TS-7250: Difference between revisions

From embeddedTS Manuals
(Initial conversion from PDF to WIKI)
(Initial conversion from PDF to WIKI)
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PLD provides glue logic, watchdog timer, Compact Flash IDE, and 8 bit PC/104 support.
PLD provides glue logic, watchdog timer, Compact Flash IDE, and 8 bit PC/104 support.
Integer CPU performance is about 20% faster than our 133 Mhz x86 offerings.
Integer CPU performance is about 20% faster than our 133 Mhz x86 offerings.
Even with the standard power consumption of 2 Watts, the TS-72XX SBC�s run without
Even with the standard power consumption of 2 Watts, the TS-72XX SBC's run without
fans or heat sinks in the temperature range of -20� to +70�C. Extended Temperature -40�
fans or heat sinks in the temperature range of -20 to +70°C. Extended Temperature -40°
to +85�C is also standard, but CPU clock must be decreased to about 166MHz for higher
to +85°C is also standard, but CPU clock must be decreased to about 166MHz for higher
temperatures. Digital Signal Processing (DSP) is enabled through a standard 5 channel,
temperatures. Digital Signal Processing (DSP) is enabled through a standard 5 channel,
12bit A/D converter (Optional 8 channel, 12 bit A/D converter), 20 DIO lines and 2
12bit A/D converter (Optional 8 channel, 12 bit A/D converter), 20 DIO lines and 2
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The 8/16 bit PC/104 interface enables additional functionality through Technologic
The 8/16 bit PC/104 interface enables additional functionality through Technologic
Systems� broad product line of PC/104 peripheral daughter boards. The TS-7KV adds
Systems' broad product line of PC/104 peripheral daughter boards. The TS-7KV adds
video, CAN, Com Ports, and A/D conversion. The TS-ETH10 allows the addition of
video, CAN, Com Ports, and A/D conversion. The TS-ETH10 allows the addition of
Ethernet ports. The TS-CAN adds CAN connectivity. The TS-Modem boards add both
Ethernet ports. The TS-CAN adds CAN connectivity. The TS-Modem boards add both
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KB data cache to provide zero-cycle latency to the current program and data, or they can
KB data cache to provide zero-cycle latency to the current program and data, or they can
be locked to guarantee no-latency access to critical sections of instructions and data. For
be locked to guarantee no-latency access to critical sections of instructions and data. For
applications with instruction-memory size restrictions, the ARM920T�s compressed Thumb
applications with instruction-memory size restrictions, the ARM920T's compressed Thumb
instruction set can be used to provide higher code density and lower Flash storage
instruction set can be used to provide higher code density and lower Flash storage
requirements.
requirements.
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* Single +5VDC power supply @ 450 mA
* Single +5VDC power supply @ 450 mA
* Small size 3.8 x 4.5 inches (9.7 x 11.5 cm)
* Small size 3.8 x 4.5 inches (9.7 x 11.5 cm)
* Operating Temperature Range: Fanless from -20� to +70�C
* Operating Temperature Range: Fanless from -20° to +70°C
* Extended Temperature -40� to +85�C standard at lower CPU clock speeds (166MHz)
* Extended Temperature -40° to +85°C standard at lower CPU clock speeds (166MHz)


== Configurability ==
== Configurability ==
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=== On-board Options ===
=== On-board Options ===
* TS-7xxx-yyy-zzzF: up to �yyy� MB of on-board SDRAM and �zzz� MB of Flash memory
* TS-7xxx-yyy-zzzF: up to 'yyy' MB of on-board SDRAM and 'zzz' MB of Flash memory
upgrade for TS-7xxx board models. For example, TS-7250-64-128F selects model TS-
upgrade for TS-7xxx board models. For example, TS-7250-64-128F selects model TS-
7250 upgrade with 64 MB of SDRAM and 128 of NAND Flash.
7250 upgrade with 64 MB of SDRAM and 128 of NAND Flash.
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functionalities includes:
functionalities includes:
* NVRAM - adds 32K, 128K, 1MB or 2MB bytes of battery-backed SRAM. Battery backed SRAM provides non-volatile memory with very fast write times and unlimited write cycles, unlike Flash memory. This can be very important if the data is constantly being updated several times per minute, since Flash devices can wear-out after a few million write cycles. It also eliminates the latency that Flash memory has during write cycles. This resource is a byte-wide memory device using a lithium battery that will last a minimum of 10 years with or without power applied.
* NVRAM - adds 32K, 128K, 1MB or 2MB bytes of battery-backed SRAM. Battery backed SRAM provides non-volatile memory with very fast write times and unlimited write cycles, unlike Flash memory. This can be very important if the data is constantly being updated several times per minute, since Flash devices can wear-out after a few million write cycles. It also eliminates the latency that Flash memory has during write cycles. This resource is a byte-wide memory device using a lithium battery that will last a minimum of 10 years with or without power applied.
* Analog VIDEO interface � When a video monitor is needed.
* Analog VIDEO interface - When a video monitor is needed.
* CAN Bus � Useful for automotive applications.
* CAN Bus - Useful for automotive applications.
* Modems � Phone Line or GSM Cellular modems.
* Modems - Phone Line or GSM Cellular modems.
* Additional Ethernet ports.
* Additional Ethernet ports.
* Additional DIO interface with either 24 or 64 new lines..
* Additional DIO interface with either 24 or 64 new lines..
* Additional 12 bit ADC and DAC: useful for industrial automation applications.
* Additional 12 bit ADC and DAC: useful for industrial automation applications.
* Additional COM and Parallel ports � Make more communication channels available.
* Additional COM and Parallel ports - Make more communication channels available.
* Power-over-Ethernet
* Power-over-Ethernet
* Radios � Long-range wireless radios, Xbee modules
* Radios - Long-range wireless radios, Xbee modules


{{note|New PC/104 boards are always in development. Contact Technologic Systems or visit the PC/104 peripherals page at our website for a complete and updated list of additional functionalities that can be added to the TS-7250 using the PC/104 bus. You can also contact Technologic Systems about your [http://www.embeddedarm.com/services/custom-design.php custom project design].}}
{{note|New PC/104 boards are always in development. Contact Technologic Systems or visit the PC/104 peripherals page at our website for a complete and updated list of additional functionalities that can be added to the TS-7250 using the PC/104 bus. You can also contact Technologic Systems about your [http://www.embeddedarm.com/services/custom-design.php custom project design].}}
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  $ fconfig -l
  $ fconfig -l


The defaults can be changed by simply entering �fconfig� at the RedBoot prompt and
The defaults can be changed by simply entering 'fconfig' at the RedBoot prompt and
answering the prompts. A final chance to write or discard the changes to the board will be
answering the prompts. A final chance to write or discard the changes to the board will be
given by RedBoot.
given by RedBoot.
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After loading the kernel, the default script then executes the kernel with the following
After loading the kernel, the default script then executes the kernel with the following
command:
command:
  $ exec -c "console=ttyAM0,115200 root=/dev/mtdblock1�
  $ exec -c "console=ttyAM0,115200 root=/dev/mtdblock1"


After the TS-Kernel is loaded, The login prompt is displayed. Type �root� at the login
After the TS-Kernel is loaded, The login prompt is displayed. Type 'root' at the login
prompt, without a password. A Bash shell login prompt will then appear. At this point, the
prompt, without a password. A Bash shell login prompt will then appear. At this point, the
TS-7250 is executing the run-time Technologic Systems Linux kernel and accepting user
TS-7250 is executing the run-time Technologic Systems Linux kernel and accepting user
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provide zero-cycle latency to the current program and data, or they can be locked to
provide zero-cycle latency to the current program and data, or they can be locked to
guarantee no-latency access to critical sections of instructions and data. For applications
guarantee no-latency access to critical sections of instructions and data. For applications
with instruction-memory size restrictions, the ARM920T�s compressed Thumb instruction
with instruction-memory size restrictions, the ARM920T's compressed Thumb instruction
set can be used to provide higher code density and lower Flash storage requirements.
set can be used to provide higher code density and lower Flash storage requirements.
[[Image:Cirrus-ep9302-block-diagram.jpg|600px]]
[[Image:Cirrus-ep9302-block-diagram.jpg|600px]]
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* 16 kbyte Instruction Cache with lockdown
* 16 kbyte Instruction Cache with lockdown
* 16 kbyte Data Cache (programmable write-through or write-back) with lockdown
* 16 kbyte Data Cache (programmable write-through or write-back) with lockdown
* MMU for Linux�, Microsoft� Windows� CE and other operating systems
* MMU for Linux®, Microsoft® Windows® CE and other operating systems
* Translation Look Aside Buffers with 64 Data and 64 Instruction Entries
* Translation Look Aside Buffers with 64 Data and 64 Instruction Entries
* Programmable Page Sizes of 1 Mbyte, 64 kbyte, 4 kbyte, and 1 kbyte
* Programmable Page Sizes of 1 Mbyte, 64 kbyte, 4 kbyte, and 1 kbyte
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The EP9302 interrupt controller also includes the following features:
The EP9302 interrupt controller also includes the following features:
* Supports 54 interrupts from a variety of sources (such as UARTs, GPIO and ADC)
* Supports 54 interrupts from a variety of sources (such as UARTs, GPIO and ADC)
* Routes interrupt sources to either the ARM920T�s IRQ or FIQ (Fast IRQ) inputs
* Routes interrupt sources to either the ARM920T's IRQ or FIQ (Fast IRQ) inputs
* Three dedicated off-chip interrupt lines operate as active high level sensitive interrupts
* Three dedicated off-chip interrupt lines operate as active high level sensitive interrupts
* Any of the 19 GPIO lines maybe configured to generate interrupts
* Any of the 19 GPIO lines maybe configured to generate interrupts
Line 635: Line 635:


