E497-A (48 TTL I/O channels) ConnectorPPIDescription CN48255_1TTL I/O channels CN28255_2TTL I/O channels For what concern the relation between the ports of both 82C55 and the I/O channels, refer to thefollowing table. CN2 and CN4 SignalPinPinSignal A[7]12GND A[6]34GND A[5]56GND A[4]78GND A[3]910GND A[2]1112GND A[1]1314GND A[0]1516GND C[7]1718GND C[6]1920GND C[5]2122GND C[4]2324GND C[3]2526GND C[2]2728GND C[1]2930GND C[0]3132GND B[7]3334GND B[6]3536GND B[5]3738GND B[4]3940GND B[3]4142GND B[2]4344GND B[1]4546GND B[0]4748GND VCC4950GND 7