Acrosser AR-B1320 - Manual (Page 12)

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2.6 INTERRUPT CONTROLLER
The ALI M6117C also provides two-cascaded 8259 Programmable Interrupt Controllers (PIC). They
accept requests from the peripherals, resolve priorities on pending interrupts in service, issue
interrupt requests to the CPU, and provide vectors which are used as acceptance indexed by the
CPU to determine which interrupt service routine should be executed.
The following is the system information of interrupts levels:
IRQ8 : Real time clock
IRQ9 : Rerouting to INT 0Ah from hardware IRQ2
IRQ10 : Spare
IRQ11 : Spare
IRQ12 : Spare
IRQ13 : Reserved for Math. coprocessor
IRQ14 : Hard disk adapter
IRQ15 : Spare
In Interrupt Level
NMI
CTRL1
IRQ 0
IRQ 1
IRQ 2
IRQ 3
IRQ 4
IRQ 5
IRQ 6
IRQ 7
CTRL2
Parity check
Description
Serial port 2
Serial port 1
Spare
Floppy disk
Parallel port
System timer interrupt from timer 8254
Keyboard output buffer full
Figure 2-1 Interrupt Controller
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