IBM PS/1 User Manual

Parallel Port
Pin Signal Name I/O Pin Signal Name I/O
1 Strobe O 14 Auto Feed NA
2 Data Bit 0 I/O 15 Error I
3 Data Bit 1 I/O 16 Initialize O
4 Data Bit 2 I/O 17 Select (In) O
5 Data Bit 3 I/O 18 Ground Power
6 Data Bit 4 I/O 19 Ground Power
7 Data Bit 5 I/O 20 Ground Power
8 Data Bit 6 I/O 21 Ground Power
9 Data Bit 7 I/O 22 Ground Power
10 Acknowledge I 23 Ground Power
11 Busy I 24 Ground Power
12 Paper Empty I 25 Ground Power
13 Select O
Parts/Test Point Locations 5-21

IBM PS/1 Specifications

General

Processor	Intel 80286 or 80386
Processor Speed	10 MHz (80286)
RAM	1 MB (expandable to 2 MB or more)
Storage	40 MB hard drive
Floppy Drive	3.5" 1.44 MB
Graphics	VGA
Ports	Serial, Parallel, Mouse