IBM 8681 Hardware Maintenance Manual - Page 80

The following table shows the pin-number assignments for the serial-port connectors. Table 4. Serial port pin-number assignments Pin Signal Pin Signal 1 Data carrier detect 2 Receive data 3 Transmit data 4 Data terminal ready 5 Signal ground 6 Data set ready 7 Request to send 8 Clear to send 9 Ring indicator When you turn on the server, the POST routine assigns the serial ports to specific communication port addresses. Some application programs use only certain ports, and some modems are designed for use only at certain communication port addresses. You might need to use the Configuration/Setup utility program to change communication port address assignments to resolve conflicts. Parallel port: The parallel port usually is used to communicate with printers, and transfers data one byte at a time using DMA. The parallel port has a 25-pin, female D-shell connector on the back of the server. (Refer to "Input/output connectors and expansion slots" on page 122 for the location of the connector.) 13 1 25 14 The following table shows the pin-number assignments for the parallel-port connector. Table 5. Parallel port pin-number assignments Pin Signal Pin Signal 1 STROBE 2 Data 0 3 Data 1 4 Data 2 5 Data 3 6 Data 4 7 Data 5 8 Data 6 9 Data 7 10 -ACK 11 BUSY 12 PE (paper end) 13 SLCT (select) 14 -AUTO FEED XT 15 -ERROR 16 -INIT 17 -SLCT IN 18 Ground 19 Ground 20 Ground 21 Ground 22 Ground 23 Ground 24 Ground 25 Ground When you turn on the server, the POST routine assigns the parallel port a specific port address. You can change 72 Netfinity Server HMM