From: jjed AT hotmail DOT com
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Physical address of linear memory (again)
Date: Thu, 19 Nov 1998 09:37:50 GMT
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References: <72q9v6$a8h$1 AT nnrp1 DOT dejanews DOT com> <72ubfv$5h6$1 AT latinum DOT dresearch DOT de>
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

In article <72ubfv$5h6$1 AT latinum DOT dresearch DOT de>,
  "Michael Beck" <beck AT dresearch DOT de> wrote:

> Sorry, I don't understand your question right. The VDMA-Services are for
> ISA-DMA only. It's main usage
> is for the case that in V86 mode the physical addresses did not always match
> the logical, so
> double buffering is needed. You cannot use them for accesing PCI
> memory.Neither ISA-DMA did work
> for memory-to-memory copy, nor it can access memory addresss higher that
> 16MB.

Actually I need to get the physical address of a buffer (allocated with
malloc in protected mode) so I can program the PCI card to put data in it.
The PCI card is a bus master can access all the memory but I have to use the
physical address to program it.

Best Regards,
James.

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