{{Warning|Use only the Watchdog Timer implemented by Technologic Systems in the CPLD. The Watchdog Timer included in the EP9302 has serious problems.}}
{{Warning|Use only the Watchdog Timer implemented by Technologic Systems in the CPLD. The Watchdog Timer included in the EP9302 has serious problems.}}
= Common Interfaces General Information =
The purpose of this section is to provide general information about the common
interfaces, such as Serial Ports and Digital Input/Output, which appear in more than one
header or connector of the TS-7250. For further information on these features, refer to the
Connectors and Headers section of this manual.
== Serial Ports ==
The TS-7250 have two asynchronous serial ports (COM1 and COM2) which provide a
means to communicate with external serial devices. Each is independently configured as
a 16C550- type COM port that is functionally similar to a standard PC COM port. These
ports have 16-byte FIFOs in both the receive and the transmit UART channels. Both COM
ports can support all standard baud rates up through 230.4Kbaud. Both COM ports may
be configured to use a DMA channel (useful when very high baud rates are being used).
COM1 and COM2 UARTs can generate:
* Four individually maskable interrupts from the receive, transmit, and modem status logic blocks
* A single, combined interrupt that is asserted if any of the individual interrupts are asserted and unmasked
The COM1 port can also support the HDLC protocol. Refer to the Cirrus EP9301 User's
Guide for more details. The COM2 port can optionally support RS-485 half or full duplex
levels.
== Digital I/O ==
There are 20 Digital Input/Output (DIO) lines available on the TS-7250 . These are
available on two headers labeled "DIO" and "LCD". The header labeled LCD can be used
as 11 DIO lines or as an alphanumeric LCD interface. The header labeled DIO has 9 DIO
pins available. In addition to the DIO signals, each header also has a power pin and
Ground available. The LCD header has 5V power available while the DIO header has
3.3V power.
The DIO2 header (FPGA DIO) is controlled by the on-board FPGA. It is a 40-pin header
divided in two sub-headers of 20 pins each. On the first header, by default, there are 17
video signals that can be changed into digital I/O, while the second, labeled DIO2, has 18
digital I/O lines which implement two XDIO ports. Thus, there are 35 total DIO lines
connected directly to the on-board FPGA on the TS-7250 available through the 40-pin
header. The first header has 5V power available and the second (DIO2) has 3.3V power.
Three pins on the DIO header are used to bring out the EP9302 SPI bus. By using some
of the DIO pins as peripheral Chip Select signals, a complete interface is available for SPI
peripherals. It is also possible to bring out a fourth SPI bus function [SPI_Frame] by
adding a 10 ohm resistor in the position labeled R1 on TS-7250 boards. This signal is not
required for many SPI peripherals but it may prove useful in some applications.
All of the DIO lines are programmable as either inputs or outputs and the direction of each
I/O pin can be individually programmed. All DIO control registers are 8-bits wide and
aligned on word (32-bit) boundaries. For all registers, the upper 24 bits are not modified
when written and are always read back as zeros. Every DIO pin has two registers used to
access it, an 8-bit data register and an 8-bit data direction register (DDR). The DDR
controls whether each DIO pin is an input or an output ("1" = output). Writing to the data
register only affects pins that are configured as outputs. Reading the data register always
returns the state of the DIO pin.
Many of the DIO pins (DIO_0 thru DIO_8 and LCD_0 thru LCD_7) can also be
programmed to cause interrupts. The interrupt properties of these pins are individually
configurable. Each interrupt can be either high or low level sensitive or either rising or
falling edge triggered. It is also possible to enable debouncing on any of these interrupts.
Debouncing is implemented using a 2-bit shift register clocked by a 128 Hz clock. Refer to
the [[http://www.embeddedarm.com/documentation/third-party/ts-7000_ep9301-ug.pdf EP9301 User's Guide]] and see Chapter 21 for details
The 5V power output pin on the LCD Header is current limited to 1000mA to prevent
excessive current. The 3.3V power on the DIO1 Header is current limited to approximately
1 Amp by a 3.3V regulator.
== A/D Converters ==
The EP9302 A/D converter is standard on all TS-7250 boards. The Cirrus EP9302
features a 5 channel, 12-bit Analog to Digital Converter with an analog multiplexor, with an
input range of 0 to 3.3 V.
On the TS-7200, only the top and bottom channels (ADC0 and ADC4) are brought out on
the DIO1 Header. On the TS-7250, the dedicated A/D Header brings out all the 5 EP9302
A/D channels. The TS-7260 uses 3 of the 5 EP9302 A/D channels for on-board
measurements, therefore only 2 channels are available on the DIO2 Header.
The TS-7200 and TS-7250 support an optional 8 channel, 12-bit A/D converter (ADC) with
a conversion time of 12 uS through the MAX 197 chip. This will allow up to 60,000
samples per second. The dedicated MAX197 A/D Header brings out all the 8 A/D
channels.
= Connectors and Headers =
== 10/100 Base-T Ethernet Connector ==
The EP9302 Ethernet LAN controller incorporates all the logic needed to interface directly
to any MII compatible Ethernet PHY chip. A low-power Micrel KS8721 chip is used to
implement the Ethernet PHY function and an integrated RJ-45 connector with built-in
10/100 transformer and LED indicators completes the Ethernet sub-system.
The TS-7250 has both a LINK/ACTIVITY LED and a 10/100 speed LED built into each RJ-
45 connector that indicates the current Ethernet status. The LINK LED (left side of
connector, green) is active when a valid Ethernet link is detected. This LED should be ON
whenever the TS-7250 is powered and properly connected to a 10/100BaseT Ethernet
network. The LINK/ACTIVITY LED will blink to indicate network activity for either inbound
or outbound data. The SPEED LED (right side of connector, amber) will be on when a
100Mb network is detected and off for a 10Mb network. Both of these LEDs are controlled
by the KS8721 and do not require any overhead by the processor.
The Ethernet PHY chip can be powered down, under software control, to save
approximately 90 mA of current consumption. This is controlled by the EP9302 Digital
output on Port H, bit 2. A logic zero will power down the KS8721 PHY interface.
{{note|TS-Linux provides all the software support to use the EP9302 10/100 Ethernet core. For more details, find the TCP/IP configuration instructions on the TS-Linux documentation.}}
== USB Connector ==
The USB Connector on the TS-7250 provide two USB interfaces for the user. These are
directly connected to the EP9302 processor, which integrates an USB dual-port Open
Host Controller Interface (Open HCI), providing full-speed serial communications ports at
a baud rate of 12 Mbits/sec. Up to 127 USB devices (printer, mouse, camera, keyboard,
etc.) and USB hubs can be connected to the USB host in the USB "tiered-star" topology.
This includes the following features:
* USB 2.0 compatible
* Open HCI Rev 1.0 compliant
* USB device connections support at both low-speed (1.5 Mbps) and full-speed (12 Mbps)
* Root HUB integrated with 2 downstream USB ports
* Transceiver buffers integrated, over-current protection on ports
* Supports power management
* Operates as a master on the bus
{{note|TS-Kernel implements all the necessary driver support to enable the USB OHCI.  Also, a wide variety of USB drivers for devices such as mouse, keyboard and flash memory are available. Refer to the Linux for TS-ARM User's Guide or contact us for further information on how to integrate an USB device and an USB Linux driver with your TS-7250.}}
== COM1 Connector ==
The COM1 RS-232 port uses a DB-9 male connector on the TS-7250.
{|class="wikitable"
|+ Table: COM1 DB9 Pin-Outs
|-
! DB9 Pin !! Signal !! Description
|-
| 1 || DCD || Data Carrier Detect
|-
| 2 || RXD || Receive Data
|-
| 3 || TXD || Transmit Data
|-
| 4 || DTR || Data Terminal Ready
|-
| 5 || GND || Ground
|-
| 6 || DSR || Data Set Ready
|-
| 7 || RTS || Request to Send
|-
| 8 || CTS || Clear to Send
|-
| 9 || -- || --
|}
The base address of COM1 appears in the physical address space at '''0x808C_0000'''.
Technologic Systems provides software drivers to access this port. This full complement
of RS-232 signals (all except Ring Detect) allows COM1 to interface to almost any serial
RS-232 device.
==COM2 Header==
The base address of COM2 appears in the physical address space at '''0x808D_0000'''. Technologic Systems provides software drivers to access this port. COM2 has RS-232 support only for the TXD and RXD signals. This is sufficient to interface with serial devices that only require transmit and receive data lines. COM2 is accessible on a 10-pin header labeled COM2.
{| class="wikitable"
|-
| TX-
| NC
| NC
| RX-
| NC
|-
| 6
| 7
| 8
| 9
| 10
|-
| 1
| 2
| 3
| 4
| 5
|-
| TX+
| RXD
| TXD
| RX+
| GND
|}
{{note|The COM2 serial port header uses a non-standard numbering scheme.  This was done so the header pins would have the same numbering as the corresponding DB-9 pin; i.e. pin 3 (TXD) on the header connects to pin 3 on the DB-9.}}
{| class="wikitable"
|-
! COM2 Header
! DB9 Connector
! RS-232
! Half Duplex RS-485
! Full Duplex RS-485
|-
| 1
| 1
|
| TX+ / RX+
| TX+
|-
| 2
| 2
| RXD
|
|
|-
| 3
| 3
| TXD
|
|
|-
| 4
| 7
|
|
| RX+
|-
| 5
| 5
| GND
| GND
| GND
|-
| 6
| 6
|
| TX+ / RX+
| TX-
|-
| 7
| 7
|
|
|
|-
| 8
| 8
|
|
|
|-
| 9
| 9
|
|
| RX-
|-
| 10
| --
| --
| --
| --
|}
Adapter cables are available to convert COM2 to a standard 9-pin SubD male connector. In addition, COM2 has optional support for full or half-duplex RS-485
{{note|The COM2 serial port 10-pin header has both RS-232 and RS-485 signals. Only one set may be used for a given application - it is not possible to use both at the same time.}}
====Optional RS-485 Support====
The COM2 Port supports RS-485 half duplex or full duplex operation. RS-485 drivers allow communications between multiple nodes up to 4000 feet (1200 meters) via twisted pair cable. Half-duplex RS-485 requires one twisted pair plus a Ground connection, while full duplex requires two twisted pair plus a Ground. For half-duplex operation, a single twisted pair is used for transmitting and receiving.
The ioctl Linux system call is used to initialize the automatic RS-485 control logic. For full-duplex operation, two twisted pairs are used and the transmit driver is typically enabled all the time. Fail-safe bias resistors are used to bias the TX+, TX- and RX+, RX- lines to the correct state when these lines are not being actively driven. In a typical RS-485 installation, the RS-485 drivers are frequently "tri-stated." If fail-safe bias resistors are not present, the RS-485 bus may "float" and small amounts of noise can cause spurious characters at the receivers. 4.7K Ohm resistors are used to pull the TX+ and RX+ signals to 5V and also to bias the TX- and RX- signals to ground.
Termination resistors in many installations are not required when cable lengths are less than 50 meters and the baud rate is 9600 or less. Termination resistors may be required for reliable operation when running longer distances or at higher baud rates. Termination resistors (typically 100-150 ohms) should only be installed at each end of an RS-485 transmission line. In a multi-drop application where there are several drivers and/or receivers attached, only the devices at each end of the transmission line pair should have termination resistors.
A read at I/O location '''0x2240_0000''' bit 1 will return a "1" when the RS-485 option is installed.
{{note|A special ioctl command has been added to the TS-Kernel's serial code to turn off and on the automatic RS-485 feature. Refer to the Linux for TS-ARM User's Guide for additional software information on RS-485 support.}}
====RS-485 Quick-Start Procedure====
Perform the following steps:
