IBM PC 100, Техническое руководство

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Chapter 2. Connectors and Jumpers
However, if the computer comes with an internal modem, the factory settings and COM assignments are:
Serial A: 3F8h-IRQ 4 (COM1)
Serial B: 2F8h-IRQ 3 (COM2)
Modem: 3E8h-IRQ 5 (COM3)
The port address and IRQ settings for Serial A and Serial B can be viewed using the Configuration/Setup
Utility program. The COM numbers are not shown on the Configuration/Setup Utility program screens.
However, you can use one of the diagnostic programs that comes with your computer to view them.
Parallel Port Connector
The parallel port connector is a standard 25-pin, D-shell connector. The following figure shows the signal
and pin assignments for the parallel port connector.
13 1
25 14
The parallel port supports extended, high-speed modes, which means that it can transfer data up to 10
times as fast as a standard parallel port.
Figure 24. Parallel Port Connector Signal and Pin Assignments
Pin I/O Signal Name Pin I/O Signal Name
1 O -STROBE 14 O -AUTO FD XT
2 I/O Data bit 0 15 I -ERROR
3 I/O Data bit 1 16 O -INIT
4 I/O Data bit 2 17 O -SLCT IN
5 I/O Data bit 3 18 NA Ground
6 I/O Data bit 4 19 NA Ground
7 I/O Data bit 5 20 NA Ground
8 I/O Data bit 6 21 NA Ground
9 I/O Data bit 7 22 NA Ground
10 I -ACK 23 NA Ground
11 I BUSY 24 NA Ground
12 I PE 25 NA Ground
13 I SLCT
Chapter 2. Connectors and Jumpers
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