Re: Interrupts not being raised.
Brian Gerst (bgerst@quark.vpplus.com)
Fri, 12 Feb 1999 14:11:08 -0500
David Woodhouse wrote:
> How are interrupts handled on Intel UP machines? I always assumed that there
> was a single 'IRQ' line to the CPU, and the handler for that interrogated the
> PIC to find out which interrupt was raised. I can't find that code in the
> kernel though - it seems as if PIC interrupts are generating INT 0x20-0x2f
> directly. What am I missing?
IIRC, the PIC puts the IRQ number on the data bus when it asserts the
IRQ line. The cpu reads that and jumps to the appropriate
vector/descriptor.
--
Brian Gerst
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