TS-MODEM

TS-MODEM

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Schematic
Manual

Overview

The TS-Modem is an add-on PC/104 modem daughter board. It adds one AT-command style compatible Modem that can be directly connected to a dial-up telephone line. The modem interface is a 16C550A compatible UART with 16 byte TX/RX FIFOs. The I/O port address and the IRQ used can be set with jumper blocks on the board itself. Typically, the TS-Modem comes with a 33Kbaud modem, though it can be purchased with the optional feature of a 56Kbaud modem. The TS-Modem can also be purchased with the optional 16-bit PC/104 connector, which is required if using IRQ 10, 11, 12,14, or 15. The TS-Modem can also be purchased with the optional on-board speaker, which is useful during development to monitor call progress. The modem speaker can be turned off by removing a jumper.

Quick Start Guide

This guide is intended to provide a quick example for how to get a PC104 UART device up and running. The instructions below represent the use of a TS-7800 SBC. The procedure for other SBC will vary slightly between models.

These lines of code can be added to a convenient place in the linuxrc, or typed in manually from the initial ramdisk (initrd) before Debian has been loaded. The demonstration board is jumpered for COM4 on IRQ 7.

pc104on
insmod /mnt/root/lib/modules/<version>/kernel/drivers/serial/ts7800_isa16550.ko io=0x2E8 irq=7
mdev -s

Note \<version\> must be replaced with your applicable linux kernel version (as of this authoring, 2.6.24-ts or 2.6.34). You can discover what tty device the modem was installed on by typing:

dmesg | grep serial

The output from this command will look something like this:

serial8250.0: ttyS0 at MMIO 0xf1012000 (irq = 3) is a 16550A
serial8250.1: ttyS1 at MMIO 0xf1012100 (irq = 4) is a 16550A
serial8250: ttyS2 at MMIO 0xee0002e8 (irq = 71) is a 16550A

Note the third serial port's IRQ has been assigned as 71 instead of 7. This is due to the manner in which the TS-7800 handles the PC104 bus, and will be different between different SBC models.
Finally, to test the modem has been installed and is ready to use, use your favorite terminal program to talk to the modem. In the case of our example:

ts7800:~# picocom /dev/ttyS2 -b38400
picocom v1.4

port is        : /dev/ttyS2
flowcontrol    : none
baudrate is    : 38400
parity is      : none
databits are   : 8
escape is      : C-a
noinit is      : no
noreset is     : no
nolock is      : no
send_cmd is    : ascii_xfr -s -v -l10
receive_cmd is : rz -vv

Terminal ready
at
OK
atz
OK
ath0
OK

Note the default baud rate to communicate with the modem is 38400.

Jumpers

There are several jumper settings which are important to the operation of the TS-MODEM. These are described in the table and following paragraph below:

JP	Desc
-	-	-	-	-	-	-	-

Higher COM and IRQ can be selected by combining the above jumpers with an additive effect. Eg. COM1 + COM3 = COM4, or IRQ3 + IRQ4 = IRQ7. The board's stated maximums are COM6 and IRQ 15, however this will also be dependent on the controlling SBC, as some do not support all IRQ on the PC104 bus. I/O addresses for the upper COM ports are listed thus:

-	-	-	}