• HasGPIbToDCDb flag tells if socket 7 (GPI = General Purpose Input) of serial port B (printing port) is linked to DCD socket (Data Carrier Detect) of the serial comm. controller. Allow synchronous connections.

• HasGPIaToRTxCa flag tells if socket 7 (GPI = General Purpose Input) of serial port A (modem port) is linked to RTxC socket (clock input) of the serial comm. controller.

• HasGPIaToDCDa flag tells if socket 7 (GPI = General Purpose Input) of serial port A (modem port) is linked to DCD socket (Data Carrier Detect) of the serial comm. controller. Allow synchronous connections.