Making a DIY programming cable for the Tait 8105 Radios

I am currently building a project that utilises two Tait 8105 UHF radios. I needed to upgrade the firmware and configure the radios, but couldn't find a programming lead in the UK for sensible money. After a bit of research, I managed to build my own using a FTDI TTL-232RL USB adapter and a DB9 Breakout board.

Using UDEV rules to ensure a USB serial device always links to the same location in /dev/

If you're using several USB serial adapters on a linux machine, you may have found that their /dev/ names change after a reboot. This can be frustrating if each serial port is plugged into a specific device and you want to always access it using the same /dev/ name.

Fortunately, udev rules exist that allow you to symlink a serial device to a name, persistently. Udev rules are very powerful and support lots of tweaking, but for now I will cover the basics of assigning a USB serial device a static name.