Compaq Deskpro 4000N - Desktop PC, Maintenance & Service Manual

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7-2 Specifications
Table 7-2
System Interrupts
Hardware IRQ System Function
IRQ 0 Timer Interrupt (Not on ISA Bus)
IRQ 1 Keyboard (Not on ISA Bus)
IRQ 2 Interrupt Controller Cascade (Not on ISA Bus)
IRQ 3 Unused
IRQ 4 Serial Port (COM 1)
IRQ 5 Unused
IRQ 6 Diskette Drive
IRQ 7 Parallel Port (LPT 1)
IRQ 8 Real-Time Clock (Not on ISA Bus)
IRQ 9 Unused
IRQ 10 Unused
IRQ 11 PCI Interrupt
IRQ 12 Mouse
IRQ 13 Coprocessor (Not on ISA Bus)
IRQ 14 IDE Interface Hard Drive
IRQ 15 CD-ROM
Table 7-3
System DMA
Hardware DMA System Function
DMA 0 Unused
DMA 1 Unused
DMA 2 Diskette Drive
DMA 3 ECP Parallel Port LPT1 (Default; Alternate = DMA 0)
DMA 4 DMA Controller Cascading (Not on ISA Bus)
DMA 5 Unused
DMA 6 Unused
DMA 7 Unused