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Appendix B
Page 26
Blue Chip Technology Ltd.
01271014.doc
APPENDIX B
PC/XT/AT Port Map
Address
Address
000-01F
DMA Controller 1, 8237A-5
020-03F
Interrupt Controller 1, 8259A
040-05F
Timer, 8254
060-06F
Keyboard Controller, 8742; Control Port B
070-07F
RTC and CMOS RAM, NMI Mask (Write)
080-09F
DMA Page Register (Memory Mapper)
0A0-0BF
Interrupt Controller 2, 8259
0F0
Clear NPX (80287) Busy
0F1
Reset NPX, 80287
0F8-0FF
Numeric Processor Extension, 80287
1F0-1F8
Hard Disk Drive Controller
200-207
Reserved
278-27F
Reserved for Parallel Printer Port 2
2F8-2FF
Reserved for Serial Port 2
300-31F
Reserved
360-36F
Reserved