B-2 APPENDIX B: SPECIFICATIONS
Configuration Options
This section describes the configuration options for the
3C689 adapter. The following options are available:
■ Ring Speed
■ I/O Base Address
■ MMIO Address Location
■ Shared RAM Page Size and Address Range
■ Interrupt Request Level
These options are described on the following pages.
Ring Speed
The 3C689 adapter operates at either 4 or 16 Mbps ring
speed and must match the speed of the token ring network.
The default is 16 Mbps.
I/O Base Address
The I/O base addresses allowed are Primary or Secondary.
The Primary default address is A20h. If a system resource
conflict continues, you may have to change the settings of
other adapters or options that are in your computer.
MMIO Address Location
There are 16 possible 8 KB blocks of PC memory that can be
assigned for accessing the MMIO address area of the 3C689
adapter. The factory default MMIO address is CC000. The 16
MMIO address locations are listed below, with the defaults in
bold.
C0000–C1FFF D0000–D1FFF
C2000–C3FFF D2000–D3FFF
C4000–C5FFF D4000–D5FFF
C6000–C7FFF D6000–D7FFF
C8000–C9FFF D8000–D9FFF
CA000–CBFFF DA000–DBFFF
CC000–CDFFF DC000–DDFFF
CE000–CFFFF DE000–DFFFF
