DOS ain't dead - BORLAND DPMI-16bit - a workaround for this issue

BORLAND DPMI-16bit - a workaround for this issue (Announce)

posted by Japheth , Germany (South), 16.08.2011, 03:37
(edited by Japheth on 16.08.2011, 03:50)

> I don't know if "unknown" is the word here. 16-bit pmode never strictly
> targeted beyond 286 (16 MB), did it?

Yes, but the Borland extender is not really "286 only", because then it would restrict itself to allocate 16 MB - or 15 MB. However, it tries to allocate almost 64MB (65535 kb).

My guess is: the Borland extender uses the 16-bit version of LGDT or LIDT, which works with 24-bit addresses only. If you can find the occurances of these instructions in the extender, a patch may be possible. However, the patch may be tricky, because the 32-bit versions of these instructions requires an additional byte (66h).

---
MS-DOS forever!

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Complete thread:

UIDE etc. (July 22) - Rugxulo, 25.07.2011, 21:26 (Announce)
- UIDE+jemm+VCPI - david, 28.07.2011, 13:34
  - UIDE+jemm+VCPI - Rugxulo, 28.07.2011, 22:38
- FYI: DEATH (of Jack) - DOS386, 29.07.2011, 09:20
  - FYI: Jack still alive - Japheth, 30.07.2011, 07:57
    - FYI: Jack still alive - DOS386, 30.07.2011, 16:12
  - BORLAND DPMI-16bit - david, 31.07.2011, 18:31
    - BORLAND DPMI-16bit - Japheth, 31.07.2011, 21:09
      - BORLAND DPMI-16bit - david, 02.08.2011, 17:10
        BORLAND DPMI-16bit - Rugxulo, 13.08.2011, 01:35
        BORLAND DPMI-16bit - bretjohn, 13.08.2011, 17:30
        BORLAND DPMI-16bit - Rugxulo, 14.08.2011, 00:13
        BORLAND DPMI-16bit - Laaca, 14.08.2011, 12:07
        BORLAND DPMI-16bit - Khusraw, 14.08.2011, 18:04
        BORLAND DPMI-16bit - Rugxulo, 14.08.2011, 18:36
        BORLAND DPMI-16bit - Laaca, 16.08.2011, 22:24
        BORLAND DPMI-16bit - bretjohn, 14.08.2011, 18:48
        BORLAND DPMI-16bit - a workaround for this issue - Japheth, 15.08.2011, 16:29
        BORLAND DPMI-16bit - a workaround for this issue - Rugxulo, 15.08.2011, 22:29
        BORLAND DPMI-16bit - a workaround for this issue - Japheth, 16.08.2011, 03:37
        BORLAND DPMI-16bit - a workaround for this issue - Rugxulo, 16.08.2011, 07:51