# Check that the RS-485 option is installed in the TS-7250 (required).
# Attach the RS-485 cable to the 10-pin header. (Adapter cables to SubDB9 connector are available from Technologic Systems).
# Set the COM2 UART serial parameters (baud rate, data, parity, and stop bits, interrupts, etc) in your source code.
# Use the TIOC_SBC's485 ioctl() to enable the automatic RS-485 feature.
# Simply read() and write() data to the COM2 UART - the automatic RS-485 logic controls TX enable.
====Automatic RS-485 TX Enable====
The TS-7250 supports fully automatic TX enable control under hardware control. This simplifies the design of half-duplex systems since turning off the transmitter and enabling the receiver in software is typically difficult to implement. If this is implemented in software, then the COM2 UART transmit holding register and the transmit shift register both must be polled until empty before deasserting the TX enable signal to the RS-485 driver. The design gets more complicated when using the TX FIFO or when using a multi-tasking OS such as Linux.
The implementation on the TS-7250 uses hardware to automatically control when the RS-485 drivers and receivers are selected. The automatic RS-485 logic eliminates the need for any software polling and supervision. This circuit automatically turns on/off the RS-485 transceiver and receiver at the correct times. This only requires the COM2 Mode registers to be initialized once based on baud rate and data format.
{| class="wikitable"
|-
! Value
! MSB
! MID
! LSB
! Mode
|-
| 0x00
| 0
| 0
| 0
| RS-232
|-
| 0x01
| 0
| 0
| 1
| Full-Duplex RS-485
|-
| 0x02
| 0
| 1
| 0
| -- Reserved
|-
| 0x03
| 0
| 1
| 1
| -- Reserved
|-
| 0x04
| 1
| 0
| 0
| Half-Duplex 9600 Baud
|-
| 0x05
| 1
| 0
| 1
| Half-Duplex 19.2Kbaud
|-
| 0x06
| 1
| 1
| 0
| Half-Duplex 57.6Kbaud
|-
| 0x07
| 1
| 1
| 1
| Half-Duplex 115.2Kbaud
|}
COM2 will default to RS-232 mode at reset (COM2 mode register = Hex 00). In order to switch COM2 into Full duplex RS-485 mode, the COM2 Mode register at 0x22C0_0000 must be set to Hex 01. In this mode, the TX drivers are always asserted.
In order to switch COM2 into half-duplex RS-485, then the COM2 mode register at 0x22C0_0000 must be set to Hex 04, 05, 06 or 07 depending upon the baud rate required. A second COM2 Mode register at 0x2300_0000 must be set to Hex 01 if the COM2 is in half-duplex mode and the data format is using 8 data bits with parity or 8 data bits with 2 stop bits.
{{note|COM2 in half-duplex RS-485 supports baud rates of 9600, 19.2K, 57.6K and 115.2K. If you need to operate at any other baud rate, then please contact Technologic Systems.}}
==DIO1 Header==
The DIO1 Header provides +3.3V, GND, and 9 digital I/O lines that may be used to interface the TS-7250 with a wide range of external devices. DIO lines DIO_0 thru DIO_7 are a byte-wide port using Port B on the EP9302 and are accessed via the data register at address location '''0x8084_0004'''. The DDR for this port is at address location '''0x8084_0014'''.
{| class="wikitable"
|-
! DIO1 Pin
! Default Signal
! TS-7200
|-
| 1
| DIO_0
|
|-
| 2
| GND
|
|-
| 3
| DIO_1
|
|-
| 4
| Port_C0
| ADC0
|-
| 5
| DIO_2
|
|-
| 6
| SPI_Frame
| ADC4
|-
| 7
| DIO_3
|
|-
| 8
| DIO_8
| ADC4
|-
| 9
| DIO_4
|
|-
| 10
| SPI_MISO
|
|-
| 11
| DIO_5
|
|-
| 12
| SPI_MOSI
|
|-
| 13
| DIO_6
|
|-
| 14
| SPI_CLK
|
|-
| 15
| DIO_7
|
|-
| 16
| +3.3V
|
|}
DIO_8 is accessed via bit 1 of Port F in the EP9302. The Port F data register is at address location '''0x8084_0030'''. The DDR address for this port is location '''0x8084_0034'''.
The Pin 4 of the DIO1 Header, in the default configuration, is accessed via bit 0 of Port C in the EP9302. The address location '''0x8084_0008''' is Port C Data Register and '''0x8084_0018''' is Port C Directon Register.
When accessing these registers, it is important not to change the other bit positions in these Port F registers. Other DIO1 Port functionality, used for dedicated TS-7250 functions, utilize these same control registers. All accesses to these registers should use read-modify-write cycles.
{{Warning|All pins on the DIO header use 0-3.3V logic levels. Do not drive these lines to 5V.}}
When the DIO pins are configured as outputs, they can "source" 4 mA or "sink" 8 mA and have logic swings between GND and 3.3V. When configured as inputs, they have standard TTL level thresholds and must not be driven below 0 Volts or above 3.3 Volts. DIO lines DIO_0 thru DIO_3 have 4.7K Ohm "pull-up" resistors to 3.3V biasing these signals to a logic"1". The other DIO pins have 100K Ohm bias resistors biasing these inputs to a logic "1".
===SPI Interface===
The EP9302 Synchronous Serial Port is available on the DIO1 header. This port can implement either a master or slave interface to peripheral devices that have either Motorola SPI, or National Semiconductor Microwire serial interfaces.
The transmit and receive data paths are buffered with internal FIFO memories allowing up to eight 16-bit values to be stored for both transmit and receive modes. The clock rate is programmable up to 3.7 MHz and has programmable phase and polarity. The data frame size is programmable from 4 to 16 bits.
By using some of the DIO1 Header pins as peripheral Chip Select signals, a complete interface is available for addressing up to 9 SPI peripherals. The SPI bus pins are defined in the table below:
{| class="wikitable"
|-
! DIO1 Pin
! Name
! Function
|-
| 10
| SPI_MISO
| Master In/Slave Out
|-
| 12
| SPI_MOSI
| Master Out/Slave In
|-
| 14
| SPI_CLK
| Clock
|-
| 6
| SPI_Frame
| SPI Frame pin
|}
A fourth SPI bus function [SPI_Frame] is available by adding a 10 ohm resistor in the position labeled R1 on TS-7300. This signal is not required for many SPI peripherals but it may prove useful in some applications.
{{Warning|The SPI bus pins use 0-3.3V logic levels. Do not drive these lines to 5V.}}
Refer to the [http://www.embeddedarm.com/documentation/third-party/ts-7000_ep9301-ug.pdf EP9301 User's Guide] and see Chapter 19 for more details on using SPI bus.
===Matrix Keypad===
DIO signals DIO_0 thru DIO_7 are physically arranged to allow a 16-pin (2x8) ribbon cable to directly connect a '''4x4 matrix keypad'''. Sample code is available for the Matrix Keypad. Contact Technologic Systems for further information.
== A/D Header - Cirrus EP9302 ==
The EP9302 A/D converter can do a maximum of 925 samples per second, and requires a
settling time of 2 milliseconds between channel switches. Note that the Cirrus A/D
converter is not the same as the optional, full-featured MAX197 A/D converter. To
maintain 12-bit accuracy, the analog signal being measured must have a low source
impedance (less than 10 ohms). Otherwise, an operational amplifier may need to be
added to buffer the A/D input. The EP9302 A/D converter should not be driven by a
source impedance greater than 10 ohms to ensure accurate results (the EP9302 A/D
converter has an input impedance that is not completely linear and may be as low as 10K
ohms). For detailed information, please see the Cirrus EP9301 User's Guide, page 518.
For high-performance applications, the optional MAX197 A/D converter is preferred.
{|class="wikitable"
|+ Table: ADC Switch Values (EP9302)
|-
! Input to Measure !! ADC Switch Value
|-
| ADC0 || 0x0000_0608
|-
| ADC1 || 0x0000_0680
|-
| ADC2 || 0x0000_0640
|-
| ADC3 || 0x0000_0620
|-
| ADC4 || 0x0000_0610
|}
{|class="wikitable"
|+ Table: A/D Header Pin Out (EP9302)
|-
! GND !! GND !! GND !! GND !! GND
|-
| 2 || 4 || 6 || 8 || 10
|-
| 1 || 3 || 5 || 7 || 9
|-
! ch0 !! ch1 !! ch2 !! ch3 !! ch4
|}
The following steps outline the software execution to use the Cirrus A/D converter:
# Unlock the software lock before setting the TSEN bit in the ADCClk register by writing 0xAA to the ADCSWLock register (0x8090_00C0). "OR" in the TSEN bit (bit 31) to the ADCClkDiv register (0x8093_0090)
# Unlock the software lock (again) before OR'ing in the ADCEN (ADC clock enable, bit 31) to 0x8093_0080
# Clear bit 2, the ADCPD (ADC Power Down) bit, at 0x8093_0080. This bit MUST be set to 0 (see page 91 of the EP9301 User's Guide)
# After unlocking the software lock, write the channel's magic value (see Cirrus EP9301 User's Guide, table 20-2) to the ADCSwitch register (0x8090_0018) to select that channel for the next data acquisition
# Poll the ADCResult register (0x8090_0008) until bit 31 is not set
# Using a 32 bit read operation, read the result from 0x8090_0008, masking off the upper 16 bits
=== Interpreting Cirrus A/D Converter ===
The Cirrus on-chip A/D converter is a successive approximation A/D converter. Each A/D
channel is calibrated on the TS-7250 and these 16-bit values are stored in non-volatile
EEPROM. These calibration values minimize the offset errors and gain errors in the
EP9302 A/D. It is important for the user program to use these values as per our sample
code, which can be found either on our website or in the CD included in the Developer's
Kit. Two reference points, 0 and 2.5 Volts, with the corresponding reference values stored
in EEPROM. Bytes 0x07EB through 0x07FE of the EEPROM hold a two dimensional
array:
[channel number][0V ref. point, 2.5V ref. Point]
The reference points are stored as a 16 bit value, and should be used to correlate the values returned by the Cirrus A/D converter to voltage.
== A/D Header - Optional MAX197 ==
The TS-7250 supports an optional eight-channel, 12-bit A/D converter (ADC) with a
conversion time of 12 uS. This will allow up to 60,000 samples per second. Each channel
is independently software programmable for a variety of analog input ranges: -10V to
+10V, -5V to +5V, 0V to +10V, or 0V to +5V. This allows an effective dynamic range of 14
bits.
{|class="wikitable"
|+ Table: A/D Registers (MAX197)
|-
! I/O Address !! Action
|-
| 0x10F0_0000 || Write Initiate A/D Conversion
|-
| 0x10F0_0000 || Read LSB of Conversion
|-
| 0x10F0_0001 || Read MSB of Conversion
|-
| 0x2240_0000 || Read Bit 0 = 1 if A/D option installed
|-
| 0x1080_0000 || Read Bit 7 = 0 when Conversion completed
|}
Each channel is overvoltage tolerant from -16V to + 16V, and a fault condition on any
channel will not affect the conversion result of the selected channel. This is all
accomplished with a 5V only power supply; no negative supply voltage is required. The
Maxim MAX197 chip can be replaced with a MAX199 chip if a lower range of analog input
levels is required (-4V to +4V, -2V to +2V, 0V to 4V, and 0V to 2V).
{|class="wikitable"
|+ A/D Control Register (0x10F0_0000 Write)
|-
! Bit !! Description !! Details
|-
| 0-2 || Analog channel select || Channels 0-7
|-
| 3 || Unipolar / Bipolar || 0 = Unipolar (i.e. 0 to +5V)<br/>1 = Bipolar (i.e. -5V to +5V)
|-
| 4 || Range select || 0 = 5V range<br/>1 = 10V range
|-
| 5-7 || Mode bits || Set to 0, 1, 0
|}
A read at I/O location 0x2240_0000 bit 0 returns a "1" when the A/D option is installed on
the TS-7250.
=== Single Sample Acquisition Procedure ===
An acquisition is initiated by writing to I/O location 0x10F0_0000. The value written to this
location determines the channel to convert (bits 0-2) and selects one of four input ranges
(bits 3 and 4). Bits 5, 6, and 7 should be set to 0, 1, 0 respectively. After the write cycle to
location 0x10F0_0000, the MAX197 completes the A/D conversion in about 12 mS. Bit 7
at I/O location 0x2240_0000 may be polled to determine when the conversion is complete
(zero = complete). The conversion result is now available at locations 0x10F0_0000 (LSB)
and 0x10F0_0001 (MSB). A single word read at 0x10F0_0000 can also be used. When
using unipolar modes, the result is in binary format with the upper 4 bits of the MSB equal
to zero. When a bipolar mode is used, the result is in twos-complement binary with the
upper 4 bits (Bits 12-15) equal to bit 11 (sign extended).
{|class="wikitable"
|+ Table: A/D Header Pin Out (MAX197)
|-
! GND !! GND !! GND !! GND !! GND !! GND !! GND !! GND
|-
| 2 || 4 || 6 || 8 || 10 || 12 || 14 || 16
|-
| 1 || 3 || 5 || 7 || 9 || 11 || 13 || 15
|-
! ch0 !! ch1 !! ch2 !! ch3 !! ch4 !! ch5 !! ch6 !! ch7
|}
If more details on the A/D converter specifications are required, go to the Maxim web site
and search for MAX197.




