Hi!
26-Июл-2006 14:41 [EMAIL PROTECTED] (Michael Devore) wrote to
<freedos-devel@lists.sourceforge.net>:
>> > Well, heck, if I already to have to change some A20 behavior to get a few
>> > ancient programs to work with that idiotic EXEPACK 0FFFFh address-wrapping
>> > (assuming EXEPACK makes A20 calls),
>>*VERY* early PKLITE (~1992) versions had the same bug
>>AFAIK, it doesn't - it's older then the invention of HMA
[I miss this original letter, so I answer here]. HMA was invented
torether with 80286, and this happens long ago before 1992.
>>in fact, this shouldn't happen in freedos; exactly for this reason
>>the kernel disables A20 before beginning execution of any program, so
>>that the (potential) startup code gets executed with A20 disabled, and
>>gets only enabled with the first Int 21
MD> You are right again. Eric indicated I need to allow local A20 control, but
MD> as it turns out, that won't help. EXEPACK code simply doesn't call A20
MD> routines, so EMM386 cannot fix this problem. It never "sees" the wrap
MD> occurring. The situation has to be corrected within the kernel.
MD> So how do we agitate to restore the kernel to its original behavior? I've
"Restore"? You wish to say, that in some kernel version was disabled
dealing with A20 turning off/on around program execution?
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