
	line   5:    "EMMC_D3"       unused   input  active-high 
	line   6:  "SPI_4_CLK"       unused   input  active-high 
	line   7: "SPI_4_MOSI"       unused   input  active-high 
	line   8: "SPI_4_MISO"       unused   input  active-high 
	line   9:  "SPI_4_CS#"    "spi_imx"  output  active-high [used]
	line  10:  "MAG_N_IRQ"       unused   input  active-high 
	line  11: "FPGA_RESET#" unused input active-high 
	line  12: "SPI_3_FPGA_CS#" "spi_imx" output active-high [used]
	line  13:  "SPI_3_CLK"       unused   input  active-high 
	line  14: "SPI_3_MOSI"       unused   input  active-high 
	line  15: "SPI_3_MISO"       unused   input  active-high 
	line  16:      "PWM_5"       unused   input  active-high 
	line  17:  "UART6_TXD"       unused   input  active-high 
	line  18:  "UART6_RXD"       unused   input  active-high 
	line  19:        "ID5"       unused   input  active-high 
	line  20:   "GYRO_INT"       unused   input  active-high 
	line  21: "6UL_FORCE_5V_ON" unused input active-high 
	line  22: "EN_EMMC_3.3V#" "?" output active-low [used]
	line  23: "EN_YEL_LED#" "?" output active-low [used]
	line  24: "EN_RED_LED#" "?" output active-low [used]
	line  25: "EN_GRN_LED#" "?" output active-low [used]
	line  26: "EN_BLU_LED"          "?"  output  active-high [used]
	line  27: "FRAM_SPI_CS#" "spi_imx" output active-high [used]
	line  28: "SD_VSEL_1.8V" unused input active-high 
	line  29:      unnamed       unused   input  active-high 
	line  30:      unnamed       unused   input  active-high 
	line  31:      unnamed       unused   input  active-high 
gpiochip4 - 32 lines:
	line   0: "POWER_FAIL"       unused   input  active-high 
	line   1:   "FPGA_IRQ"       unused   input  active-high 
	line   2:      unnamed       unused   input  active-high 
	line   3:  "GPIO_DVFS"          "?"  output  active-high [used]
	line   4:      unnamed       unused   input  active-high 
	line   5: "SILAB_C2_CLK" unused input active-high 
	line   6: "SILAB_C2_DATA" unused input active-high 
	line   7: "SILAB_C2_RESET" unused input active-high 
	line   8:    "SPARE_4"       unused   input  active-high 
	line   9:      unnamed       unused   input  active-high 
	line  10:      unnamed       unused   input  active-high 
	line  11:      unnamed       unused   input  active-high 
	line  12:      unnamed       unused   input  active-high 
	line  13:      unnamed       unused   input  active-high 
	line  14:      unnamed       unused   input  active-high 
	line  15:      unnamed       unused   input  active-high 
	line  16:      unnamed       unused   input  active-high 
	line  17:      unnamed       unused   input  active-high 
	line  18:      unnamed       unused   input  active-high 
	line  19:      unnamed       unused   input  active-high 
	line  20:      unnamed       unused   input  active-high 
	line  21:      unnamed       unused   input  active-high 
	line  22:      unnamed       unused   input  active-high 
	line  23:      unnamed       unused   input  active-high 
	line  24:      unnamed       unused   input  active-high 
	line  25:      unnamed       unused   input  active-high 
	line  26:      unnamed       unused   input  active-high 
	line  27:      unnamed       unused   input  active-high 
	line  28:      unnamed       unused   input  active-high 
	line  29:      unnamed       unused   input  active-high 
	line  30:      unnamed       unused   input  active-high 
	line  31:      unnamed       unused   input  active-high 
gpiochip5 - 64 lines:
	line   0: "WIFI_RESET#" unused output active-high 
	line   1: "EN_WIFI_PWR" unused output active-high 
	line   2:      unnamed       unused   input  active-high 
	line   3:      unnamed       unused   input  active-high 
	line   4:      unnamed       unused   input  active-high 
	line   5:   "FRAM_WP#"       unused   input  active-high 
	line   6:    "EN_CL_1"       unused   input  active-high 
	line   7:    "EN_CL_2"       unused   input  active-high 
	line   8:    "EN_CL_3"       unused   input  active-high 
	line   9:    "EN_CL_4"       unused   input  active-high 
	line  10: "EN_ADC1_10V" unused input active-high 
	line  11: "EN_ADC2_10V" unused input active-high 
	line  12: "EN_ADC3_10V" unused input active-high 
	line  13: "EN_ADC4_10V" unused input active-high 
	line  14: "EN_SD_POWER" "?" output active-high [used]
	line  15: "EN_USB_HOST_5V" unused input active-high 
	line  16: "EN_OFF_BD_5V" unused input active-high 
	line  17: "EN_AUX_PWR"       unused   input  active-high 
	line  18: "EN_NIMBEL_3.3V" unused input active-high 
	line  19: "EN_GPS_PWR#" unused input active-high 
	line  20: "EN_CAN_XVR#" "en-can" output active-high [used]
	line  21: "EN_232_XVR"       unused   input  active-high 
	line  22: "EN_LS_OUT_1" unused input active-high 
	line  23: "EN_LS_OUT_2" unused input active-high 
	line  24: "EN_LS_OUT_3" unused input active-high 
	line  25: "EN_LS_OUT_4" unused input active-high 
	line  26: "EN_LS_OUT_5" unused input active-high 
	line  27: "EN_LS_OUT_6" unused input active-high 
	line  28: "EN_LS_OUT_7" unused input active-high 
	line  29:      unnamed       unused   input  active-high 
	line  30:      unnamed       unused   input  active-high 
	line  31:      unnamed       unused   input  active-high 
	line  32:   "DIG_IN_1"       unused   input  active-high 
	line  33:   "DIG_IN_2"       unused   input  active-high 
	line  34:   "DIG_IN_3"       unused   input  active-high 
	line  35:   "DIG_IN_4"       unused   input  active-high 
	line  36: "SD_BOOT_JMP#" unused input active-high 
	line  37:   "DIO_1_IN"       unused   input  active-high 
	line  38:   "DIO_2_IN"       unused   input  active-high 
	line  39:   "DIO_3_IN"       unused   input  active-high 
	line  40:   "DIO_4_IN"       unused   input  active-high 
	line  41:   "DIO_5_IN"       unused   input  active-high 
	line  42:   "DIO_6_IN"       unused   input  active-high 
	line  43:   "DIO_7_IN"       unused   input  active-high 
	line  44:      unnamed       unused   input  active-high 
	line  45:      unnamed       unused   input  active-high 
	line  46:      unnamed       unused   input  active-high 
	line  47:         "N7"       unused   input  active-high 
	line  48:         "P7"       unused   input  active-high 
	line  49:      unnamed       unused   input  active-high 
	line  50:      unnamed       unused   input  active-high 
	line  51:      unnamed       unused   input  active-high 
	line  52:      unnamed       unused   input  active-high 
	line  53:      unnamed       unused   input  active-high 
	line  54:      unnamed       unused   input  active-high 
	line  55:      unnamed       unused   input  active-high 
	line  56:      unnamed       unused   input  active-high 
	line  57:      unnamed       unused   input  active-high 
	line  58:      unnamed       unused   input  active-high 
	line  59:      unnamed       unused   input  active-high 
	line  60:      unnamed       unused   input  active-high 
	line  61:      unnamed       unused   input  active-high 
	line  62:      unnamed       unused   input  active-high 
	line  63:      unnamed       unused   input  active-high 

GPIOs into the CPU, such as those on the push switch near the row of LEDs (PUSH_SW_CPU#) and internal headers can generate interrupts and be used with gpiomon(1):

root@tsimx6:~# gpiomon 2 18
event: FALLING EDGE offset: 18 timestamp: [1643650592.848516846]
event:  RISING EDGE offset: 18 timestamp: [1643650593.225238304]
^Croot@tsimx6:~# 

One way of turning that into something useful would be by running it in a shell script:

while true ; do
      event=$(gpiomon --num-events=1 --falling-edge 2 18)
      echo "received $event"
      # do something
done
Note: DIO lines on the FPGA (gpiochip5) don't have their own interrupts, thus the gpiomon(1) command does not normally work for them.