Revision as of 22:17, 30 April 2012

TS-7250
TS-7250.jpg
Product Page
Documentation
Schematic
Mechanical Drawing
FTP Path
Cirrus Logic EP9302
CPU User Guide

Introduction

About this Manual

This manual is intended to provide the user with an overview of the board and benefits, complete features specifications, and set up procedures. It contains important safety information as well.

TS-72XX Series

The TS-72XX series Single Board Computers (SBC's) run on a 200 MHz ARM9 processor with power as low as 1/2 Watt. Low board complexity, low component count, and low power/heat makes for an extremely reliable embedded engine. The TS-72XX SBC's are available in thousands of configurations, many of which are Commercial off the Shelf (COTS) and available to ship today.

The EP9302 processor from Cirrus is the highly integrated 200Mhz ARM9 processor that the TS-72XX SBC's are built around and includes an on-chip 10/100 ethernet, USB, serial, and Flash/SDRAM controller. For example, on the TS-7200 model there is 32 Mb of Micron SDRAM running at 66 Mhz and 8 Mb Intel Strata flash on-board. A supplemental PLD provides glue logic, watchdog timer, Compact Flash IDE, and 8 bit PC/104 support. Integer CPU performance is about 20% faster than our 133 Mhz x86 offerings. Even with the standard power consumption of 2 Watts, the TS-72XX SBC's run without fans or heat sinks in the temperature range of -20 to +70°C. Extended Temperature -40° to +85°C is also standard, but CPU clock must be decreased to about 166MHz for higher temperatures. Digital Signal Processing (DSP) is enabled through a standard 5 channel, 12bit A/D converter (Optional 8 channel, 12 bit A/D converter), 20 DIO lines and 2 standard serial ports.

The 8/16 bit PC/104 interface enables additional functionality through Technologic Systems' broad product line of PC/104 peripheral daughter boards. The TS-7KV adds video, CAN, Com Ports, and A/D conversion. The TS-ETH10 allows the addition of Ethernet ports. The TS-CAN adds CAN connectivity. The TS-Modem boards add both wired and cell phone capabilities.

The TS-72XX rugged ARM9 SBC's have found their way into many embedded applications. Customers are using the TS-72XX series SBC's in: energy generation, manufacturing process control, traffic management, printing system management, communication infrastructure, website hosting, data gathering and laboratory test equipment. We use a TS-7200 to host our complete website and to prepare and test your SBC prior to shipping.

Product Overview

The TS-7250 is a compact, full-featured Single Board Computer (SBC) based upon the Cirrus EP9302 ARM9 CPU. The EP9302 features an advanced 200 MHz ARM920T processor design with a memory management unit (MMU) that allows support for high level operating systems such as Linux, Windows CE, and other. As a general-purpose processor, it provides a standard set of peripherals on board and a full set of Technologic Systems featured peripherals via the standard PC/104 Bus.

Benefits

Out-of-the-Box Productivity Technologic Systems Linux products get you to your application quickly. Our Single Board Computers boot directly to Linux as shipped. There is no complicated CMOS setup or configuring of a Linux derivative Operating System to source, define, and load. Technologic Systems has pre-configured each SBC in flash memory.

The TS-7250's user can power up the board and immediately begin application development. Of course, should you wish to configure your own version of Linux or use a different operating system, this is easy too. Technologic Systems provides the solution to fast application development without tedious OS configuration.

Impressive Performance The ARM920T's 32-bit architecture, with a five-stage pipeline, delivers very impressive performance at very low power. The EP9302 CPU has a 16 KB instruction cache and a 16 KB data cache to provide zero-cycle latency to the current program and data, or they can be locked to guarantee no-latency access to critical sections of instructions and data. For applications with instruction-memory size restrictions, the ARM920T's compressed Thumb instruction set can be used to provide higher code density and lower Flash storage requirements.

As a benchmark, the TS-7250's CPU integer performance, at a supplied 200 MHz, is about twice as fast as the Technologic Systems 133MHz 586-based products.

Features

The TS-7250 comes standard with these features:

  • TS-Linux Embedded Operating System Installed
  • 200 MHz ARM9 CPU with MMU
  • 32 MB on-board NAND Flash (Boots to TS-Linux)
  • 32 MB RAM
  • 2 USB 2.0 Compatible OHCI ports (12 Mbit/s Max)
  • 2 serial ports (up to 230 Kbaud)
  • 10/100 Megabit Ethernet port
  • 20 total Digital I/O lines
  • 5 channel 12-bit A/D converter
  • Watchdog Timer
  • PC/104 expansion bus
  • SPI bus interface
  • Alphanumeric LCD and Matrix keypad interfaces
  • Single +5VDC power supply @ 450 mA
  • Small size 3.8 x 4.5 inches (9.7 x 11.5 cm)
  • Operating Temperature Range: Fanless from -20° to +70°C
  • Extended Temperature -40° to +85°C standard at lower CPU clock speeds (166MHz)

Configurability

The TS-7250 can be configured for your application using the following available on-board options and external accessories:

On-board Options

  • TS-7xxx-yyy-zzzF: up to 'yyy' MB of on-board SDRAM and 'zzz' MB of Flash memory

upgrade for TS-7xxx board models. For example, TS-7250-64-128F selects model TS- 7250 upgrade with 64 MB of SDRAM and 128 of NAND Flash.

Model (xxx) SDRAM (yyy) on-board Flash (zzz)
TS-7200 Up to 64 MB Up to 16 MB
TS-7250 up to 64-128 MB Up to 64-128-256 MB
TS-7260 up to 64-128 MB Up to 64-128-256 MB
  • OP-ADC: 12 bit 8 channel A/D Converter (TS-7200 and TS-7250)
  • OP-2TTLCOM: Two additional COM (COM4 and COM5) ports with TTL levels (TS- 7260)
  • OP-SDSOCKET: One SD Card socket for additional flash memory (TS-7260)
  • OP-BBRTC: on-board sealed-battery backed RTC
  • OP-TMPSENSE: High-precision temperature sensor
  • OP-485-FD: RS-485 full duplex interface on COM2
  • OP-485-HD: RS-485 half duplex interface on COM2
  • OP-16BIT-104: 16-bit PC/104 Connector
  • OP-STHRU-104: 16-bit Pass-Thru PC/104 Connector
  • OP-ROHS: RoHS directive compliant built board
Note: The TS-7250 SBC can be built compliant with the RoHS (Restriction of Hazardous Substances ) Directive. Contact Technologic Systems for RoHS support.

External Accessories

  • CF-512-LIN: 512 MB Compact Flash Card with full ARM tool chain and Debian installed (TS-7200)
  • SD-256: 256 MB SD Flash Card with full ARM tool chain installed and Debian (TS-7260)
  • SD-512: 512 MB SD Flash Card with USB Interface, full ARM tool chain installed and Debian (TS-7260)
  • USB Flash Drive: 256 MB with full ARM tool chain installed and Debian
  • OP-EJECT: Compact Flash Ejector (TS-7200)
  • WIFI-G-USB: Linux-supported USB 802.11g WiFi transceiver for wireless networking
  • OP-LCD-LED: Alphanumeric 2x24 LCD with back light and cable
  • OP-KPAD: Matrix keypad with cable
  • PS-5VDC-REG: Regulated 5VDC Power Supply, 110 VAC Input
  • TS-ENC720: Metal Enclosure with Power Converter
  • RC-DB9: COM2 adapter cable to DB-9

In addition, a complete set of interfacing cables, connectors, and enclosures is available.

Note: Check our website at www.embeddedARM.com for an updated list of options and external accessories

PC/104 Peripherals

Technologic Systems offers many add-on peripherals to complete the requirements of your application. These products directly interface with the TS-7250 using the PC/104 bus, adding a wide variety of functionalities at very reasonable prices. Some of these functionalities includes:

  • NVRAM - adds 32K, 128K, 1MB or 2MB bytes of battery-backed SRAM. Battery backed SRAM provides non-volatile memory with very fast write times and unlimited write cycles, unlike Flash memory. This can be very important if the data is constantly being updated several times per minute, since Flash devices can wear-out after a few million write cycles. It also eliminates the latency that Flash memory has during write cycles. This resource is a byte-wide memory device using a lithium battery that will last a minimum of 10 years with or without power applied.
  • Analog VIDEO interface - When a video monitor is needed.
  • CAN Bus - Useful for automotive applications.
  • Modems - Phone Line or GSM Cellular modems.
  • Additional Ethernet ports.
  • Additional DIO interface with either 24 or 64 new lines..
  • Additional 12 bit ADC and DAC: useful for industrial automation applications.
  • Additional COM and Parallel ports - Make more communication channels available.
  • Power-over-Ethernet
  • Radios - Long-range wireless radios, Xbee modules
Note: New PC/104 boards are always in development. Contact Technologic Systems or visit the PC/104 peripherals page at our website for a complete and updated list of additional functionalities that can be added to the TS-7250 using the PC/104 bus. You can also contact Technologic Systems about your custom project design.

