“P” usually indicates Privacy Plus (Trunking). The same Commercial Series CPS works, but you may need separate trunking system keys.
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You cannot use a standard USB cable. You need an or a "RIB-less" cable specifically designed for the Motorola Professional series. “P” usually indicates Privacy Plus (Trunking)
A stable 13.8V DC power supply to power the GM3688 during the read/write process. Never program a radio powered only by a weak battery or unstable source. Step-by-Step Installation Guide motorola gm3688 programming software download