GPS

The TS-7180 has an optional on-board Telit SL869 GPS receiver, accessible at /dev/ttymxc7, through which the GPS provides NMEA strings. An SMA female connector is provided for attaching an antenna.

The GPS power is controllable through a GPIO. For example:

gpioset 5 19=1 # turn on GPS
gpioset 5 19=0 # turn off GPS

By default, the GPS module is powered on when the board starts up.

A typical way of interfacing with the GPS is using gpsd. For example, under Debian, load these packages:

apt install gpsd gpsd-clients -y

Then edit /etc/default/gpsd and enable and/or change these two variables:

# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttymxc7"

# Other options you want to pass to gpsd
GPSD_OPTIONS="-n"

Then restart gpsd:

service gpsd restart

For testing, run gpsmon to see lock, coordinates, and time information.

You will likely want gpsd to start automatically at boot. To make this always happen, type:

systemctl enable gpsd

Finally, the following article describes writing clients that interface with gpsd, which can do so from most programming languages:

IMU

This board features an ST ISM330DLC, which provides both a 3-axis accelerometer and a gyroscope. The accelerometer has an acceleration range of ±2/±4/±8/±16 g. The gyroscope has a selectable angular range of ±125/±250/±500/±1000/±2000 dps. Linux provides access to both as part of the IIO subsystem (via iio-tools and libiio). They are accessed as ism330dlc_accel and ism330dlc_gyro, respectively.

ST ISM330 Accelerometer

This platform features an ST accelerometer / gyroscope. The accelerometer has an acceleration range of ±2/±4/±8/±16 g.

Early units were built using the "ism330dlc", and newer units are built using the "ism330dhcx". These are functionally the same and provide the same channels and performance, but IIO requires you to specify the part number. Our example python/c code will show how to work with either.

The accelerometer is accessed through IIO with channels:

  • accel_x
  • accel_y
  • accel_z
  • timestamp

For example:

# ISM330DHCX
iio_attr -c ism330dhcx_accel accel_x
iio_attr -c ism330dhcx_accel accel_y
iio_attr -c ism330dhcx_accel accel_z
# ISM330DLC
iio_attr -c ism330dlc_accel accel_x
iio_attr -c ism330dlc_accel accel_y
iio_attr -c ism330dlc_accel accel_z

The below examples will be written for the ism330dhcx_accel, but if this fails instead use the ism330dlc_accel device. These commands will provide a single sample of all of the values:

root@tsimx6ul:~# iio_attr -c ism330dhcx_accel accel_x
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'injection_raw', ERROR: Permission denied (-13)
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'raw', value '-183'
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'
root@tsimx6ul:~# iio_attr -c ism330dhcx_accel accel_y
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'injection_raw', ERROR: Permission denied (-13)
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'raw', value '-292'
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'
root@tsimx6ul:~# iio_attr -c ism330dhcx_accel accel_z
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'injection_raw', ERROR: Permission denied (-13)
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'raw', value '16491'
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'

To get the real world value, multiply the scale * the raw value. In this case:

  • X: -0.109434 g
  • Y: -0.174616 g
  • Z: 9.861618 g

The default scale is ±2, but ±2/±4/±8/±16 can be selected by setting the scale:

dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'

To set ±4, you would write the second available scale:

iio_attr -c ism330dhcx_accel accel_x scale 0.001196

The scale values are not independent on this device, and setting x/y/z will set the scale for all 3.

This driver also supports pulling continuous samples using the buffer interface. These can be accessed using iio_readdev:

iio_readdev ism330dhcx_accel -T 0 -s 128 > samples.bin

The format of this file is specified with iio_attr:

root@tsimx6ul:~# iio_attr -c ism330dhcx_accel
dev 'ism330dhcx_accel', channel 'accel_x' (input, index: 0, format: le:S16/16>>0), found 4 channel-specific attributes
dev 'ism330dhcx_accel', channel 'accel_y' (input, index: 1, format: le:S16/16>>0), found 4 channel-specific attributes
dev 'ism330dhcx_accel', channel 'accel_z' (input, index: 2, format: le:S16/16>>0), found 4 channel-specific attributes
dev 'ism330dhcx_accel', channel 'timestamp' (input, index: 3, format: le:S64/64>>0), found 0 channel-specific attributes

The samples are padded to the nearest 8-bytes, so this means the binary format is:

Bits Description
15:0 accel_x, little endian, signed
15:0 accel_y, little endian, signed
15:0 accel_z, little endian, signed
63:0 timestamp, little endian, signed
15:0 Padding

The unix utility hexdump supports formatting options which can parse these fields:

root@tsimx6ul:~# hexdump samples.bin --format '1/2 "X:%d " 1/2 "Y:%d " 1/2 "Z:%d " 1/8 "TS:%d" 1/2 "" "\n"' | head -n 4
X:-95 Y:-163 Z:8221 TS:200185381271666439
X:-107 Y:-147 Z:8248 TS:200190332264480519
X:-100 Y:-155 Z:8263 TS:200195283888013063
X:-95 Y:-159 Z:8253 TS:200200232540667655

This gives the raw values which can then be multiplied by the scale to get the real world value.

The IIO library can also be used to fill buffers with samples for processing. For example:

#!/usr/bin/env python3

import struct
import iio

ctx = iio.Context('local:')
ctx.set_timeout(0)
dev = ctx.find_device('ism330dhcx_accel') or ctx.find_device('ism330dlc_accel')

with open(f'/sys/bus/iio/devices/{dev.id}/sampling_frequency', 'w') as f:
	f.write(f"833.000")

for chan_name in ["accel_x", "accel_y", "accel_z"]:
	chn = dev.find_channel(chan_name)
	chn.enabled = True

# We will request 64 samples at a time
buffer = iio.Buffer(dev, 64, False)
# sample size (3x 16-bit signed data)
sample_size = 6
# Refill and process the buffer
buffer.refill()
data = buffer.read()
for i in range(0, len(data), sample_size):
	if i + sample_size <= len(data):
		x, y, z = struct.unpack('<hhh', data[i:i+sample_size])
		print(f'  accel_x={x}, accel_y={y}, accel_z={z}')

for chn in dev.channels:
	chn.enabled = False

This can also be done using the C library:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iio.h>