TS-ARM Development Kit

The TS-ARM Development Kit for the TS-7250 Single Board Computer includes all equipment necessary to boot into the operating system of choice and start working. The development kit is highly recommended for a quick start on application development. The TS-ARM Development Kit contains a 256 or 512 MB Flash drive (Compact Flash for 7200, USB for 7250 and 7260) which includes:

Kit-arm.gif

  • a self-hosting ARM installation of the Debian Linux 2.0 distribution compiled for ARM
  • gcc 2.95.4 and gcc 3.0 compiler with full tool-chain
  • Build tools and source for JFFS/YAFFS file system in on-board NAND Flash.
  • Hardware test routines source code and other example source code
  • Debian package system: apt-get, tasksel, dselect The development kit additionally includes:
  • USB Compact Flash reader for TS-7200
  • 5 VDC regulated power supply (international versions available)
  • NULL modem cable
  • Adapter cable from 10-pin header to DB9
  • Various cables for connection DIO, LCD, Keypad, etc.
  • Development CD with complete TS-Kernel source, manuals, example code, etc.
  • Printed supporting documentation for TS-72XX's Hardware, Linux for ARM and Development Kit.
Note: Single Board Computer is not included on the Development Kit (sold separately).

Software and Support

Technologic Systems provides:

  • Free system software and documentation updates available on our web site
  • Free technical support by phone, fax, or email
  • 30-day, money back guarantee on evaluation units
  • One-year, full warranty

Linux OS Support

The ARM processor (the EP9302) comes from Cirrus and the platform is very similar to the Cirrus EDB9302 evaluation board. Cirrus has strongly promoted running Linux on this chip and has done most of the legwork in creating a patch set to the Linux 2.4 kernels, but we have also had to modify the Linux Kernel (TS-Kernel) so it can support the 8MB onboard Flash chip (via mtd drivers), the compact flash IDE driver, and the A/D converter. If you want to use Linux and aren't tied to the x86 architecture, the TS-72XX boards can be very cost-effective.

The TS-72XX SBC's are shipped standard with the compact TS-Linux embedded operating system installed in the on-board Flash memory. The fullfeatured Debian Linux can also be used with an NFS root file system or larger Flash drives, such as Compact Flash cards, SD cards and USB flash drives. The TS-Kernel used is based upon the version 2.4.26, patched and compiled for the Cirrus EP9302 ARM920T processor, and is real-time capable through RTAI.

The root file system used by the Linux OS can be any of the following:

  • JFFS/YAFFS file system image in the on-board Flash (if using RedBoot, it should include the option root=/dev/mtdblock1 to instruct the kernel to boot here)
  • EXT2 file system image in the Compact Flash card (if using RedBoot, it should include the option root=/dev/hda)
  • NFS root, via Ethernet port (if using RedBoot, it should include the option root=/dev/nfs nfsroot=<IP>:<DIRECTORY> ip=dhcp)
Note: The TS-Kernel supports the Real-Time Application Interface (RTAI project), making the embedded operating system capable of handling applications with hard real-time restrictions.

Other OS Support

The TS-7250 can be loaded with other operating systems such as Windows CE, NetBSD, etc. Technologic Systems will provide support for these, and possibly other operating systems, in the future. Currently, only Linux and NetBSD are supported on the TS-7250.

Getting Started

Installation Procedure

Before performing any set up or placement procedures, take the precautions outlined in this section.

Handling the Board Safely

Be sure to take appropriate Electrostatic Discharge (ESD) precautions. Disconnect the power source before moving, cabling, or performing any set up procedures.

WARNING: Inappropriate handling may cause damage to the board.

Setup and Installation Instructions

Follow these guidelines for safety and maximum product performance:

  • Observe local health and safety requirements and guidelines for manual material

handling

Setup Tools

Depending on placement and cabling, you may need the following tools:

  • Small flat-blade screwdriver
  • Small Phillips screwdriver

Setup Procedure

After locating, setting up, grounding, and cabling the TS-7250:

  • Apply power
  • Monitor the TS-7250 using a terminal emulator to verify that the board is operating properly
Note: Your board might include a screw power connector on the power input. Notice this connector is removible. Please pull this connectior off before applying power.

Disconnecting AC Power

  • Unplug from the power source.
  • Disconnect other cables as required.

Console and Power Up

The TS-72XX SBC's have no video controller or keyboard interface. This was done to keep the board size small and the cost low. COM1 is typically used as a console port to interface the TS-72XX to a standard terminal emulation program on a Host PC. An ANSI terminal or a PC running a terminal emulator is required to communicate with your Embedded PC. Simply connect an ANSI terminal (or emulator) to COM1 (DB9 female connector) using a null modem cable (this is included in the TS-ARM Development Kit), using serial parameters of 115,200 baud, 8 data bits, no parity, no flow control, 1 stop bit, and make sure jumper JP2 is installed. If you are running Linux, the minicom program works well, Windows users can run the Hyperterm application. Technologic Systems offers a null modem cable with both 25 pin and 9 pin connectors at each end as part number CB7-05. Some systems also require the 10-pin header to 9-pin Sub-D adapter which is P/N: RC-DB9.

The console can be changed to COM2 by installing JP4 (with JP2 also installed). If your application does not require a console or both COM ports are required, then removing the jumper JP2 easily disables all console output. Connect a regulated 5VDC, (1A minimum) power source using the included 2 screw terminal strip/connector. Please note the polarity printed on the board. The boot messages, by default, are all displayed on COM1 at 115200 baud.

Boot Sequence

The boot sequence has four distinct stages:

  1. TS-BOOTROM messages
  2. RedBoot ROM monitor messages
  3. Linux Kernel messages
  4. Login prompts

Upon power up, the board executes proprietary Technologic Systems boot-code, TSBOOTROM, then immediately executes RedBoot. RedBoot is a feature rich boot-ROM monitor, that allows manipulation of the on-board flash, JFFS2/YAFFS2 images, loading and execution of a kernel or executable from either tftp (trivial ftp), serial console, or from flash, and offers GDB debugging stubs.

If not interrupted by the user within one second, a pre-existing RedBoot script is executed, loading a default Linux kernel into memory from on-board flash. This will cause the preexisting JFFS2/YAFFS2 file-system to boot.

One can view the RedBoot defaults for the board, as well as the default script, by entering at the RedBoot command prompt: 

$ fconfig -l

The defaults can be changed by simply entering 'fconfig' at the RedBoot prompt and answering the prompts. A final chance to write or discard the changes to the board will be given by RedBoot.

The default script instructs RedBoot to load the Linux kernel from the flash, and instruct the Linux kernel to use the JFFS2/YAFFS2 image on the flash chip for its root file-system. The Linux kernel must be loaded into memory address 0x00218000. Loading the kernel from flash is done automatically by RedBoot in the default script with the following command: 

$ fis load vlinux

After loading the kernel, the default script then executes the kernel with the following command: 

$ exec -c "console=ttyAM0,115200 root=/dev/mtdblock1"

After the TS-Kernel is loaded, The login prompt is displayed. Type 'root' at the login prompt, without a password. A Bash shell login prompt will then appear. At this point, the TS-7250 is executing the run-time Technologic Systems Linux kernel and accepting user commands.

Loading or Transferring Files

Three methods are available for transferring files between a desktop PC and your TS- 7250: Ethernet downloads, flash memory devices, and Zmodem downloads. Full descriptions of each are detailed below. Other programs that use serial ports to transfer should work as well.

Transferring Files via the Ethernet Port

The default JFFS Linux root file system includes a small FTP server that can be used for uploading/downloading of files across an Ethernet network. Simply point your preferred FTP client to your TS-7250 IP address (default is 192.168.0.50). You can login as root or any valid user previously created from the useradd utility. By default, the JFFS image will not accept anonymous FTP.

Transferring Files via Flash Memory Device

The TS-7250 removable Compact Flash card, an SD card or an USB flash memory card can be used to easily move files from a host system. We suggest using a low-cost SanDisk USB Compact Flash card or SD card interface for your host system. USB memory devices need no extra accessory to connect to the host PC. The flash memory devices can then be hot swapped (inserted or removed without rebooting the host PC).

Zmodem Downloads

Using the Zmodem protocol to send files to and from the TS-7250 SBC is simple and straightforward. The only requirement is a terminal emulation program that supports Zmodem, and virtually all do. If you are using Windows 95 or later for your development work, the HyperTerminal accessory works well. To download a file to the TS-7250 from your host PC, execute lrz at the Linux command line on the TS-7250 (while using console-redirection from within your terminal emulator) and begin the transfer with your terminal emulator. In HyperTerminal, this is 'Send File...' from the 'Transfer' menu. To upload a file from the TS-7250 to your host PC, execute lsz <FILENAME> at the Linux command line on the TS-7250 and start the transfer in your terminal emulator. Many emulators, HyperTerminal among them, will automatically begin the transfer themselves. Occasionally there may be errors in transmission due to background operations. This is not a problem -- Zmodem uses very accurate CRC checks to detect errors and simply resends bad data. Once the file transfer is complete the file is completely error free. For best results when using HyperTerminal, the hardware handshaking must be enabled in HyperTerminal.

Hardware Components

The following picture shows where the main headers, connectors and most important hardware components are located on the TS-7250. Understanding this picture will help you to follow the header-connector oriented organization of this manual. The blue marked objects on the picture are the on-board chips and components, while the red ones are the various on-board headers and connectors for peripherals.

Ts-7250-harware-components.png

Processor

Cirrus EP9302

The EP9302 features an advanced 200 MHz ARM920T processor design with a memory management unit (MMU) that allows support for high-level operating systems such as Linux, Windows CE, and other embedded operating systems. The ARM core operates from a 1.8 V supply, while the I/O operates at 3.3 V with power usage between 100 mW and 750 mW (dependent on speed). As a general-purpose processor, it provides a standard set of peripherals on board and a full set of Technologic Systems add-on peripherals via the standard PC/104 Bus.

The ARM920T's 32-bit architecture, with a five-stage pipeline, consisting of fetch, decode, execute, memory, and write stages, delivers very impressive performance at very low power. The EP9302 CPU has a 16 KB instruction cache and a 16 KB data cache to provide zero-cycle latency to the current program and data, or they can be locked to guarantee no-latency access to critical sections of instructions and data. For applications with instruction-memory size restrictions, the ARM920T's compressed Thumb instruction set can be used to provide higher code density and lower Flash storage requirements. Cirrus-ep9302-block-diagram.jpg

EP9302 key features include:

  • ARM (32-bit) and Thumb (16-bit compressed) instruction sets
  • 32-bit Advanced Micro-Controller Bus Architecture (AMBA)
  • 16 kbyte Instruction Cache with lockdown
  • 16 kbyte Data Cache (programmable write-through or write-back) with lockdown
  • MMU for Linux®, Microsoft® Windows® CE and other operating systems
  • Translation Look Aside Buffers with 64 Data and 64 Instruction Entries
  • Programmable Page Sizes of 1 Mbyte, 64 kbyte, 4 kbyte, and 1 kbyte
  • Independent lockdown of TLB Entries

For further information about the EP9302 features, refer to the EP9301 User's Guide.

