Chapter 1 25DMA Channel Assignment
DMA Channel Function
DRQ0 Audio or FIR(optional)
DRQ1 ECP or Audio or FIR(option al)
DRQ2 Floppy
DRQ3 ECP or FIR(optional)
DRQ4 Not Used
DRQ5 Not used
DRQ6 Not used
DRQ7 Not used
I/O Address Map
I/O Address Function
000-00F DMA controller-1
020-021 Interr upt controller-1
040-043 Timer 1
060, 064 Keyboard controller 87 42 chip select
061 System speaker out
040B DMA controller-1
061 System speaker
070-071 Real-ti me clock and NMI mask
080-08F DMA page register
0A0-0A1 Interrupt controller- 2
0C0-0DF DMA controller-2
0F0-0FF Numeric data proc essor
120-13F
180-18F
Power management controller
170-177 2nd EIDE device (CD-ROM) select
1F0-1F7 1st EIDE device (hard drive) select
220-22F Audio
240-24F Audio(optional)
278-27F Parallel port 3
2E8-2EF COM4
2F8-2FF COM2 or FIR(optional)
378, 37A Para llel port 2