Specifications

Appendix A: Chip Set & I/O Map
A A
A-3
Port A
I/O Addr Functional group Usage
092 Port A Fast A20 and reset control
EXM Configuration
I/O Addr Functional group Usage
096 EXM Config EXM slot register (part of the
subplane)
Second Interrupt Controller:
VLSI 82C486 emulating 8259 of PC/AT
I/O Addr Functional group Usage
0A0 Interrupt controller 2 Port 0
0A1 Port 1
Second (16-bit) DMA Controller:
VLSI 82C486 emulating 8237 of PC/AT
I/O Addr Functional group Usage
0C0 DMA Channel 4 address
0C2 Channel 4 count
0C4 Channel 5 address
0C6 Channel 5 count
0C8 Channel 6 address
0CA Channel 6 count
0CC Channel 7 address
0CE Channel 7 count
0D0 Command/status
0D2 DMA request
0D4 Command register (R)
Single-bit DMA req mask(W)
0D6 Mode
0D8 Set byte pointer (R)
Clear byte pointer (W)
0DA Temporary register (R)
Master clear (W)
0DC Clear mode reg counter (R)
Clear all DMA req mask (W)
0DE All DMA request mask
0EC 82C486 index register
0ED 82C486 data register
Coprocessor Interface:
For the EPC-8 DX, DX replaces the 80287 of PC/AT
I/O Addr Functional group Usage
0F0 Coprocessor Clear coprocessor busy
0F1 Reset coprocessor
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com