Note: The EP9302 is identical silicon to the EP9301 except it is rated to run at 200 Mhz, instead of 166 Mhz. The available EP9301 User's Guide can still be used as the main reference manual.

MMU

The EP9031 features a Memory Management Unit, enabling high level operating systems such as Embedded Linux and Windows CE to run on the TS-7250. In the same way, the Linux TS-Kernel takes advantage of the MMU functionality. The MMU is controlled by page tables stored in system memory and is responsible for virtual address to physical address translation, memory protection through access permissions and domains, MMU cache and write buffer access. In doing so, software applications can access larger "virtual" memory space than the available physical memory size, allowing multiple programs to run and use the system memory simultaneously. For further information about the MMU functionalities, refer to the EP9301 User's Guide.

Interrupts

The EP9302 interrupt controller allows up to 54 interrupts to generate an Interrupt Request (IRQ) or Fast Interrupt Request (FIQ) signal to the processor core. Thirty-two hardware priority assignments are provided for assisting IRQ vectoring, and two levels are provided for FIQ vectoring. This allows time critical interrupts to be processed in the shortest time possible.

Internal interrupts may be programmed as active high or active low level sensitive inputs. GPIO pins programmed as interrupts may be programmed as active high level sensitive, active low level sensitive, rising edge triggered, falling edge triggered, or combined rising/falling edge triggered. The EP9302 interrupt controller also includes the following features:

  • Supports 54 interrupts from a variety of sources (such as UARTs, GPIO and ADC)
  • Routes interrupt sources to either the ARM920T's IRQ or FIQ (Fast IRQ) inputs
  • Three dedicated off-chip interrupt lines operate as active high level sensitive interrupts
  • Any of the 19 GPIO lines maybe configured to generate interrupts
  • Software supported priority mask for all FIQs and IRQs
Note: For peripheral driver development purpose, notice that the external IRQ lines 5,6 and 7, which are ISA/X86 architecture based, are mapped to EP9302 external interrupt lines 22, 33 and 40, respectively. For further information about interrupts, including the EP9302 interrupt controller and map, refer to the EP9301 User's Guide, chapter 5.

Memory

TS-7250 uses three type of memory. The SDRAM is the fast access volatile memory used to run applications by the processor and the on-board flash is the non-volatile memory used for storage purpose. Flash memory may also be added using USB memory drivers. On-Board SDRAM

The TS-7250 uses 32 MB SDRAM technology to provide 32 or 64 MB of high-speed volatile memory. The memory is soldered directly to the board, making the TS-7250 more reliable in high-vibration environments. The TS-7250's RAM is not contiguous in the physical memory map of the EP9302. But the MMU is programmed to remap the blocks of RAM to appear as a contiguous block of memory at the very beginning of the virtual memory map. In the case of a 256 Megabit SDRAM chip (32 MB), it is located at 0 through 32 MB in the virtual memory map. Refer to the MMU section of this manual to understand how the physical memory is mapped and the virtual memory is translated.

Note: It is possible to use larger sizes of the SDRAM chip than the standard 32 MB one. The TS-7250 is designed to accommodate both 32 MB and 64 MB chips, providing up to 128 MB of RAM memory. Contact Technologic Systems for larger SDRAM sizes.

Battery Backed SRAM

There is a peripheral board available for the TS-7250 named TS-NVRAM that adds 32K bytes or 128 Kbytes or 512K bytes of battery-backed SRAM. Battery backed SRAM provides non-volatile memory with very fast write times and unlimited write cycles, unlike Flash memory. This can be very important if the data is constantly being updated several times per minute, since Flash devices can wear-out after a few million write cycles. It also eliminates the latency that Flash memory has during write cycles, since Flash technology write cycles are about 10-100 times slower than read cycles. The TS-NVRAM peripheral board is located at the PC/104 memory space base address of 0x11AA_0000. This resource is a byte-wide memory device using a lithium battery that is guaranteed to last a minimum of 10 years with or without power applied.

On-Board NAND Flash

The TS-7250 uses a NAND Flash chip for its on-board Flash resource. The physical address of the Flash chip is 0x6000_0000. The first 16KB is reserved for the TSBOOTROM code. The TS-BOOTROM code initializes various internal configuration registers for proper operation, and initializes and tests the SDRAM. The last 3 MB are reserved for the RedBoot ROM monitor, RedBoot FIS (Flash Image System) and RedBoot FCONFIG (Flash configuration). The Linux kernel shipped by default is pre-loaded in the FIS and the default boot script and Ethernet MAC address are contained in the FCONFIG. You may also use the RedBoot FIS to store and load images that contain eCos applications or other OS/RTOS boot loaders. The rest of the on-board flash is used for the Linux YAFFS2 file system. This is a journaling file system that is aware of the wear-out mechanism of the NAND flash and incorporates ECC algorithms at the file system level to maximize Flash lifetime. It is also extremely tolerant of power failures during file write sequences. The entire Flash chip can be write-protected by removing Jumper 3. When JP3 is not installed, the Flash chip becomes a read-only resource.

Note: It is possible to use larger sizes of the NAND Flash than the standard 32 MB chip. The TS-7250 is designed to accommodate both 32 MB and 128 MB chips, providing up to 256 MB of on-board flash. Contact Technologic Systems for larger Flash sizes.
Note: The YAFFS1 file system runs on the TS-7250 boards that feature NAND chips with 512 byte page size, enabling up to 128 MB of on-board flash. The YAFFS2 file system supports the new NAND technology, with 2k page size, hence it will be installed on TS-7250 boards that are configured with 128-256 MB of flash.

USB Flash Drive or Compact Flash Card

Additional non-volatile storage may be added with a USB flash drive or a Compact Flash card. These devices supply additional non-volatile storage either for data or for a complete operation system distribution, such as Debian. A tar-file of Debian is available on the Technologic Systems website. Alternatively, the developer's kit includes a USB flash thumb-drive or Compact Flash card pre-loaded with Debian. Flash memory provided by these devices behaves much as a hard drive does with sizes ranging from 32MB to 1GB. These products are inherently more rugged than a hard drive since they are completely solid-state with no moving parts. However, they have the added advantage of being removable media Use of a Compact Flash card with TS-7250 SBC or higher requires a USB Compact flash adapter, which will also be included in the TS-ARM Development Kit if requested. The USB flash drive has the advantage over a CF card in that the USB drive can be hot swapped. Note Drivers are available in the TS-Linux distribution to support USB flash drives. One can load Debian OS with two scripts provided by the on-board flash TS-Linux file system. First, invoke /usr/bin/loadUSBModules.sh, then run the script /usr/bin/loadUSB.sh to chroot into the Debian OS.

Glue Logic CPLD

The TS-72XX ARM SBC's include a CPLD (a Xilinx 9572 on TS-7200 and TS-7250, or an Altera MAXII on TS-7260) which is responsible for taking control over the internal components communication through glue logic implementation. For instance, the CPLD is used to control the NAND flash through internal registers configuration. The CPLD handles control signals on the PC104 bus, has a watchdog timer, enables jumper settings reading, handles the reset button, interfaces to the real-time clock and controls the EEPROM chip select. It also implements peripheral features that, together with EP9302 modules, makes available an advanced set of communication ports, DIO pins, ADC converters, and others.

The inclusion of a CPLD on the SBC allows customized programming for customers with special needs, without having to do a more expensive board redesign. For example, the MAXII CPLD on the TS-7260 can be configured with three different cores:

  • 2TTLCOM option: 2 extra TTL-only serial ports with TX enable signals and that includes a very simple GPIO core (data direction register and data register only).
  • TS-XDIO option: uber-GPIO that can do quadrature, PWM, freq-counter, pulse timing, IRQ and DRQ, etc
  • SDSOCKET option: a special core for a SD interface that requires a special Linux driver module to be of use.

The CPLD can be programmed using the JTAG header and special software/hardware supporting tools. Contact Technologic Systems for support on CPLD programming software and tools.

Real-Time Clock

The TS-7250 optionally supports a Non-volatile Battery-backed real-time clock (RTC) which is soldered onto the board. This option uses an ST Micro M48T86PC1 module for the real-time clock function. This module contains the lithium battery, 32.768 kHz crystal, and a RTC chip with 114 bytes of battery-backed CMOS RAM. It will maintain clock operation for a minimum of 10 years in the absence of power. The 114 bytes of non-volatile RAM, physically located in the RTC chip, are available to the user. Contact Technologic Systems for driver support. The RTC is accessed using two registers. The write-only index register is located at physical address location 0x1080_0000 and the RTC data register is location at physical address location 0x1170_0000. These are byte-wide registers with the Index Register property of write only. The Data Register has a read/write property. Valid Index Register values are between 0 and 127, decimal. The first 14 index locations are used for accessing the RTC Time and Date registers. The next 114 locations are non-volatile RAM locations. This option is NOT compatible with the TS-5620, a peripheral board that also uses an ST Micro RTC module for real-time clock functionality. While the two options are mutually exclusive, it is possible to use the TS-5620 peripheral board on a TS-7250 that does not have the on-board RTC option installed. Any source code that utilizes the RTC is compatible with both optional installations. The TS-Kernel shipped with the boards includes support for the TS-5620 peripheral board.

Watchdog Timer

The TS-7250 incorporates a Watchdog Timer (WDT) unit. The WDT can be used to prevent a system "hanging" due to a software failure. The WDT causes a full system reset when the WDT times out, allowing a guaranteed recovery time from a software error. To prevent a WDT timeout, the application must periodically "feed" the WDT by writing a specific value to a specific memory location.

Register
 Address
 Access
WDT Control register 0x2380_0000 Read/Write
WDT Feed register 0x23C0_0000 Write Only

The WDT Control register must be initialized with the timeout period desired. This may be as short as 250 mS or may be as long as 8 seconds. After the WDT has been enabled, the WDT counter begins. The application software can reset this counter at any time by "feeding" the WDT. If the WDT counter reaches the timeout period, then a full system reset occurs.

Value
 MSB MID LSB Timeout Period
0x00 0 0 0 Watchdog Disabled
0x01 0 0 1 250 mS
0x02 0 1 0 500 mS
0x03 0 1 1 1 second
0x04 1 0 0 -- Reserved
0x05 1 0 1 2 seconds
0x06 1 1 0 4 seconds
0x07 1 1 1 8 seconds

In order to load the WDT Control register, the WDT must first be "fed", and then within 30 uS, the WDT control register must be written. Writes to this register without first doing a "WDT feed", have no affect. In order to clear the WDT counter (feeding the watchdog), a value of Hex 05 must be written to the WDT Feed register.

By default, a user process does not have the physical address space (access) of the watchdog registers mapped. When using the Linux OS, the watchdog can be reached from user C code by using the mmap() system call on the /dev/mem special file to map the areas of physical address space into process user address space. See section 3.4.

WARNING: Use only the Watchdog Timer implemented by Technologic Systems in the CPLD. The Watchdog Timer included in the EP9302 has serious problems.

