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4 Summary of the HP/Phoenix BIOS
BIOS Addresses
Using the
Setup
program:
•
IRQ3 can be made available by disabling serial ports 2 and 4.
•
IRQ4 can be made available by disabling serial ports 1 and 3.
•
IRQ5 can be made available by disabling the parallel port 2.
•
IRQ7 can be made available by disabling parallel ports 1 and 2.
•
IRQ12 can be made available by disabling the mouse interrupt.
None of the interrupt service routines (ISRs), for the above lines, directly
flush any of the cache memories.
PCI Interrupt Request Lines
PCI devices generate interrupt requests using up to four PCI interrupt
request lines (INTA#, INTB#, INTC#, and INTD#).
When a PCI device makes an interrupt request, the request is re-directed to
the system interrupt controller. The interrupt request will be re-directed to
one of the IRQ lines made available for PCI devices.
All PCI devices with interrupt transfer support will use and share INTA#.
A multiple-function PCI device may use several INT lines. These devices will
require more than one system interrupt request line.
IRQ (Interrupt Vector)
Interrupt Request Description
IRQ0(08h)
System Timer
IRQ1(09h)
Keyboard Controller
IRQ2(0Ah)
Slave IRQ
Cascade connection from INTC2 (Interrupt Controller 2)
IRQ8(70h)
Real Time Clock
IRQ9(71h)
Available for accessory board (ISA/PCI)
IRQ10(72h)
SoundBlaster3, or Available for accessory board (ISA/PCI)
IRQ11(73h)
Available for accessory board (ISA/PCI)
IRQ12(74h)
Mouse, or ISA accessory board
IRQ13(75h)
Co-processor
IRQ14(76h)
IDE, or ISA accessory board
IRQ15(77h)
2nd IDE or ISA/PCI accessory board
IRQ3(0Bh)
Serial Port 2, Serial Port 4, or ISA accessory board
IRQ4(0Ch)
Serial Port 1, Serial Port 3, or ISA accessory board
IRQ5(0Dh)
SoundBlaster1, Parallel Port 2, or ISA accessory board
IRQ6(0Eh)
Flexible Disk Controller
IRQ7(0Fh)
SoundBlaster2, Parallel Port 1, or ISA accessory board
