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joncampbell123 / doslib

Hackipedia DOSLIB, a general collection of useful libraries for writing MS-DOS software
GNU Lesser General Public License v2.1
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hw/dos himemsys.c functions assume 32-bit registers, cannot run on 286 processors #34

Closed joncampbell123 closed 6 years ago

joncampbell123 commented 6 years ago

HIMEM.SYS was devised at a time when 286 or higher systems had extended memory.

Therefore it is inappropriate to use 32-bit 386 instructions to read/write CPU registers when talking to HIMEM.SYS.

It is only appropriate to use 32-bit registers when using extended functions designed for use with 386 or higher.

This issue makes it impossible to write and test HIMEM.SYS calls on 286 systems.

joncampbell123 commented 6 years ago

Fixed