Xref: utzoo comp.binaries.ibm.pc.d:12538 comp.sys.ibm.pc:54676 Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!maverick.ksu.ksu.edu!ux1.cso.uiuc.edu!phil From: phil@ux1.cso.uiuc.edu (Phil Howard KA9WGN) Newsgroups: comp.binaries.ibm.pc.d,comp.sys.ibm.pc Subject: Re: Diamond Speedstar SVGA Questions Message-ID: <1991Feb19.235444.1055@ux1.cso.uiuc.edu> Date: 19 Feb 91 23:54:44 GMT Distribution: usa Organization: University of Illinois at Urbana Lines: 29 Based on replies from a previous query I made about the Diamond Speedstar I have learned that the extended VGA modes are done in many different ways on different chip sets. Different boards of the same chip set should be compatible at the register level. They might be incompatible at higher mode levels based on differences in the video BIOS code. I am not surprised that a software package that does not support a particular board or chip set cannot correct determine how much memory it has. Where it has to look or what it has to do to find out could, and likely would, vary between these boards. The only thing to do is to urge the software vendor to support the board. I suppose one way of support is to write graphics programs that make direct use of MSW drivers. Then you can just plug in the drivers and go from there. The fractint graphics package supports a large number of different boards and chip sets. That should give you an idea of the scope of the problem. It would be nice if a standardized set of efficient graphics functions could be designed (not necessary at high levels like "draw a circle") as an interface standard so that drivers between this standard and the many SVGA standards could be handled. This would be similar to the FTP Software approach to interfacing ethernet boards. But I don't know if this can possibly be done as fast as direct register/memory access specifically optimized to one board. -- --Phil Howard, KA9WGN-- | Individual CHOICE is fundamental to a free society | no matter what the particular issue is all about.