The only cable you need is a serial cable. The 20 pin connector is for IOs. Also, CalAmp devices supports over the air updates, so once your device is connected, you can use the CalAmp portal (PULS) to download a new program to the device.
Hi @jdewitt, ¿what pins are the RS232 Rx-Tx pins in the 20 pin conecctor at a LMU-1200 device?
¿Do you have a layout for connect the device with the PC?
I have some units from one client that he want to reprogram, i don't know what configuration have actually..