From: "Carlos Giani_AEN2003 (M2003)" <DARKVALE AT pcc DOT tgm DOT ac DOT at>
Organization:  TGM / PCC
To: djgpp AT delorie DOT com
Date:          Thu, 18 Mar 1999 15:30:28 MET-1MDT
Subject:       Re: Addressing physical memory
X-mailer: Pegasus Mail v3.22
Message-ID: <AF11D811F5@pcc.tgm.ac.at>
Reply-To: djgpp AT delorie DOT com

> From:           "Peter S'heeren" <petersh AT pimc DOT be>
> Subject:        Addressing physical memory
> Date sent:      Thu, 18 Mar 1999 11:47:49 +0100
> Organization:   EUnet Belgium, Leuven, Belgium
> To:             djgpp AT delorie DOT com
> Send reply to:  djgpp AT delorie DOT com

> 
> Hi
> 
> I have a problem with accessing physical memory. I wanna do this: (1)
> allocate some physical memory pages (address isn't important, pages may
> be continguous), (2) determine their physical address, (3) pass these
> addresses to a bus-master capable PCI card that tries to read data from
> these addresses (experimental hardware).
> 
> The precise address of the pages isn't important because the PCI card
> can access the entire 4GB physical memory space. The pages should be
> mapped in linear memory space and their contents should not be swapped
> away.
> 
> Has someone faced this problem before and found a solution for it ?
> 
> Peter S'heeren
> 
> 
> 

Try to lock your memory. Have a look at the Allegro macros
(LOCK_VARIABLE etc.) for this.

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| Carlos Giani_AEN2003, PC-Club (M2003)               |
| TGM - Schule der Technik, Abteilung Elektronik      |
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