accessing more than 64k of video memory

This is a discussion on accessing more than 64k of video memory within the C Programming forums, part of the General Programming Boards category; In c++ class we use dos (no dpmi) borland compilers and use bgi stuff if we need to do graphics. ...

  1. #1
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    accessing more than 64k of video memory

    In c++ class we use dos (no dpmi) borland compilers and use bgi stuff if we need to do graphics. But there is this graphics library that some kid made a while back that the teacher let me use. The graphics library can do **** like 640x480x256 and 1024x768x256. Im assuming the kid wrote it in asm but How did he access that much video memory. All I can access is 64k. Any ideas how he did this?

    thanks

  2. #2
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    It's called bank switching - you set up your 64K window to overlay some part of a larger area of video memory.

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