Common Interfaces General Information

The purpose of this section is to provide general information about the common interfaces, such as Serial Ports and Digital Input/Output, which appear in more than one header or connector of the TS-7250. For further information on these features, refer to the Connectors and Headers section of this manual.

Serial Ports

The TS-7250 have two asynchronous serial ports (COM1 and COM2) which provide a means to communicate with external serial devices. Each is independently configured as a 16C550- type COM port that is functionally similar to a standard PC COM port. These ports have 16-byte FIFOs in both the receive and the transmit UART channels. Both COM ports can support all standard baud rates up through 230.4Kbaud. Both COM ports may be configured to use a DMA channel (useful when very high baud rates are being used). COM1 and COM2 UARTs can generate:

  • Four individually maskable interrupts from the receive, transmit, and modem status logic blocks
  • A single, combined interrupt that is asserted if any of the individual interrupts are asserted and unmasked

The COM1 port can also support the HDLC protocol. Refer to the Cirrus EP9301 User's Guide for more details. The COM2 port can optionally support RS-485 half or full duplex levels.

Digital I/O

There are 20 Digital Input/Output (DIO) lines available on the TS-7250 . These are available on two headers labeled "DIO" and "LCD". The header labeled LCD can be used as 11 DIO lines or as an alphanumeric LCD interface. The header labeled DIO has 9 DIO pins available. In addition to the DIO signals, each header also has a power pin and Ground available. The LCD header has 5V power available while the DIO header has 3.3V power.

The DIO2 header (FPGA DIO) is controlled by the on-board FPGA. It is a 40-pin header divided in two sub-headers of 20 pins each. On the first header, by default, there are 17 video signals that can be changed into digital I/O, while the second, labeled DIO2, has 18 digital I/O lines which implement two XDIO ports. Thus, there are 35 total DIO lines connected directly to the on-board FPGA on the TS-7250 available through the 40-pin header. The first header has 5V power available and the second (DIO2) has 3.3V power. Three pins on the DIO header are used to bring out the EP9302 SPI bus. By using some of the DIO pins as peripheral Chip Select signals, a complete interface is available for SPI peripherals. It is also possible to bring out a fourth SPI bus function [SPI_Frame] by adding a 10 ohm resistor in the position labeled R1 on TS-7250 boards. This signal is not required for many SPI peripherals but it may prove useful in some applications. All of the DIO lines are programmable as either inputs or outputs and the direction of each I/O pin can be individually programmed. All DIO control registers are 8-bits wide and aligned on word (32-bit) boundaries. For all registers, the upper 24 bits are not modified when written and are always read back as zeros. Every DIO pin has two registers used to access it, an 8-bit data register and an 8-bit data direction register (DDR). The DDR controls whether each DIO pin is an input or an output ("1" = output). Writing to the data register only affects pins that are configured as outputs. Reading the data register always returns the state of the DIO pin.

Many of the DIO pins (DIO_0 thru DIO_8 and LCD_0 thru LCD_7) can also be programmed to cause interrupts. The interrupt properties of these pins are individually configurable. Each interrupt can be either high or low level sensitive or either rising or falling edge triggered. It is also possible to enable debouncing on any of these interrupts. Debouncing is implemented using a 2-bit shift register clocked by a 128 Hz clock. Refer to the [EP9301 User's Guide] and see Chapter 21 for details The 5V power output pin on the LCD Header is current limited to 1000mA to prevent excessive current. The 3.3V power on the DIO1 Header is current limited to approximately 1 Amp by a 3.3V regulator.

A/D Converters

The EP9302 A/D converter is standard on all TS-7250 boards. The Cirrus EP9302 features a 5 channel, 12-bit Analog to Digital Converter with an analog multiplexor, with an input range of 0 to 3.3 V.

On the TS-7200, only the top and bottom channels (ADC0 and ADC4) are brought out on the DIO1 Header. On the TS-7250, the dedicated A/D Header brings out all the 5 EP9302 A/D channels. The TS-7260 uses 3 of the 5 EP9302 A/D channels for on-board measurements, therefore only 2 channels are available on the DIO2 Header. The TS-7200 and TS-7250 support an optional 8 channel, 12-bit A/D converter (ADC) with a conversion time of 12 uS through the MAX 197 chip. This will allow up to 60,000 samples per second. The dedicated MAX197 A/D Header brings out all the 8 A/D channels.

Connectors and Headers

10/100 Base-T Ethernet Connector

The EP9302 Ethernet LAN controller incorporates all the logic needed to interface directly to any MII compatible Ethernet PHY chip. A low-power Micrel KS8721 chip is used to implement the Ethernet PHY function and an integrated RJ-45 connector with built-in 10/100 transformer and LED indicators completes the Ethernet sub-system. The TS-7250 has both a LINK/ACTIVITY LED and a 10/100 speed LED built into each RJ- 45 connector that indicates the current Ethernet status. The LINK LED (left side of connector, green) is active when a valid Ethernet link is detected. This LED should be ON whenever the TS-7250 is powered and properly connected to a 10/100BaseT Ethernet network. The LINK/ACTIVITY LED will blink to indicate network activity for either inbound or outbound data. The SPEED LED (right side of connector, amber) will be on when a 100Mb network is detected and off for a 10Mb network. Both of these LEDs are controlled by the KS8721 and do not require any overhead by the processor. The Ethernet PHY chip can be powered down, under software control, to save approximately 90 mA of current consumption. This is controlled by the EP9302 Digital output on Port H, bit 2. A logic zero will power down the KS8721 PHY interface.

Note: TS-Linux provides all the software support to use the EP9302 10/100 Ethernet core. For more details, find the TCP/IP configuration instructions on the TS-Linux documentation.

USB Connector

The USB Connector on the TS-7250 provide two USB interfaces for the user. These are directly connected to the EP9302 processor, which integrates an USB dual-port Open Host Controller Interface (Open HCI), providing full-speed serial communications ports at a baud rate of 12 Mbits/sec. Up to 127 USB devices (printer, mouse, camera, keyboard, etc.) and USB hubs can be connected to the USB host in the USB "tiered-star" topology. This includes the following features:

  • USB 2.0 compatible
  • Open HCI Rev 1.0 compliant
  • USB device connections support at both low-speed (1.5 Mbps) and full-speed (12 Mbps)
  • Root HUB integrated with 2 downstream USB ports
  • Transceiver buffers integrated, over-current protection on ports
  • Supports power management
  • Operates as a master on the bus
Note: TS-Kernel implements all the necessary driver support to enable the USB OHCI. Also, a wide variety of USB drivers for devices such as mouse, keyboard and flash memory are available. Refer to the Linux for TS-ARM User's Guide or contact us for further information on how to integrate an USB device and an USB Linux driver with your TS-7250.

COM1 Connector

The COM1 RS-232 port uses a DB-9 male connector on the TS-7250.

Table: COM1 DB9 Pin-Outs
DB9 Pin Signal Description
1 DCD Data Carrier Detect
2 RXD Receive Data
3 TXD Transmit Data
4 DTR Data Terminal Ready
5 GND Ground
6 DSR Data Set Ready
7 RTS Request to Send
8 CTS Clear to Send
9 -- --

The base address of COM1 appears in the physical address space at 0x808C_0000.

Technologic Systems provides software drivers to access this port. This full complement of RS-232 signals (all except Ring Detect) allows COM1 to interface to almost any serial RS-232 device.

COM2 Header

The base address of COM2 appears in the physical address space at 0x808D_0000. Technologic Systems provides software drivers to access this port. COM2 has RS-232 support only for the TXD and RXD signals. This is sufficient to interface with serial devices that only require transmit and receive data lines. COM2 is accessible on a 10-pin header labeled COM2.

TX- NC NC RX- NC
6 7 8 9 10
1 2 3 4 5
TX+ RXD TXD RX+ GND
Note: The COM2 serial port header uses a non-standard numbering scheme. This was done so the header pins would have the same numbering as the corresponding DB-9 pin; i.e. pin 3 (TXD) on the header connects to pin 3 on the DB-9.
COM2 Header DB9 Connector RS-232 Half Duplex RS-485 Full Duplex RS-485
1 1 TX+ / RX+ TX+
2 2 RXD
3 3 TXD
4 7 RX+
5 5 GND GND GND
6 6 TX+ / RX+ TX-
7 7
8 8
9 9 RX-
10 -- -- -- --

Adapter cables are available to convert COM2 to a standard 9-pin SubD male connector. In addition, COM2 has optional support for full or half-duplex RS-485

Note: The COM2 serial port 10-pin header has both RS-232 and RS-485 signals. Only one set may be used for a given application - it is not possible to use both at the same time.


Optional RS-485 Support

The COM2 Port supports RS-485 half duplex or full duplex operation. RS-485 drivers allow communications between multiple nodes up to 4000 feet (1200 meters) via twisted pair cable. Half-duplex RS-485 requires one twisted pair plus a Ground connection, while full duplex requires two twisted pair plus a Ground. For half-duplex operation, a single twisted pair is used for transmitting and receiving.

The ioctl Linux system call is used to initialize the automatic RS-485 control logic. For full-duplex operation, two twisted pairs are used and the transmit driver is typically enabled all the time. Fail-safe bias resistors are used to bias the TX+, TX- and RX+, RX- lines to the correct state when these lines are not being actively driven. In a typical RS-485 installation, the RS-485 drivers are frequently "tri-stated." If fail-safe bias resistors are not present, the RS-485 bus may "float" and small amounts of noise can cause spurious characters at the receivers. 4.7K Ohm resistors are used to pull the TX+ and RX+ signals to 5V and also to bias the TX- and RX- signals to ground.

Termination resistors in many installations are not required when cable lengths are less than 50 meters and the baud rate is 9600 or less. Termination resistors may be required for reliable operation when running longer distances or at higher baud rates. Termination resistors (typically 100-150 ohms) should only be installed at each end of an RS-485 transmission line. In a multi-drop application where there are several drivers and/or receivers attached, only the devices at each end of the transmission line pair should have termination resistors.

A read at I/O location 0x2240_0000 bit 1 will return a "1" when the RS-485 option is installed.

Note: A special ioctl command has been added to the TS-Kernel's serial code to turn off and on the automatic RS-485 feature. Refer to the Linux for TS-ARM User's Guide for additional software information on RS-485 support.

RS-485 Quick-Start Procedure

Perform the following steps:

  1. Check that the RS-485 option is installed in the TS-7250 (required).
  2. Attach the RS-485 cable to the 10-pin header. (Adapter cables to SubDB9 connector are available from Technologic Systems).
  3. Set the COM2 UART serial parameters (baud rate, data, parity, and stop bits, interrupts, etc) in your source code.
  4. Use the TIOC_SBC's485 ioctl() to enable the automatic RS-485 feature.
  5. Simply read() and write() data to the COM2 UART - the automatic RS-485 logic controls TX enable.

