NCR 7452, User Manual

Page: 204 / 261

4-40 Chapter 4: Setup
I/O Addresses (4xxx)
The following I/O Address Map applies to the workstation.
Port (Hex) System Use
0000 - 000F PIIX4 - DMA 1
0020 - 0021 PIIX4 - Interrupt Controller 1
0026 - 0027 SMM Configuration Registers
0040 - 0043 PIIX4 - Timer 1
0060 Keyboard Controller Data Byte
0061 PIIX4 - NMI, Speaker Control
0064 Kbd Controller, CMD/STAT Byte
0070, bit 7 PIIX4 - Enable NMI
0070, bits 6:0 PIIX4 - Real Time Clock, Address
0071 PIIX4 - Real Time Clock, Data
0080 - 008F PIIX4 - DMA Page Register
0092 Fast CPU and Gate A20
00A0 - 00A1 PIIX4 - Interrupt Controller 2
00C0 - 00DF PIIX4 - DMA 2
00E0, 00E1 Super I/O GPIO Control (cash drawer)
00F0 - 00F1 Reset Numeric Error
00EX X=0,2,4 or A – SMC GPIO Address
00EX+1 X=1,3,5 or B – SMC GPIO Data
01CE – 01CF VGA
0170 - 0177 Secondary IDE Channel
01F0 - 01F7 Primary IDE Channel
0220 – 0227 On-Board Serial Port 3
0228 – 022F On-Board Serial Port 4
0240 – 024F Audio