#define NUM_CHANNELS 3
#define SAMPLE_SIZE 6 // 3x 16-bit signed data (2 bytes per axis)

void process_samples(struct iio_buffer *buffer, size_t sample_size) {
    char *data = iio_buffer_start(buffer);
    size_t buffer_size = iio_buffer_end(buffer) - iio_buffer_start(buffer);
    int16_t x, y, z;

    for (size_t i = 0; i < buffer_size; i += sample_size) {
        memcpy(&x, &data[i], sizeof(x));
        memcpy(&y, &data[i + sizeof(x)], sizeof(y));
        memcpy(&z, &data[i + 2 * sizeof(x)], sizeof(z));
        printf("accel_x=%d, accel_y=%d, accel_z=%d\n", x, y, z);
    }
}

int main() {
    struct iio_context *ctx;
    struct iio_device *dev;
    struct iio_channel *channels[NUM_CHANNELS];
    struct iio_buffer *buffer;
    const char *channel_names[NUM_CHANNELS] = { "accel_x", "accel_y", "accel_z" };

    // Create context and find device
    ctx = iio_create_local_context();
    if (!ctx || !(dev = iio_context_find_device(ctx, "ism330dhcx_accel")) &&
        !(dev = iio_context_find_device(ctx, "ism330dlc_accel"))) {
        fprintf(stderr, "Unable to create context or find device\n");
        iio_context_destroy(ctx);
        return 1;
    }

    // Enable channels and set sampling frequency
    for (int i = 0; i < NUM_CHANNELS; i++) {
        channels[i] = iio_device_find_channel(dev, channel_names[i], false);
        if (!channels[i] || iio_channel_attr_write(channels[i], "sampling_frequency", "833.000") < 0) {
            fprintf(stderr, "Unable to find or configure channel %s\n", channel_names[i]);
            iio_context_destroy(ctx);
            return 1;
        }
        iio_channel_enable(channels[i]);
    }

    // Create buffer and process samples
    buffer = iio_device_create_buffer(dev, 64, false);
    if (!buffer || iio_buffer_refill(buffer) < 0) {
        fprintf(stderr, "Unable to create or refill buffer\n");
        iio_context_destroy(ctx);
        return 1;
    }

    process_samples(buffer, SAMPLE_SIZE);

    // Cleanup
    iio_buffer_destroy(buffer);
    iio_context_destroy(ctx);

    return 0;
}

ST ISM330 Gyroscope

This platform features an ST accelerometer / gyroscope. The gyroscope has a selectable angular range of ±125/±250/±500/±1000/±2000 dps

Early units were built using the "ism330dlc", and newer units are built using the "ism330dhcx". These are functionally the same and provide the same channels and performance, but IIO requires you to specify the part number. Our example python/c code will show how to work with either.

The gyroscope is accessed through IIO with channels:

  • anglvel_x
  • anglvel_y
  • anglvel_z
  • timestamp

For example:

# ISM330DHCX
iio_attr -c ism330dhcx_gyro anglvel_x
iio_attr -c ism330dhcx_gyro anglvel_y
iio_attr -c ism330dhcx_gyro anglvel_z
# ISM330DLC
iio_attr -c ism330dlc_gyro anglvel_x
iio_attr -c ism330dlc_gyro anglvel_y
iio_attr -c ism330dlc_gyro anglvel_z
root@tsimx6ul:~# iio_attr -c ism330dhcx_gyro anglvel_x
dev 'ism330dhcx_gyro', channel 'anglvel_x' (input), attr 'raw', value '2359'
dev 'ism330dhcx_gyro', channel 'anglvel_x' (input), attr 'scale', value '0.000153'
dev 'ism330dhcx_gyro', channel 'anglvel_x' (input), attr 'scale_available', value '0.000153 0.000305 0.000611 0.001222'
root@tsimx6ul:~# iio_attr -c ism330dhcx_gyro anglvel_y
dev 'ism330dhcx_gyro', channel 'anglvel_y' (input), attr 'raw', value '-1667'
dev 'ism330dhcx_gyro', channel 'anglvel_y' (input), attr 'scale', value '0.000153'
dev 'ism330dhcx_gyro', channel 'anglvel_y' (input), attr 'scale_available', value '0.000153 0.000305 0.000611 0.001222'
root@tsimx6ul:~# iio_attr -c ism330dhcx_gyro anglvel_z
dev 'ism330dhcx_gyro', channel 'anglvel_z' (input), attr 'raw', value '2761'
dev 'ism330dhcx_gyro', channel 'anglvel_z' (input), attr 'scale', value '0.000153'
dev 'ism330dhcx_gyro', channel 'anglvel_z' (input), attr 'scale_available', value '0.000153 0.000305 0.000611 0.001222'

This shows a snapshot of the x, y, z values. To get the real world value, multiply the scale * the raw value. In this case:

  • X: 0.360927 dps
  • Y: -0.255051 dps
  • Z: 0.422433 dps

The default scale is ±250, but ±250/±500/±1000/±2000 can be selected by setting the scale:

dev 'ism330dhcx_gyro', channel 'anglvel_z' (input), attr 'scale', value '0.000153'
dev 'ism330dhcx_gyro', channel 'anglvel_z' (input), attr 'scale_available', value '0.000153 0.000305 0.000611 0.001222'

To set ±1000, you would write the third available scale:

iio_attr -c ism330dhcx_gyro anglvel_z scale 0.000611

The scale values are not independent on this device, and setting x/y/z will set the scale for all 3.

This driver also supports pulling continuous samples using the buffer interface. These can be accessed using iio_readdev:

iio_readdev ism330dhcx_gyro -T 0 -s 128 > samples.bin

The format of this file is specified with iio_attr:

root@tsimx6ul:~# iio_attr -c ism330dhcx_gyro
dev 'ism330dlc_gyro', channel 'anglvel_x' (input, index: 0, format: le:S16/16>>0), found 3 channel-specific attributes
dev 'ism330dlc_gyro', channel 'anglvel_y' (input, index: 1, format: le:S16/16>>0), found 3 channel-specific attributes
dev 'ism330dlc_gyro', channel 'anglvel_z' (input, index: 2, format: le:S16/16>>0), found 3 channel-specific attributes
dev 'ism330dlc_gyro', channel 'timestamp' (input, index: 3, format: le:S64/64>>0), found 0 channel-specific attributes

The samples are padded to the nearest 8-bytes, so this means the binary format is:

Bits Description
15:0 anglvel_x, little endian, signed
15:0 anglvel_y, little endian, signed
15:0 anglvel_z, little endian, signed
63:0 timestamp, little endian, signed
15:0 Padding

The unix utility hexdump supports formatting options which can parse these fields into their raw values:

root@tsimx6ul:~# hexdump samples.bin --format '1/2 "X:%d " 1/2 "Y:%d " 1/2 "Z:%d " 1/8 "TS:%d" 1/2 "" "\n"' | head -n 40
X:-58 Y:-199 Z:24 TS:419695978925948679
X:-67 Y:-196 Z:29 TS:419701023781322503
X:-64 Y:-197 Z:28 TS:419705968690298631
X:-58 Y:-203 Z:29 TS:419711008204553991

The IIO library can also be used to fill buffers with samples for processing. For example:

#!/usr/bin/env python3

import struct
import iio

ctx = iio.Context('local:')
ctx.set_timeout(0)
dev = ctx.find_device('ism330dhcx_gyro') or ctx.find_device('ism330dlc_gyro')

with open(f'/sys/bus/iio/devices/{dev.id}/sampling_frequency', 'w') as f:
	f.write(f"833.000")

for chan_name in ["anglvel_x", "anglvel_y", "anglvel_z"]:
	chn = dev.find_channel(chan_name)
	chn.enabled = True

# We will request 64 samples at a time
buffer = iio.Buffer(dev, 64, False)
# sample size (3x 16-bit signed data)
sample_size = 6
# Refill and process the buffer
buffer.refill()
data = buffer.read()
for i in range(0, len(data), sample_size):
	if i + sample_size <= len(data):
		x, y, z = struct.unpack('<hhh', data[i:i+sample_size])
		print(f'  anglvel_x={x}, anglvel_y={y}, anglvel_z={z}')

for chn in dev.channels:
	chn.enabled = False

This can also be done using the C library:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iio.h>

#define NUM_CHANNELS 3
#define SAMPLE_SIZE 6 // 3x 16-bit signed data (2 bytes per axis)

void process_samples(struct iio_buffer *buffer, size_t sample_size) {
    char *data = iio_buffer_start(buffer);
    size_t buffer_size = iio_buffer_end(buffer) - iio_buffer_start(buffer);
    int16_t x, y, z;

    for (size_t i = 0; i < buffer_size; i += sample_size) {
        memcpy(&x, &data[i], sizeof(x));
        memcpy(&y, &data[i + sizeof(x)], sizeof(y));
        memcpy(&z, &data[i + 2 * sizeof(x)], sizeof(z));
        printf("anglvel_x=%d, anglvel_y=%d, anglvel_z=%d\n", x, y, z);
    }
}

int main() {
    struct iio_context *ctx;
    struct iio_device *dev;
    struct iio_channel *channels[NUM_CHANNELS];
    struct iio_buffer *buffer;
    const char *channel_names[NUM_CHANNELS] = { "anglvel_x", "anglvel_y", "anglvel_z" };

    // Create context and find device
    ctx = iio_create_local_context();
    if (!ctx || !(dev = iio_context_find_device(ctx, "ism330dhcx_gyro")) &&
        !(dev = iio_context_find_device(ctx, "ism330dlc_gyro"))) {
        fprintf(stderr, "Unable to create context or find device\n");
        iio_context_destroy(ctx);
        return 1;
    }

    // Enable channels and set sampling frequency
    for (int i = 0; i < NUM_CHANNELS; i++) {
        channels[i] = iio_device_find_channel(dev, channel_names[i], false);
        if (!channels[i] || iio_channel_attr_write(channels[i], "sampling_frequency", "833.000") < 0) {
            fprintf(stderr, "Unable to find or configure channel %s\n", channel_names[i]);
            iio_context_destroy(ctx);
            return 1;
        }
        iio_channel_enable(channels[i]);
    }

    // Create buffer and process samples
    buffer = iio_device_create_buffer(dev, 64, false);
    if (!buffer || iio_buffer_refill(buffer) < 0) {
        fprintf(stderr, "Unable to create or refill buffer\n");
        iio_context_destroy(ctx);
        return 1;
    }

    process_samples(buffer, SAMPLE_SIZE);

    // Cleanup
    iio_buffer_destroy(buffer);
    iio_context_destroy(ctx);

    return 0;
}

Jumpers

The TS-7180 has a set of jumpers located near the SuperCaps on the edge of the SBC.


These jumpers control a number of aspects of the TS-7180's behavior. The jumpers are labeled on the silkscreen rather than numbered:

Label Description
NO Charge When jumper is set, disable charging of the SuperCaps. Beneficial for early development and testing.
SD Boot When jumper is set, boot kernel and Debian from the SD card. Otherwise boot kernel and Debian from eMMC. This jumper influences U-Boot behavior.
U Boot When jumper is set, pause booting in U-Boot and drop to a U-Boot shell. Otherwise boot straight to Debian.
CAN When jumper is set, adds a 120 ohm termination resistor across CAN1 H and L pins. (Note: the CAN2 interface always has a 120 ohm termination)
485 When jumper is set, adds a 120 ohm termination resistor across RS-485 + and - pins.

LEDs

There are four LEDS on the TS-7180 that may be controlled by the user through the sysfs interface. These are colored yellow, green, red, and blue.

To turn an LED on, write a 1 to 'brightness'. To turn it off again, write a 0.

# Example:  Turn on the Blue LED...
echo 1 > /sys/class/leds/blue-led/brightness

# Turn it off again...
echo 0 > /sys/class/leds/blue-led/brightness

A number of triggers are also available for each LED, including timers, disk activity, and heartbeat. These allow the LEDs to represent various system activities as they occur. See the kernel LED documentation for more information on triggers and general use of LED class devices.

Magnetometer

This board includes an ST IIS2MDCTR 3-axis magnetometer, which has a magnetic field dynamic range of ±50 gauss (16 bits of precision at up to 150 Hz).

The magnetometer is accessed through Linux's industrial I/O (IIO) subsystem as lis2mdl_magn with channels:

  • magn_x
  • magn_y
  • magn_z
  • timestamp

For example:

root@tsimx6ul:~# iio_attr -c lis2mdl_magn -c magn_x
dev 'lis2mdl_magn', channel 'magn_x' (input), attr 'raw', value '630'
dev 'lis2mdl_magn', channel 'magn_x' (input), attr 'scale', value '0.001500'
root@tsimx6ul:~# iio_attr -c lis2mdl_magn -c magn_y
dev 'lis2mdl_magn', channel 'magn_y' (input), attr 'raw', value '-165'
dev 'lis2mdl_magn', channel 'magn_y' (input), attr 'scale', value '0.001500'
root@tsimx6ul:~# iio_attr -c lis2mdl_magn -c magn_z
dev 'lis2mdl_magn', channel 'magn_z' (input), attr 'raw', value '9'
dev 'lis2mdl_magn', channel 'magn_z' (input), attr 'scale', value '0.001500'

This shows a snapshot of the x, y, z values. To get the measured field strength along each axis, multiply the scale by the raw value to get the actual reading in milligauss. In the above example:

  • X: 0.945 mG (milligauss)
  • Y: -0.2475 mG
  • Z: 0.0135 mG

MicroSD Card Interface

The i.MX6ul SDHCI driver supports MicroSD (0-2GB), MicroSDHC (4-32GB), and MicroSDXC(64GB-2TB). The cards available on our website on average support up to 16MB/s read, and 22MB/s write using this interface. Sandisk Extreme cards with UHS support have shown 58MB/s Read and 59MB/s write. The linux driver provides access to this socket at /dev/mmcblk0 as a standard Linux block device.

This graph shows our SD write endurance test for 40 TS-7553 boards running a doublestore stress test on 4GB Sandisk MicroSD cards. A failure is marked on the graph for a card once a single bit of corruption is found.

Seethe IMX6ul reference manual for more information on this controller.

We have performed compatibility testing on the Sandisk MicroSD cards we provide, and we do not suggest switching brands/models without your own qualification testing. Though SD cards in theory will all follow the standard and just work, in practice cards vary significantly and can fail in subtle ways. We do not recommend ATP or Transcend MicroSD cards specifically due to known corruption issues that can occur after many GB of written data.

