This is to allow two DigiCarts to roll simultaneously from a single RC-220 or 320. The RC-220 talks to both units, but only the ‘master’ unit’s transmit pins are connected back to the RC-220. The lines from the ‘slave unit’ get disconnected so that they do not reach either the ‘master’ unit or the RC-220.
DigiCart Serial Port Pinout
Pin Number /Signal
2 /+5 Volts (Not normally used)
4 /TX+ (This is Rx+ on the RC-220) Cut this signal between the two DigiCarts for slave mode operation.
5 /TX- (This is Rx- on the RC-220) Cut this signal between the two DigiCarts for slave mode operation.
6 /HSK Out (Not normally used)(RC-220 alternate +9 volt power)
7 /HSK In (Not normally used)(RC-220 alternate +9 volt power)
Pins 4 and 5 are the ones you want to interrupt between the “master unit” and “slave unit”. If you put a switch on these lines, it is possible to easily go back to normal two machine selection.
Set both units to the same Remote Address. If you have the switch installed, when going back to normal independent operation remember to set the second unit back to Remote Address 2.
Proper operation depends on precisely matching the Index numbers (the Drive, Directory and Cut ID numbers).
It is advisable to match most of each corresponding cut name for operator confirmation.)