Personal Computer User Manual
Table Of Contents
- Contents
- Safety Information
- Overview
- Chapter 1. Installing options
- Features
- Specifications
- Available options
- Tools required
- Handling static-sensitive devices
- Installing external options
- Removing the cover
- Locating components
- Identifying parts on the system board
- Installing memory
- Installing adapters
- Installing internal drives
- Physical security
- Changing the battery
- Replacing the cover and connecting the cables
- Erasing a lost or forgotten password (clearing CMOS)
- Chapter 2. Using the IBM Setup Utility program
- Appendix A. Updating System Programs
- Appendix B. Manual modem commands
- Appendix C. System address maps
- Appendix D. Interrupt request and direct memory access channel assignments
- Appendix E. Notices
- Index
Address (hex) Description Bits Byte pointer
00C4 Channel 5, memory address register 00 – 15 Yes
00C6 Channel 5, transfer count register 00 – 15 Yes
00C8 Channel 6, memory address register 00 – 15 Yes
00CA Channel 6, transfer count register 00 – 15 Yes
00CC Channel 7, memory address register 00 – 15 Yes
00CE Channel 7, transfer count register 00 – 15 Yes
00D0 Channels 4–7, read status/write command register 00 – 07
00D2 Channels 4–7, write request register 00 – 02
00D4 Channels 4–7, write single mask register bit 00 – 02
00D6 Channels 4–7, mode register (write) 00 – 07
00D8 Channels 4–7, clear byte pointer (write) N/A
00DA Channels 4–7, master clear (write)/temp (read) 00 – 07
00DC Channels 4–7, clear mask register (write) 00 – 03
00DE Channels 4–7, write all mask register bits 00 – 03
00DF Channels 5–7, 8- or 16-bit mode select 00 – 07
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