Automatic RS-485 TX Enable

The TS-7250 supports fully automatic TX enable control under hardware control. This simplifies the design of half-duplex systems since turning off the transmitter and enabling the receiver in software is typically difficult to implement. If this is implemented in software, then the COM2 UART transmit holding register and the transmit shift register both must be polled until empty before deasserting the TX enable signal to the RS-485 driver. The design gets more complicated when using the TX FIFO or when using a multi-tasking OS such as Linux.

The implementation on the TS-7250 uses hardware to automatically control when the RS-485 drivers and receivers are selected. The automatic RS-485 logic eliminates the need for any software polling and supervision. This circuit automatically turns on/off the RS-485 transceiver and receiver at the correct times. This only requires the COM2 Mode registers to be initialized once based on baud rate and data format.

Value MSB MID LSB Mode
0x00 0 0 0 RS-232
0x01 0 0 1 Full-Duplex RS-485
0x02 0 1 0 -- Reserved
0x03 0 1 1 -- Reserved
0x04 1 0 0 Half-Duplex 9600 Baud
0x05 1 0 1 Half-Duplex 19.2Kbaud
0x06 1 1 0 Half-Duplex 57.6Kbaud
0x07 1 1 1 Half-Duplex 115.2Kbaud

COM2 will default to RS-232 mode at reset (COM2 mode register = Hex 00). In order to switch COM2 into Full duplex RS-485 mode, the COM2 Mode register at 0x22C0_0000 must be set to Hex 01. In this mode, the TX drivers are always asserted.

In order to switch COM2 into half-duplex RS-485, then the COM2 mode register at 0x22C0_0000 must be set to Hex 04, 05, 06 or 07 depending upon the baud rate required. A second COM2 Mode register at 0x2300_0000 must be set to Hex 01 if the COM2 is in half-duplex mode and the data format is using 8 data bits with parity or 8 data bits with 2 stop bits.

Note: COM2 in half-duplex RS-485 supports baud rates of 9600, 19.2K, 57.6K and 115.2K. If you need to operate at any other baud rate, then please contact Technologic Systems.

DIO1 Header

The DIO1 Header provides +3.3V, GND, and 9 digital I/O lines that may be used to interface the TS-7250 with a wide range of external devices. DIO lines DIO_0 thru DIO_7 are a byte-wide port using Port B on the EP9302 and are accessed via the data register at address location 0x8084_0004. The DDR for this port is at address location 0x8084_0014.

DIO1 Pin Default Signal TS-7200
1 DIO_0
2 GND
3 DIO_1
4 Port_C0 ADC0
5 DIO_2
6 SPI_Frame ADC4
7 DIO_3
8 DIO_8 ADC4
9 DIO_4
10 SPI_MISO
11 DIO_5
12 SPI_MOSI
13 DIO_6
14 SPI_CLK
15 DIO_7
16 +3.3V

DIO_8 is accessed via bit 1 of Port F in the EP9302. The Port F data register is at address location 0x8084_0030. The DDR address for this port is location 0x8084_0034.

The Pin 4 of the DIO1 Header, in the default configuration, is accessed via bit 0 of Port C in the EP9302. The address location 0x8084_0008 is Port C Data Register and 0x8084_0018 is Port C Directon Register.

When accessing these registers, it is important not to change the other bit positions in these Port F registers. Other DIO1 Port functionality, used for dedicated TS-7250 functions, utilize these same control registers. All accesses to these registers should use read-modify-write cycles.

WARNING: All pins on the DIO header use 0-3.3V logic levels. Do not drive these lines to 5V.

When the DIO pins are configured as outputs, they can "source" 4 mA or "sink" 8 mA and have logic swings between GND and 3.3V. When configured as inputs, they have standard TTL level thresholds and must not be driven below 0 Volts or above 3.3 Volts. DIO lines DIO_0 thru DIO_3 have 4.7K Ohm "pull-up" resistors to 3.3V biasing these signals to a logic"1". The other DIO pins have 100K Ohm bias resistors biasing these inputs to a logic "1".

SPI Interface

The EP9302 Synchronous Serial Port is available on the DIO1 header. This port can implement either a master or slave interface to peripheral devices that have either Motorola SPI, or National Semiconductor Microwire serial interfaces.

The transmit and receive data paths are buffered with internal FIFO memories allowing up to eight 16-bit values to be stored for both transmit and receive modes. The clock rate is programmable up to 3.7 MHz and has programmable phase and polarity. The data frame size is programmable from 4 to 16 bits.

By using some of the DIO1 Header pins as peripheral Chip Select signals, a complete interface is available for addressing up to 9 SPI peripherals. The SPI bus pins are defined in the table below:

DIO1 Pin Name Function
10 SPI_MISO Master In/Slave Out
12 SPI_MOSI Master Out/Slave In
14 SPI_CLK Clock
6 SPI_Frame SPI Frame pin

A fourth SPI bus function [SPI_Frame] is available by adding a 10 ohm resistor in the position labeled R1 on TS-7300. This signal is not required for many SPI peripherals but it may prove useful in some applications.

WARNING: The SPI bus pins use 0-3.3V logic levels. Do not drive these lines to 5V.

Refer to the EP9301 User's Guide and see Chapter 19 for more details on using SPI bus.

Matrix Keypad

DIO signals DIO_0 thru DIO_7 are physically arranged to allow a 16-pin (2x8) ribbon cable to directly connect a 4x4 matrix keypad. Sample code is available for the Matrix Keypad. Contact Technologic Systems for further information.

A/D Header - Cirrus EP9302

The EP9302 A/D converter can do a maximum of 925 samples per second, and requires a settling time of 2 milliseconds between channel switches. Note that the Cirrus A/D converter is not the same as the optional, full-featured MAX197 A/D converter. To maintain 12-bit accuracy, the analog signal being measured must have a low source impedance (less than 10 ohms). Otherwise, an operational amplifier may need to be added to buffer the A/D input. The EP9302 A/D converter should not be driven by a source impedance greater than 10 ohms to ensure accurate results (the EP9302 A/D converter has an input impedance that is not completely linear and may be as low as 10K ohms). For detailed information, please see the Cirrus EP9301 User's Guide, page 518. For high-performance applications, the optional MAX197 A/D converter is preferred.

Table: ADC Switch Values (EP9302)
Input to Measure ADC Switch Value
ADC0 0x0000_0608
ADC1 0x0000_0680
ADC2 0x0000_0640
ADC3 0x0000_0620
ADC4 0x0000_0610
Table: A/D Header Pin Out (EP9302)
GND GND GND GND GND
2 4 6 8 10
1 3 5 7 9
ch0 ch1 ch2 ch3 ch4

The following steps outline the software execution to use the Cirrus A/D converter:

  1. Unlock the software lock before setting the TSEN bit in the ADCClk register by writing 0xAA to the ADCSWLock register (0x8090_00C0). "OR" in the TSEN bit (bit 31) to the ADCClkDiv register (0x8093_0090)
  2. Unlock the software lock (again) before OR'ing in the ADCEN (ADC clock enable, bit 31) to 0x8093_0080
  3. Clear bit 2, the ADCPD (ADC Power Down) bit, at 0x8093_0080. This bit MUST be set to 0 (see page 91 of the EP9301 User's Guide)
  4. After unlocking the software lock, write the channel's magic value (see Cirrus EP9301 User's Guide, table 20-2) to the ADCSwitch register (0x8090_0018) to select that channel for the next data acquisition
  5. Poll the ADCResult register (0x8090_0008) until bit 31 is not set
  6. Using a 32 bit read operation, read the result from 0x8090_0008, masking off the upper 16 bits

Interpreting Cirrus A/D Converter

The Cirrus on-chip A/D converter is a successive approximation A/D converter. Each A/D channel is calibrated on the TS-7250 and these 16-bit values are stored in non-volatile EEPROM. These calibration values minimize the offset errors and gain errors in the EP9302 A/D. It is important for the user program to use these values as per our sample code, which can be found either on our website or in the CD included in the Developer's Kit. Two reference points, 0 and 2.5 Volts, with the corresponding reference values stored in EEPROM. Bytes 0x07EB through 0x07FE of the EEPROM hold a two dimensional array: [channel number][0V ref. point, 2.5V ref. Point] The reference points are stored as a 16 bit value, and should be used to correlate the values returned by the Cirrus A/D converter to voltage.

A/D Header - Optional MAX197

The TS-7250 supports an optional eight-channel, 12-bit A/D converter (ADC) with a conversion time of 12 uS. This will allow up to 60,000 samples per second. Each channel is independently software programmable for a variety of analog input ranges: -10V to +10V, -5V to +5V, 0V to +10V, or 0V to +5V. This allows an effective dynamic range of 14 bits.

Table: A/D Registers (MAX197)
I/O Address Action
0x10F0_0000 Write Initiate A/D Conversion
0x10F0_0000 Read LSB of Conversion
0x10F0_0001 Read MSB of Conversion
0x2240_0000 Read Bit 0 = 1 if A/D option installed
0x1080_0000 Read Bit 7 = 0 when Conversion completed

Each channel is overvoltage tolerant from -16V to + 16V, and a fault condition on any channel will not affect the conversion result of the selected channel. This is all accomplished with a 5V only power supply; no negative supply voltage is required. The Maxim MAX197 chip can be replaced with a MAX199 chip if a lower range of analog input levels is required (-4V to +4V, -2V to +2V, 0V to 4V, and 0V to 2V).

A/D Control Register (0x10F0_0000 Write)
Bit Description Details
0-2 Analog channel select Channels 0-7
3 Unipolar / Bipolar 0 = Unipolar (i.e. 0 to +5V)
1 = Bipolar (i.e. -5V to +5V)
4 Range select 0 = 5V range
1 = 10V range
5-7 Mode bits Set to 0, 1, 0

A read at I/O location 0x2240_0000 bit 0 returns a "1" when the A/D option is installed on the TS-7250.

Single Sample Acquisition Procedure

An acquisition is initiated by writing to I/O location 0x10F0_0000. The value written to this location determines the channel to convert (bits 0-2) and selects one of four input ranges (bits 3 and 4). Bits 5, 6, and 7 should be set to 0, 1, 0 respectively. After the write cycle to location 0x10F0_0000, the MAX197 completes the A/D conversion in about 12 mS. Bit 7 at I/O location 0x2240_0000 may be polled to determine when the conversion is complete (zero = complete). The conversion result is now available at locations 0x10F0_0000 (LSB) and 0x10F0_0001 (MSB). A single word read at 0x10F0_0000 can also be used. When using unipolar modes, the result is in binary format with the upper 4 bits of the MSB equal to zero. When a bipolar mode is used, the result is in twos-complement binary with the upper 4 bits (Bits 12-15) equal to bit 11 (sign extended).

Table: A/D Header Pin Out (MAX197)
GND GND GND GND GND GND GND GND
2 4 6 8 10 12 14 16
1 3 5 7 9 11 13 15
ch0 ch1 ch2 ch3 ch4 ch5 ch6 ch7

If more details on the A/D converter specifications are required, go to the Maxim web site and search for MAX197.



Product Notes

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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

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