Personal Computer Maintenance & Service Guide
Table Of Contents
- NOTICE
- CONTENTS
- ABOUT THIS GUIDE
- PRODUCT DESCRIPTION
- SPARE PARTS
- REMOVAL AND REPLACEMENT PRELIMINARIES
- REMOVAL AND REPLACEMENT PROCEDURES
- 4.1 Disassembly Sequence Chart
- 4.2 Disassembly Preparation
- 4.3 Feet Installation
- 4.4 Logo Plate
- 4.5 Cable Lock
- 4.6 Access Panel
- 4.7 Front Bezel
- 4.8 Power Button
- 4.9 Subpanel and Bezel Blanks
- 4.10 Power Switch
- 4.11 Mass Storage Devices
- 4.12 Removing the Drivelocks
- 4.13 Expansion Boards
- 4.14 Board Guide
- 4.15 System Memory
- 4.16 AGP Graphics Board (440BX)
- 4.17 Processor Components
- 4.18 System Board
- 4.19 Internal Speaker
- 4.20 Lithium Battery
- 4.21 Fan Assembly
- 4.22 Power Supply
- 4.23 Converting a Desktop to a Minitower
- 4.24 Converting a Minitower to a Desktop
- CONNECTORS, JUMPERS, AND SWITCHES
- SPECIFICATIONS
- SERVICE NOTES
- INDEX
Compaq Deskpro EP Series of Personal Computers 6-3
6.1.3 DMA
Hardware DMA System Function
DMA 0 Unused
DMA 1 Audio (Alternate = DMA 0 or 3)
DMA 2 Diskette Drive
DMA 3 ECP Parallel Port LPT1 (Default; Alternate = DMA 0)
DMA 4 DMA Controller Cascading (Not on ISA Bus)
DMA 5 Unused
DMA 6 Unused
DMA 7 Unused
6.1.4 I/O
I/O Address (Hex) System Function (Shipping Configuration)
000 - 00F DMA Controller # 1
010 - 01F Unused
020 - 03F Interrupt Controller # 1
040 - 043 Counter/Timer
044 - 05F Unused
060 Keyboard Controller
061 Port B
062 - 063 Unused
064 Keyboard Controller
065 - 06F Unused
070 - 071 NMI Enable/Real-Time Clock
072 - 077 CMOS Storage
078 - 07F Unused
080 - 08F DMA Page Registers
090 - 091 Unused
092 Port A
093 - 09F Unused
0A0 - 0BF Interrupt Controller # 2
0C0 - 0DF DMA Controller # 2
0E0 - 0EB Unused
0EC - 0ED 483 Configuration Index/Data
0EE - 0EF 483 Fast A20/Fast Reset
0F0 - 0F1 Co-Processor Busy Clear/Reset
0F2 - 0F3 Unused
0F4 - 0F5 483 CPU Speed Slow/Fast
0F6 - 0F8 Unused
0F9 483/PGL Configuration Lock
Continued