Our testing has shown that on average microSD cards will last between 6-12TB of written data before showing a single bit of corruption. This is enough for most applications to write for years and not see any issues, but for more reliable consider the eMMC which is expected to last over 100TB of writes. Higher end SD cards can also extend this, but industrial grade SD cards typically carry a cost much higher than the eMMC.

MicroSD cards should not be powered down during a write/erase cycle or you will eventually experience disk corruption. It is not always possible for fsck to recover from the types of failures that will be seen with SD power loss. The system should be designed to avoid power loss to SD cards, or the eMMC module should be used for storage instead which can be configured to be resilient to power loss.

Output Fault

The TS-7180 includes low side switches which can switch up to 500mA of current each, or up to 1A total. In the case where any output exceeds that the 1.25A it will trip the IO fault. When the FPGA detects a fault, it immediately turns off all low side switches.

This includes the 7 low side outputs on P3-A.

To monitor for fault, poll GPIO 30 on the FPGA:

gpioget 2-0028 62 # prints 1 if DIO are faulted, 0 if normal

If this signal goes high the fault has tripped and all of the low side switches have been disabled. This fault stays tripped until cleared.

To recover from a fault one can either perform a full system reboot, or clear the fault condition.

To clear the fault condition first reset all of the outputs.

gpioset 2-0028 22=0 # EN_LS_OUT_1
gpioset 2-0028 23=0 # EN_LS_OUT_2
gpioset 2-0028 24=0 # EN_LS_OUT_3
gpioset 2-0028 25=0 # EN_LS_OUT_4
gpioset 2-0028 26=0 # EN_LS_OUT_5
gpioset 2-0028 27=0 # EN_LS_OUT_6
gpioset 2-0028 28=0 # EN_LS_OUT_7

Next, pulse the clear signal.

gpioset 2-0028 31=1
gpioset 2-0028 31=0 # The clear occurs on this falling edge.

From here the IO could be turned on one at a time to check for the fault location.

PWM

WARNING: This requires FPGA Rev 11 or later

The TS-7180 provides a single PWM channel, available on DIO_1 (pin #1 of P3-A). Because DIO_1 is a general-purpose IO, to use it as a PWM output it is first necessary to enable such usage by writing to address 309 in the FPGA, as follows:

tshwctl -a 309 -w 1

PWM devices are available though the sysfs filesystem, they will appear at "/sys/class/pwm/pwmchipX/" where X is the PWM channel number. Due to the layout of the PWM controller, each PWM channel is on a separate chip. Normally a single PWM chip can support multiple PWM devices through linux, however in this case each chip only has a single device; pwm0. This device is not enabled by default and must be turned on manually: can be used to control the PWM.

# Each PWM controller has "1" PWM device which will be PWM channel 0
echo 0 > /sys/class/pwm/pwmchipX/export

This will create a pwm0/ directory under each pwmchipX/ directory which will contain the following relevant files.:

period Total period, inactive and active time in the PWM cycle specified in nanoseconds.
duty_cycle Active time of the PWM signal specified in nanoseconds. Must be less than the period.
enable Write 1 to enable, 0 to disable

As an example, this will set a 50khz signal with 50 percent duty cycle on PWM channel 4:

# 20us is the period for 50khz
echo 20000 > /sys/class/pwm/pwmchip4/pwm0/period
echo 10000 > /sys/class/pwm/pwmchip4/pwm0/duty_cycle
echo 1 > /sys/class/pwm/pwmchip4/pwm0/enable


Note: The DIO pins on the TS-7180 have a 1.5k pull-up, which means that the rise-time on these outputs is relatively slow. Therefore, you might need to add an off-board pull-up to get a faster rise-time.

Quadrature & Edge-Counters

Quadrature Counters

The TS-7180 provides three independent quadrature counters. The associated inputs are shown in the table below.

Quadrature
Quad # INPUTS
Quad0 DIG_IN_1 + DIG_IN_2
Quad1 DIG_IN_3 + DIG_IN_4
Quad2 DIO_6_IN + DIO_7_IN


Each of the quadrature counters (which are in the FPGA) is 16-bits wide, and are accessed via i2c. The addresses are shown below.


Quad # MSB LSB MSB Alias
Quad0 96 97 98
Quad1 99 100 101
Quad2 102 103 104


For example, to read the MSB for Quad1:

tshwctl -r -a 99


The MSB aliases are used to detect 16-bit rollover. If the first reading of the MSB is not equal to the second, overflow/underflow was detected during the read.


Edge-Counters, Period-counters


For each input pin, there is an edge-counter, and a period-counter. The former counts the positive edges on an input pin, while the latter may be used to measure the elapsed time between N positive-edges.

Edge-counters are 16-bits wide, and their addresses are shown in the table below.

Edge Counters
Input MSB LSB MSB Alias
DIG_IN_1 105 106 107
DIG_IN_2 108 109 110
DIG_IN_3 111 112 113
DIG_IN_4 114 115 116
DIO_6_IN 117 118 119
DIO_7_IN 120 121 122


Period counters are 32-bits wide, and their addresses are shown in the table below.

Period Counters
Input Byte 3 Byte 2 Byte 1 Byte 0
DIG_IN_1 131 132 133 134
DIG_IN_2 135 136 137 138
DIG_IN_3 139 140 141 142
DIG_IN_4 143 144 145 146
DIO_6_IN 147 148 149 150
DIO_7_IN 151 152 153 154

To use the period counters, it is first necessary to write N (for the number of edges to count) to address 155. This may be done like so:

tshwctl -a 155 -w N

As soon as address 155 is written, counting begins, clocked at 63MHz. After N edges have been detected, the period registers may be read. The frequency of the input may be calculated from the period, as shown here:

frequency = (N * 63000000) / period


Technologic Systems has provided a simple test program for accessing and displaying the values from the quadrature and edge-counters. Download the source tarball here: File:Test-edges.tar.gz

RTC

The TS-7180 includes an ST M41T00S low-power serial real-time clock (RTC) with battery-backup. This is /dev/rtc0 in our images, and is accessed using the standard hwclock command.

Serial Ports

The TS-7180 provides three standard RS-232 ports, and one RS-485 port. A fourth RS-232 port is a non-standard option. All of these ports are presented on the P5 connector. The RS-485 port has auto-transmit-enable and an on-board terminator that may be enabled by installing the "485" jumper (adjacent to the RTC battery).

RS-232 ports 1 through 3

UART Linux /dev Connection on Terminal Block P5-A To "steal [1]" TX pin RX pin
UART2 ttymxc1 TX2/RX2 5 6
UART5 ttymxc4 TX1/RX1 2 3
UART7 ttymxc6 TX3/RX3 (unless "stolen") 4 7 8
  1. Writing this value to FPGA address 307 or 308 takes over this UART device for the cell modem or HD12, respectively. While "stolen", this physical RS-232 connection no longer possesses a UART device.
Note: The RS-232 transceiver chip on the board must be enabled before those ports can be used. This is done by running the command tshwctl -a 21 -w 3.

RS-485

UART 485+ 485-
ttymxc3 P5-13 P5-14

RS-485 on the P5 terminal block is accessible via /dev/ttymxc3, unless that device is "stolen" for RS-232 on the XBee/Nimbelink/MultiTech sockets or the HD12 header.

