computer
4 PS2 6-pin connector for connecting stations with this data interface
5 3-ring stereo audio jack for connecting to the computer's speaker
6 3-ring 3.5mm jack for connecting the radio's straight key for
computer transmission
7 4-ring stereo audio jack for connecting computers and mobile
phones with this interface, or other terminals
8 XH2.54 custom radio interface, the pin definition moves from left to
right in order of GND/SPK/PTT/MIC
9 Grounding
Serial port control instructions
PTT VIA RTS CW VIA DTR
