Date: Sat, 22 Apr 1995 19:02:47 -0500 (CDT)
From: Aaron Ucko <UCKO AT VAX1 DOT ROCKHURST DOT EDU>
Subject: Re: extended memory
To: ldoan1 AT osf1 DOT gmu DOT edu
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Organization: Rockhurst College; Kansas City, MO

>> How can I access the particular addresses of extended memory (above 1MB) ?
>> I know the first 1MB is mapped to 0xE0000000 in the program's address space
>> but how is it with above 1MB memory ?
>> I need to access the memory of DT2862 frame grabber which grabs images
>> into extended memory from address 0xA00000.
>> How compiler handles that memory ?
>> Please help !
>
>The entire 256M of memory is mapped to 0xe0000000 (unless you don't have 
>that much... :->). If you want to access 0xa00000, just use 0xe0a00000. 
>BTW, that will not work under DPMI, unless you do some assembly coding to 
>map the memory yourself.

I think only 16M of memory gets mapped to go32_conventional_memory_selector()
(sp?) [which returns 0xe0000000 if you aren't in DPMI, but a value which may
change from session to session otherwise].  No hand coding should be necessary.

--- Aaron Ucko (ucko AT vax1 DOT rockhurst DOT edu; finger for PGP public key) | httyp!
Geek code 2.1 [for explanation, finger hayden@ | `God's Laws' (Rudy Rucker,  
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