Re: Debugging APM - cat /proc/apm produces oops

From: Ondrej Zary
Date: Sun Jul 23 2006 - 10:40:48 EST

On Sunday 23 July 2006 16:30, Ondrej Zary wrote:
> I've tried calling the APM 0x530A function from DOS (real mode, int 15h)
> and single-stepping the BIOS APM code (using good old user-friendly Turbo
> Debugger). Noticed some OUTs to 0xB1 (or something like that), then some
> PCI accesses (0xCF8 and 0xCFC) and then IP ended in area of all zeros. When
> I step over the int 15h call, it works fine - returns correct info.

Sorry, this was my bad. It works fine even when single stepping. I've made a
mistake and stepped over the ending int 20h instruction of my .com program...

I'm probably going to write down complete sequence of instructions which get
executed during the call.

Ondrej Zary
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