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How to use RT Systems cables with CHIRP on Linux - Dave's World

Using RT Systems cables on Linux

I prefer to use CHIRP for programming my radios since I can easily copy channels between different models of radio and since it is free software. However, it's not always easy to find a generic programming cable for any given radio. RT Systems makes proprietary programming software that you have to buy for each model of radio you have, but some retailers will sell you their programming cables without a software license.

These programming cables are just FTDI serial cables with a proprietary vendor and product code, so operating systems fail to identify the correct driver to load for them. On Windows, this would be a matter of installing RT Systems' own driver package, but on Linux, we can simply use udev to create a simple rule to identify all RT Systems products as FTDI serial compatible.

The Driver

If your distro does not ship it by default, you'll need to install the ftdi_sio kernel module.

The udev rule

I put my rule in /etc/udev/rules.d/99-custom.rules. You can choose your own file name here, but I recommend starting its name with "99" to make sure it only runs after all other udev rules have processed it.

Here are the contents of the file:

ATTR{idVendor}=="2100", RUN+="/sbin/modprobe -q ftdi_sio", RUN+="/bin/sh -c 'echo 2100 $attr{idProduct} >/sys/bus/usb-serial/drivers/ftdi_sio/new_id'"

2100 is the vendor ID for RT Systems. This rule tells udev to run two commands when it detects an RT Systems cable. First, it loads the ftdi_sio driver module if it is not already loaded. Then, it sends a signal to the driver to load it for the vendor ID and product ID of the device it just detected.

Now what?

Once you've got this written, the udev daemon should automatically reload the rules. If you already have the cable connected, unplug it now and plug it back in. The rule will identify the cable, and you can check dmesg to see which device node has been assigned to it. It will resemble /dev/ttyUSB0. You can then tell CHIRP to use that device and get to programming!