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SvarDOS / edrdos

Enhanced DR-DOS kernel and command interpreter ported to JWasm and OpenWatcom C
http://svardos.org/
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Make sure local_chars does not have to be pinned to a specific memory location #66

Open boeckmann opened 4 months ago

boeckmann commented 4 months ago

Code tries to pin it to 0600h, which it cannot. Code also mentiones that this is located at 061Bh in DOS 4. Should be checked by inspecting MS-DOS 2 and 4 source code / memory map.

ecm-pushbx commented 4 months ago

Screenshot_20240709-234751

In msbio.tls there is a variable at 61Bh. I presume this is the one we're looking for.

ecm-pushbx commented 4 months ago

Variable definition: https://hg.pushbx.org/ecm/msdos4/file/e58e166f626e/src/BIOS/MSBDATA.INC#l668

Uses in this file at the indicated spot and several more: https://hg.pushbx.org/ecm/msdos4/file/e58e166f626e/src/BIOS/MSCON.ASM#l70

Variable definition and some uses: https://hg.pushbx.org/ecm/edrdos/file/bda60c09a545/drbio/init.asm#l660

More uses: https://hg.pushbx.org/ecm/edrdos/file/bda60c09a545/drbio/console.asm#l134

In EDR-DOS there are two bytes used as content then flag. In MS-DOS the one single byte is used as both.