IBM Personal System/2 50 - POS Address Map

POS Address Map
The following figure shows the organization of the I/O address space
used by POS. The POS registers are 8-bit registers. Bit 0 of POS
Register 2 and bits 6 and 7 of POS Register 5 are defined. All other
bits in POS Registers 2 through 5 are free-form.
Address Function
(Hex)
0094 System Board Enable/Setup Register
0096 Adapter Enable/Setup Register
0100 POS Register 0~ Adapter Identification Byte (Low Byte)
0101 POS Register 1— Adapter Identification Byte (High Byte)
0102 POS Register 2— Option Select Data Byte 1
Bit 0 is Card Enable.
0103 POS Register 3— Option Select Data Byte 2
0104 POS Register 4— Option Select Data Byte 3
0105 POS Register 5— Option Select Data Byte 4
Bit 7 is the channel check active indicator.
Bit 6 is the channel check status-available indicator.
0106 Reserved
0107 Reserved
Figure 2-1. POS I/O Address Map
Model 50 POS ~ October 1990 2-5