cs106132@umbc5.umbc.edu (cs106132) (05/26/91)
Hi, I found out that Int 2F, subfunc 13h is used to set the Int 13h address and get the original one from DOS. If I get it right, DOS device driver grabs the original ROM address and replaces it with its own handler. But there is a way to find it out using undocumented Int 2F, 13h. Something like this: DS:DX points to current handler to set AX = 13h Int 2F DS:DX now contains the original address store away DS:DX Int 2F again to set it back to what it was Does anyone have an idea what this is all about? Any pointers will be appreciated. Ted Lee
caster@jove.cs.pdx.edu (Brad J. Caster) (05/27/91)
In article <1991May26.064558.13108@umbc3.umbc.edu> cs106132@umbc5.umbc.edu (cs106132) writes: ... > DS:DX points to current handler to set > AX = 13h ^^^^^^^^ AH = 13h or AX = 13xxh > Int 2F > DS:DX now contains the original address > store away DS:DX > Int 2F again to set it back to what it was ... Warning! Not for the novice.