DOS ain't dead

MKeyB & MS SmartDrv (Developers)

posted by Japheth , Germany (South), 22.05.2024, 12:54

> Btw., on my keyboard "MKEYB GR" strangely doesn't translate key 0x56 (
> backslash-key on the US keyboard ) - although I can see that the key is
> supposed to be translated. Probably have to compile it on my own.

It turned out that Mkeyb and MS SmartDrv don't like each other. The root of the problem is that MKEYB's Int 15h handler expects the carry flag to be set, else it does nothing. If SmartDrv is loaded AFTER Mkeyb, it also installs an Int 15h handler, to catch Ctrl-Alt-Del. It doesn't care about the the carry flag, and the crucial code is:


cmp ax, 4F53h
jnz prev_handler


That also explains why it's just key 56h that isn't translated, the usual keys have scan codes < 53h.

The simplest fix is to load MKeyb AFTER MS SmartDrv.

---
MS-DOS forever!

Complete thread:

• Debug/X v2.50, JDeb386, 386SWAT, Keyboard.sys - Japheth, 13.05.2024, 13:26
  • Debug/X v2.50, JemmDbg, 386SWAT, Keyboard.sys - tom, 13.05.2024, 13:50
    • Debug/X v2.50, JemmDbg, 386SWAT, Keyboard.sys - Japheth, 17.05.2024, 18:44
      • MKeyB & MS SmartDrv - Japheth, 22.05.2024, 12:54
  • Debug/X v2.50, JemmDbg, 386SWAT, Keyboard.sys - bretjohn, 13.05.2024, 19:20
    • Debug/X v2.50, JemmDbg, 386SWAT, Keyboard.sys - Japheth, 14.05.2024, 08:44
      • Debug/X v2.50, JemmDbg, 386SWAT, Keyboard.sys - bretjohn, 14.05.2024, 16:04
  • Debug/X v2.50 & JDeb386 released - Japheth, 03.06.2024, 07:59