American Megatrends Super Voyager VLB-III, Руководство пользователя, Страница: 15 / 138

Super Voyager VLB-III ISA Motherboard User's Guide
9
Onboard I/O,
Continued
I/O Wait State Generation
The motherboard has an open bus structure, allowing multiple processors to share system resources,
including memory. The motherboard supports system memory refresh from channel processors.
I/O Address Space
The Super Voyager VLB-III motherboard uses I/O addresses 0100h through 03FFh for ISA-compatible I/O.
Seven DMA Channels
The motherboard has seven DMA channels. Any DMA channel can be set for 8 or 16-bit DMA device
sizes.
Fifteen Interrupt Levels
The NMI takes precedence over all 15 hardware interrupts.
Priority Label Typical Interrupt Source
1 IRQ 0 Interval Timer 1, Counter 0 OUT
2 IRQ 1 Keyboard
3-10 IRQ 2 Used internally for IRQ 8 through IRQ 15
3 IRQ 8 Real-Time-Clock
4 IRQ 9 Bus
5 IRQ 10 Bus
6 IRQ 11 Bus
7 IRQ 12 Onboard PS/2 Mouse or AT bus through a
jumper
8 IRQ 13 Coprocessor Error (internal)
9 IRQ 14 Bus (Hard disk drive or Local Bus IDE
controller)
10 IRQ 15 Bus
11 IRQ 3 Bus (Serial Port 2)
12 IRQ 4 Bus (Serial Port 1)
13 IRQ 5 Bus (Parallel Port 2)
14 IRQ 6 Bus and floppy disk controller
15 IRQ 7 Bus (Parallel Port 1)