Disk->frame buffer DMA?

Article View: comp.sys.sgi.hardware

Article #89

Back to comp.sys.sgi.hardware Previous Next

#89

From: Dave Wiltzius
Date: Tue, 12 Jan 1993 05:02

22 lines
1320 bytes

We are interested in retrieving raster images from disk (or a
RAM DISK type device) into the frame buffer.  Lets assume that
the frame buffer window exactly matches the raster image
dimensions on disk so no image processing is required.  Is this
possible without the raster image passing through the main
memory?

I would envision that this would be *similar* to the image file
being mapped into the process' address space and some bitblt
command (aka lrectwrite) would transfer the image to a window
in the frame buffer.  What I am asking for is the above, but
without the raster image (disk file) being paged into memory
but rather transferred (via DMA?) directly to the frame buffer.

If this is not available, any plans for somesuch?

Thanks.  Please reply via email.

  Dave Wiltzius
  Lawrence Livermore Nat'l Lab
  wiltzius@llnl.gov

Technical Details

Message-ID: <145784@lll-winken.LLNL.GOV>

Path:

arc1-ca.pugleaf.net!sparky!uunet!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!agate!ames!lll-winken!anduin!wiltzius

Show Full Headers

Complete Article Headers

Path: arc1-ca.pugleaf.net!sparky!uunet!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!agate!ames!lll-winken!anduin!wiltzius
From: wiltzius@anduin.ocf.llnl.gov (Dave Wiltzius)
Newsgroups: comp.sys.sgi.hardware
Subject: Disk->frame buffer DMA?
Message-ID: <145784@lll-winken.LLNL.GOV>
Date: 12 Jan 93 05:02:39 GMT
Sender: usenet@lll-winken.LLNL.GOV
Organization: Lawrence Livermore Nat'l Lab.
Lines: 22
Nntp-Posting-Host: anduin.ocf.llnl.gov