RS-232 port 4 (optional)

Custom boards may provide a fourth RS-232 port on P5, taking over the pins that by default are assigned to the second CAN controller. In this case, the pinout of the additional RS-232 port is:

UART TX RX
ttymxc7 P5-10 P5-11


The daughter-card interface (HD12 header) contains TTL-level TX/RX pins that may be used to connect to a CPU UART, with the caveat that to do so, one of the assigned UARTs must be reassigned to the header. The reassignment is done by writing to the register at address 308 in the FPGA. The table in the FPGA Registers section shows which UARTs may be reassigned. By default, the HD12 TX/RX pins are not connected to any UART.

Sleep mode

This board implements a low power sleep mode using the onboard supervisory microcontroller. The microcontroller is able to power off the remainder of the board while only drawing a few mW. This is effectively a shutdown/startup for Linux to startup/resume from this low power sleep.

The board can wake three ways:

  • Timer – A number of milliseconds are specified for a sleep. 1000 ms minimum to 4294967295 ms (49.7 days) maximum.
  • SW1 – Pressing the button on the side of the board.
  • P5-B pin 8 WAKE_UP is asserted (over 1.5V) – This signal is active high and supports 0-40 V input, such as an ignition switch.

The sleep mode can be entered by calling silabs sleep 60000 to sleep for 60 seconds, but this should never be called directly from a Linux shell prompt (from a U-Boot prompt is OK). This would be equivalent to disconnecting power while booted which can cause data loss.

The Debian distribution uses systemd to manage shutdown. When systemd shuts down it will call all executables in the "/lib/systemd/system-shutdown/". Create a script with the name of "silabs-sleep" in said directory with these contents:

cat > /lib/systemd/system-shutdown/silabs-sleep <<EOF
#!/bin/bash

if [ "$1" != "reboot" ]; then
        silabs sleep 60000
fi
EOF
chmod a+x /lib/systemd/system-shutdown/silabs-sleep

Now the board will sleep immediately following a shutdown. For example:

shutdown -h now

The board will power off on shutdown, and 60 seconds later automatically power back up.

SPI

The i.MX6UL CPU has a native SPI peripheral that is used in a number of places on the TS-7180. Additionally, kernel spidev support is added to allow SPI access from userspace. User SPI can be used fora generic SPI connection on HD12, as well as user accessible FRAM.

The ECSPI peripheral in the i.MX6UL CPU is highly flexible and can even support SPI slave mode. For more information on the peripheral itself, please see the CPU reference manual.


The SPI peripheral is accessible as /dev/spidev2.x, where "x" is one of the three chip select lines. Additional chip select lines can be implemented if needed by adding them to the kernel device-tree by using GPIO.

CS Device
0 Reserved for FPGA
1 HD12
2 FRAM

See the kernel spidev documentation for more information on interfacing with the SPI peripherals.

TS-SILO Supercapacitors

The TS-7180 has an option to add two 2.7 V 25 F supercapacitors. These two supercapacitors can provide up to 20 seconds of power hold time automatically if the external power input is removed. The Power Fail input signal (see the DIO Section) can be used to determine if the exterior power has been removed or fallen below a valid input level. Using this signal, a proper reboot can be issued to ensure that all data is flushed from cache to disk, and all disks are unmounted properly.

Using a reboot is important as issuing a shutdown command will put the kernel in a halted state with no way to cycle it back on so long as the supercapacitors are providing backup power. A reboot will get the system back to the U-Boot shell which by default will monitor the Power Fail input and will only continue to boot to the operating system if input power is valid.

TS-SILO charge and discharge is managed transparently by the supervisory microcontroller. A jumper is provided to disable the charging and use of the supercapacitors. This mode is very useful for development to allow for proper power-off conditions without having to wait for the supercapacitors to discharge. The supervisory microcontroller will also not allow the TS-7180 to boot if power input is invalid. If the system reboots safely due to a power failure, it will remain in the bootloader until external power is re-applied.

By default, systemd(1) loads tssilomon.service when Debian starts up. The service monitors the POWER_FAIL pin and attempts a graceful reboot if the power input has failed. This service runs the script /usr/local/bin/tssilomon to perform the monitoring.

Additionally, U-Boot can delay booting until the supercapacitors are charged to a certain percentage, optionally printing the current percentage once per second. These are controlled with the environment variables chrg_pct and chrg_verb. By setting chrg_pct to anything other than 0 (meaning "do not wait," which is the default behavior), booting will be delayed until that percentage is reached. Setting chrg_verb environment variable to 1 will enable the verbose printing of the current percentage every second. Note that the supercapacitors may be at 0% for a large period of time, this is due to the charge level being below a voltage that can sustain the TS-7180. See the U-Boot section for information on setting environment variables.

A recommended value is 100%. This value was chosen because it can ensure the system is powered long enough to boot up and safely reboot if power is immediately cut once booting has started (and provide an additional 8 s of power). Please note that this only applies to the default stock image; any further changes to the TS-7180 hardware or software, such as connecting powered devices like USB or adding additional applications may cause the recommended value to not sustain the TS-7180 until a safe reboot is completed. The time it takes to reach 100% charge will vary depending on the current charge of the supercapacitors. On average, it will take about 20 seconds to charge the supercapacitors to 100%; this is assuming the supercapacitors have very recently fallen below the threshold voltage to sustain the TS-7180.

Note: We strongly recommend disabling supercapacitors during development! If the supercapacitors are charged and a shutdown command is issues, the unit may require up to an hour of time with all external power removed in order to discharge the supercapacitors enough to allow the unit to power back on.

TWI

The i.MX6 supports standard I²C at 100 kHz, or using fast mode for 400 kHz operation. The CPU is connected to two I²C buses on the TS-7180.

I2C1 is internal to the TS-7180 and connects to the onboard Silabs supervisory microcontroller at 100 kHz; and to the onboard ST M41T00S real-time clock (RTC).

/dev/i2c-0
Address Device
0x4a #Silabs
0x68 #RTC

The second I²C bus, I2C3, is connected to the onboard FPGA, for communication between it and the CPU. This bus also runs at 400 kHz by default.

/dev/i2c-2
Address Device
0x28-0x2f #FPGA


In addition to the CPU I²C buses, a bit-banged I²C interface is available on the daughter-card interface, using gpio. The following command will instantiate (create a device node for) a new ssd1306 display at I²C address 0x3C:

  echo ssd1306 0x3c > /sys/bus/i2c/devices/i2c-4/new_device

Once this is done, i2c-tools can manipulate the I²C device, or a the downstream developer can write their own client. Technologic Systems has provided a simple client program for writing to an SSD1306 OLED display connected to the HD12 connector. The photo below shows output on the display.

Download the source-code tarball here: File:Ssd1306-demo.tar.gz


Note: It is also possible to request the kernel to bitbang additional I²C buses as needed. See an example here.

The kernel makes the I²C available at /dev/i2c-#, where "#" is 0, 2, or 4. You can use the i2c-tools (i2cdetect, i2cget, i2cset), or you can write your own client.

USB

The TS-7180 has both a Host connector and a Device connector.

USB Host

The TS-7180 provides a standard USB 2.0 host supporting 480Mb/s. Typically this is interfaced with by using standard Linux drivers, but low level USB communication is possible using libusb.

