🚀 go-pugleaf

In article <Iaw_cB600VY6IMyqUW@andrew.cmu.edu> jc58+@andrew.cmu.edu (Johnny J. Chin) writes:
>First of all ... the hardware interrupt for the serial ports are 3 or 4, by
>default.
>
>COM1 - IRQ4 (hardware interrupt request #4)
>COM2 - IRQ3
>
>As for some other common ones:
>
>INT 0 - NMI (non-maskable interrupt) - usually due to memory parity error
>INT 1 - reserved
>INT 2 - used by many EGA/VGA cards (usually available on 8088)
>        cascading interrupt on 286/386/486 machines
>INT 3 - COM2:
>INT 4 - COM1:
>INT 5 - Hard Disk Controller on 8088 (available for LPT2: on 286/386/486)
>INT 6 - Floppy Controller
>INT 7 - LPT1:
>
>INT 14 - cascaded off INT 2 - Hard Disk Controller on 286/386/486.
>
>
>I hope this information helps ...

These are IRQ's, not INTS - ie, when COM1 needs service it DOES NOT issue
an int 3, it issues an INT 0BH. Note that IRQ interrupts start at int 08H
the timer vector. Based on this I think that INT 0 is not an IRQ but an INT
line on the CPU, otherwise, the timer would be vectored to NMI (which it isn't)

Steve


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