TIP: Click on subject to list as thread! ANSI
echo: 80xxx
to: SAM IZZO
from: PETER LOUWEN
date: 1998-01-07 23:06:00
subject: Re: Registers on entry

 -=> Quoting Sam Izzo to All <=-
 SI> Can anyone tell me if it's safe to assume that all registers are zero
 SI> on entry to a .COM program?
According to Ralf Brown, it's like this:
 .COM-format executables begin running with the following register values:
 AL = 00h if first  FCB has valid drive letter, FFh if not
 AH = 00h if second FCB has valid drive letter, FFh if not
 CS,DS,ES,SS = PSP segment
 SP = offset of last word available in first 64K segment
 (note: AX is always 0000h under DESQview)
Peter
... He who would pursue revenge should first dig two graves.
--- EBO-BBS Diemen - NL
---------------
* Origin: EBO-BBS Diemen (http://home.worldonline.nl/~biginski) (2:280/901)

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