USB DEVICE

The USB type B device port is connected to the onboard Silabs for USB to serial console.

Watchdog

The kernel provides an interface to the watchdog driver at /dev/watchdog. Refer to the kernel documentation for more information:

WIFI

The TS-7180 uses an Atmel ATWILC3000-MR110CA IEEE 802.11 b/g/n Link Controller Module With Integrated Bluetooth® 4.0. Linux provides support for this module using the wilc3000 driver.

Summary features:

  • IEEE 802.11 b/g/n RF/PHY/MAC SOC
  • IEEE 802.11 b/g/n (1x1) for up to 72 Mbps PHY rate
  • Single spatial stream in 2.4GHz ISM band
  • Integrated PA and T/R Switch Integrated Chip Antenna
  • Superior Sensitivity and Range via advanced PHY signal processing
  • Advanced Equalization and Channel Estimation
  • Advanced Carrier and Timing Synchronization
  • Wi-Fi Direct and Soft-AP support
  • Supports IEEE 802.11 WEP, WPA, and WPA2 Security
  • Supports China WAPI security
  • Operating temperature range of -40°C to +85°C

External Interfaces

Power Connector

The power connector, CN7, is shown in the photograph below. This accepts an 8-28 VDC input.

Terminal Blocks

The TS-7180 includes four removable terminal blocks (OSTTJ0811030) for UARTs, CAN, ADC, and other general purpose IO. The low side switch outputs on these IO also feature a detectable fault under overcurrent conditions.

P5-A
Pin # Description
1 Ground
2 RS-232_STC_TXD (/dev/ttymxc4)
3 RS-232_STC_RXD (/dev/ttymxc4)
4 Ground
5 RS-232_STC_TXD (/dev/ttymxc1)
6 RS-232_STC_RXD (/dev/ttymxc1)
7 RS-232_STC_TXD (/dev/ttymxc6)
8 RS-232_STC_RXD (/dev/ttymxc6)
P5-B
Pin # Description
1 Ground
2 STC_CAN_2_H (can2 interface)[1]
3 STC_CAN_2_L (can1 interface)[2]
4 Ground
5 STC_485+ (/dev/ttymxc3)
6 STC_485- (/dev/ttymxc3)
7 Ground
8 WAKE-UP / gpio bank 2 io 18
  1. RS-232_STC_TXD (/dev/ttymxc5) depending on option
  2. RS-232_STC_RXD (/dev/ttymxc5) depending on option
P3-A
Pin # Description
1 DIO_1_IN gpio bank 5 io 37 / EN_LS_OUT_1 gpio bank 5 io 21 [1]
2 DIO_2_IN gpio bank 5 io 38 / EN_LS_OUT_2 gpio bank 5 io 22 [1]
3 DIO_3_IN gpio bank 5 io 39 / EN_LS_OUT_3 gpio bank 5 io 23 [1]
4 DIO_4_IN gpio bank 5 io 40 / EN_LS_OUT_4 gpio bank 5 io 24 [1]
5 DIO_5_IN gpio bank 5 io 41 / EN_LS_OUT_5 gpio bank 5 io 25 [1]
6 DIO_6_IN gpio bank 5 io 42 / EN_LS_OUT_6 gpio bank 5 io 26 [1]
7 DIO_7_IN gpio bank 5 io 43 / EN_LS_OUT_7 gpio bank 5 io 27 [1]
8 DIG_IN_3_STC gpio bank 5 io 0
9 DIG_IN_3_STC gpio bank 5 io 1
10 Ground
11 Ground
12 Ground
P3-B
Pin # Description
1 STC_CAN_1_H (can1 interface)
2 STC_CAN_1_L (can1 interface)
3 AN_IN_1 (ADC)
4 AN_IN_2 (ADC)
5 AN_IN_3 (ADC)
6 AN_IN_4 (ADC)
7 DIG_IN_3_STC gpio bank 5 io 2
8 DIG_IN_4_STC gpio bank 5 io 3
9 5V
10 Ground
11 Ground
12 Ground
  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 These low side switches can sink 500mA. Set the output gpio to 1 to enable the sink, or 0 to disable or read the 0-30V input.

Multitech Socket

The Multitech socket supports Multitech's Socketmodem modules to provide cell connectivity.

This header is compatible with the USB or serial based modules. The Multitech header supports up to 64 pins, but the TS-7180 only connects the pins it needs to support the modules.

Turn on a cell modem with:

gpioset 5 17=1
Signals Pin Layout
Pin Signal
24 MT_RESET [1]
25 USB_VBUS / CELL_MODEM_5V
26 GND
27 USB_MULTI_P
28 USB_MULTI_N
33 N/C
34 RXD_MODEM_5V [2] [3]
35 TXD_MODEM [3]
36 N/C
37 N/C
38 N/C
39 N/C
40 GND
41 GND
59 N/C
60 N/C
61 CELL_MODEM_5V [4]
62 N/C
63 GND

Nimbelink Socket

The CN5 header is a 2mm pitch 2x10 header which supports XBEE form factor modules. These include NimbeLink and Digi cell modems, Zigbee, Digi mesh, and other third party radios.

For Cell radios that use USB this must be enabled. This turns off USB to the bottom port on the dual high type A connector. Only enable if this is compatible with your module:

# Turn on the USB
gpioset 2 12=0

This header can provide 3.3V or 4V as some cell radios require higher voltage. Check the datasheet of your module before turning on any power to this header. Most cell modems require 4V, while most other radios require 3.3V.

# Only turn on one at a time.
# For 4V modules:
gpioset 5 17=1

# For 3.3V modules:
# gpioset 5 18=1

Many NimbeLink modems require NIMBEL_PWR_ON to be toggled before they "turn on". If one thinks of turning on the power (above) as "attaching the battery" of a cellphone, toggling NIMBEL_PWR_ON is analogous to "pressing the power button" for a second. Here's a script to do exactly that.

gpioset 2 19=1
sleep 1
gpioset 2 19=0

If your device doesn't turn on or off as expected, be sure to consult the manual for it. There are often device-specific procedures for powering on and sometimes even custom AT command sequences needed in order to safely power off.

By default there is no UART mapped to this header. Map ttymxc2 with:

tshwctl --addr 307 --poke 1 # Claim bluetooth UART3 (ttymxc2) for modem

See the #FPGA Registers address 307 for more UART options.


