where [BITS 32] directive?
in [ASM]
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From: Frank Kotler on 14 Aug 2007 08:46 opexoc(a)gmail.com wrote: .... > Another question: Is it really necessary to enable A20 line to enter > PM? If you want to access "odd megabytes", yeah. > Some tutorials write that it is needed, but others not. For example > there: > > http://www.osdever.net/tutorials/brunmar/tutorial_02.php > > The author doesn't do this ( maybe for simplicity ) Yeah, he only accesses the first (zeroth - even) megabyte of memory, so probably left it out for simplicity. Setting a20 on "some" machine is simple enough, code that will run on "any" machine gets more complicated. I think I've spotted a couple typos in that tut. In the text, he loads ss and ds with 8 - his code descriptor. In the downloaded source, he loads 'em with 10h, his data descriptor, which is correct. And the monochrome screen is at B0000h, not B80000h, if you care... Best, Frank
From: Herbert Kleebauer on 14 Aug 2007 11:01 Frank Kotler wrote: > And the > monochrome screen is at B0000h, not B80000h, if you care... As far I remember, it's neither B0000h nor B80000. DOS programming must be really dead when such essential values aren't correctly remembered.
From: Frank Kotler on 14 Aug 2007 11:08 Herbert Kleebauer wrote: > Frank Kotler wrote: > > >>And the >>monochrome screen is at B0000h, not B80000h, if you care... > > > As far I remember, it's neither B0000h nor B80000. DOS programming > must be really dead when such essential values aren't correctly > remembered. Okay, refresh my memory... Best, Frank
From: CodeMonk on 14 Aug 2007 11:13 Frank Kotler wrote: > Herbert Kleebauer wrote: >> Frank Kotler wrote: >> >> >>> And the >>> monochrome screen is at B0000h, not B80000h, if you care... >> >> >> As far I remember, it's neither B0000h nor B80000. DOS programming >> must be really dead when such essential values aren't correctly >> remembered. > > Okay, refresh my memory... > > Best, > Frank > Both values contained an extra zero, but no big deal - it's like 'mispelling' a word during an Instant Messaging session, they know what you mean. - Scott
From: Frank Kotler on 14 Aug 2007 11:26
CodeMonk wrote: > Frank Kotler wrote: > >> Herbert Kleebauer wrote: >> >>> Frank Kotler wrote: >>> >>> >>>> And the >>>> monochrome screen is at B0000h, not B80000h, if you care... >>> >>> >>> >>> As far I remember, it's neither B0000h nor B80000. DOS programming >>> must be really dead when such essential values aren't correctly >>> remembered. >> >> >> Okay, refresh my memory... >> >> Best, >> Frank >> > > Both values contained an extra zero, but no big deal - it's like > 'mispelling' a word during an Instant Messaging session, they know what > you mean. If I'da meant "B000:0000" I would've said so. Are you guys telling me the tut is correct? Best, Frank |