TMC MI5VP4, User Manual

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Chapter 3 Hardware Description
10 MI5VP4 User’s Manual
3.8 Interrupt Request (IRQ) Lines
There is a total of 15 IRQ lines available on the motherboard. Peripheral
devices use an interrupt request to notify the CPU for the service
required. The following table shows the IRQ lines used by the devices on
the motherboard:
Level Function
IRQ0
System Timer Output
IRQ1 Keyboard
IRQ2 Interrupt Cascade
IRQ8 Real Time Clock
IRQ9 Software Redirected to Int 0Ah
IRQ10 Reserved
IRQ11 Reserved
IRQ12 Reserved
IRQ13 Co-Processor
IRQ14 Primary IDE
IRQ15 Secondary IDE
IRQ3 Interrupt
IRQ4 Serial Port #1
IRQ5 Interrupt
IRQ6 Floppy Disk Controller
IRQ7 Parallel Port #1
3.9 Onboard PCI-IDE
The VIA VT82C686A chip built-in’s PCI-IDE controller supports PIO
mode 3/4 and bus mastering Ultra DMA 33/66. The peak transfer rate of
PIO mode 3/4 can be as high as 17MB/sec. Using HDDs that support
Ultra DMA66, the peak transfer rate can reach 66MB/sec. There are two
IDE connectors - primary IDE and secondary IDE. With two devices per
connector, up to four IDE devices can be supported.
3.10 DMA Channels
There are seven DMA channels available on the motherboard; only
DMA2 is used by the floppy controller. In the case that ECP mode on the
parallel port is utilized, DMA1 or DMA3 will be used.