For serial modules refer to these related links:

This sample code can be used to verify connectivity to the serial-based XBee modules:

wget https://files.embeddedTS.com/ts-arm-sbc/ts-7840-linux/samples/xbeetest.c
gcc xbeetest.c -o xbeetest

gpioset 5 18=1 # Turn on only 3.3V
tshwctl --addr 307 --poke 1 # Claim bluetooth UART3 (ttymxc2)
./xbeetest /dev/ttymxc2

This will print out the module information such as:

XBee3 Zigbee TH RELE: 100A
Build: Apr 16 2020 19:00:33
HV: 424E
Bootloader: 181 Compiler: 8030001
Stack: 6710
OK
Signals Pin Layout
Pin Signal
1 VCC (XBEE_3.3V or NIMBEL_4.7V)
2 RXD_MODEM_5V [5] [6]
3 TXD_MODEM_3.3V [6]
4 GND
5 NC
6 NIMBEL_4.7V
7 USB_MULTI_P
8 USB_MULTI_N
9 GND
10 GND
11 GND
12 XBEE_CTS / GPIO bank 2 io 15
13 NC
14 3.3V VREF
15 GND
16 GND
17 NC
18 NC
19 NC
20 NIMBEL_PWR_ON / GPIO bank 2 io 19

  1. Connected to the FPGA, but presently not supported. Sampled datasheet does not require this to be driven and will default out of reset.
  2. This is a 5V tolerant TTL UART input.
  3. 3.0 3.1 By default, no uart is mapped here. These are remapped through fpga reg 307. For example, to remap UART3(/dev/ttymxc2) run "tshwctl --addr 308 --poke 1"
  4. Turn on power with "gpioset 5 17=1"
  5. This is a 5V tolerant TTL UART input.
  6. 6.0 6.1 By default, no uart is mapped here. These are remapped through fpga reg 307. For example, to remap UART3(/dev/ttymxc2) run "tshwctl --addr 308 --poke 1"

HD8 Header

The TS-7180 Daughter Card Interface (HD8) may be used to connect a variety of off-board peripherals.

Signals Pin Layout
HD8
Pin Description
1 VIN
2 POE_78 [1]
3 GND
4 POE_45 [1]
5 GND
6 POE_TX [1]
7 HD1_SPI_CS [2]
8 POE_RX [1]

  1. 1.0 1.1 1.2 1.3 The POE pins can be used with a daughtercard to add POE support to the TS-7180.
  2. This is a 5V tolerant input that can be read through gpio bank 2 io 10. As an output this is connected to gpio bank 2 io 0. The output by default is connected to /dev/spidev2.1. See the #SPI section for more details.

HD12 Header

Signals Pin Layout
HD12
Pin Description
1 /dev/i2c-4 DAT
2 RXD_HD1_5V [1] [2]
3 USB-
4 TXD_HD1_3V [2]
5 USB+
6 /dev/i2c-4 CLK
7 +5V
8 +5V
9 SPI_3_MISO (/dev/spidev 2.1)
10 SPI_3_MOSI (/dev/spidev 2.1)
11 3.3V
12 SPI_3_CLK (/dev/spidev 2.1)

  1. This is a 5V tolerant TTL UART input.
  2. 2.0 2.1 By default, no uart is mapped here. These are remapped through fpga reg 308. For example, to remap UART8(/dev/ttymxc7) run "tshwctl --addr 308 --poke 5"

Specifications

Power Consumption

All tests are performed at 12V, with Ethernet, USB, supercaps, SD, disconnected or disabled unless otherwise specified.

TS-7180-SRW9I
Test Average Max
Idle 49mA/0.59W 148mA/1.78W
Idle with one Ethernet connected 76mA/0.91W 139mA/1.67W
Idle with both Ethernets connected 105mA/1.20W 156mA/1.87W
Idle CPU booting with Supercaps Enabled 51.1mA/0.61W[1] 531mA/6.37W
Busy CPU (openssl speed) 113mA/1.36W 156mA/1.87W
Sleep Mode 1.8mA/22mW 58mA/70mW
  1. Draws near peak and approaches typical power consumption over a minute as caps charge.

TS-7180 Revisions and Changes

PCB Revisions

Revision Description
C Initial sampling revision
D All Rev C fixes plus SD card socket moved slightly for clearance.

U-Boot Revisions

Depending on context, you can determine your U-Boot revision in one of several ways:

1. The U-Boot build date can be viewed as the first line of USB console output when the unit is powered on. For example:

U-Boot 2016.03-00408-gd450758c91 (Oct 10 2019 - 11:59:08 -0700)

CPU:   Freescale i.MX6UL rev1.2 at 396 MHz
...

2. U-Boot has a version command that outputs similar version information to what is shown above.

3. At a Linux shell, the following command prints the version strings of any U-Boot and/or SPL image that is present in eMMC:

strings /dev/mmcblk1boot0 | grep '^U-Boot .*(.*)'

The output is the same string(s) that will be printed on the console at board startup.


Version Description of changes
U-Boot 2016.03-14615-g4047d08843 (Dec 07 2018 - 14:16:47 -0800) Engineering Sample Program release.
U-Boot 2020.01-40204-gde7a0755e9 (Jan 11 2022 - 15:22:14 -0700) Transition to U-Boot v2020.01
U-Boot 2020.01-40207-ge5e6ccfb43 (Feb 07 2022 - 11:26:23 -0700)
  • fixes related to booting from SD card,
  • puts the push-switch-at-startup (jpsw) and other jumper settings into environment variables that can be used by boot scripts
  • now uses that mechanism, rather than compiled code, to honor the U-Boot and SD Boot jumpers
U-Boot 2020.01-40238-g06466887a9 (Aug 05 2024 - 19:13:43 +0000)
  • Added distro boot support.
20240820
  • Detects the accelerometer+gyro present and updates the device tree before jumping to linux
    • Supports the existing ism330dlc, and the new ism330dhcx

FPGA Revisions

Version Description
13 Engineering Sampling release version.
14 REV C board support
15 GPS PPS passthrough to FPGA_IRQ to support the pps_gpio driver
16
  • MT_RESET#, with pull-up, for better Multi-Tech modem support.
  • Mux of eight P3 pins into CPU GPIO chip 0 line 18, enabling their transactions to be detected via gpiomon.
17
  • Implemented DIO_FAULT# circuit breaker
  • Improved accuracy of 32 kHz clock for WiFi/Bluetooth.

Supervisory Microcontroller (SMC) Firmware Revisions

Version Description
6 Initial REV C support
7 Adds support for PUSH_SW/WAKE_UP. This lets the silabs sleep mode wake up early if SW1 or WAKE_UP is asserted.
8 Un-released (source code clean-up, binary identical to 7).
9 Same as {7, 8}, but ported from the Silabs F381 to run (only) on the EFM8.

Root Filesystem Software Images

Debian Changelog

See our Debian release archive for all released images, including the latest for each supported Debian version.

TS-7180 Debian Changelog

Product Notes

FCC Advisory

This equipment generates, uses, and can radiate radio frequency energy and if not installed and used properly (that is, in strict accordance with the manufacturer's instructions), may cause interference to radio and television reception. It has been type tested and found to comply with the limits for a Class A digital device in accordance with the specifications in Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference when operated in a commercial environment. Operation of this equipment in a residential area is likely to cause interference, in which case the owner will be required to correct the interference at his own expense.

If this equipment does cause interference, which can be determined by turning the unit on and off, the user is encouraged to try the following measures to correct the interference:

Reorient the receiving antenna. Relocate the unit with respect to the receiver. Plug the unit into a different outlet so that the unit and receiver are on different branch circuits. Ensure that mounting screws and connector attachment screws are tightly secured. Ensure that good quality, shielded, and grounded cables are used for all data communications. If necessary, the user should consult the dealer or an experienced radio/television technician for additional suggestions. The following booklets prepared by the Federal Communications Commission (FCC) may also prove helpful:

How to Identify and Resolve Radio-TV Interference Problems (Stock No. 004-000-000345-4) Interface Handbook (Stock No. 004-000-004505-7) These booklets may be purchased from the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402.

Limited Warranty

See our Terms and Conditions for more details.

Trademarks

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