jlh@loral.UUCP (Physically Pffft) (09/28/88)
I need to display some data thats 256 X 80K on a PC using CGA mode. I want
to use the PC's screen in CGA mode to let the user see a 320 unit window
into the data, and use the arrow keys to scroll left and right to see
different parts of the waveform, which means I need some way to scroll the
current screen horizontally. If you think of it as a logic analyzer
display your not too far off. So, my questions:
1) Can you recommend some good books or articles for info on CGA internals?
2) Is there a public domain package, or maybe one we can buy, to do the
scrolling?
3) Anyone got any advice, or know of any pitfalls to look out for?
4) If I get to the hardware level and diddle bits myself instead of using
BIOS, then can I treat an EGA card in CGA mode identically to a CGA card?
5) Would it be faster to build an image in memory, then memcpy() parts of it
into video ram?
I should mention that I'm supposed to write this in C, but I think I'll end
up doing the actual scrolling part in assembly to get any kind of acceptable
speed out of it. And the whole project is supposed to be done in 3 weeks
so I've only got about 1 week to do the actual scrolling (thanks people, how
long have you know about this?).
Jim
--
Jim Harkins
Loral Instrumentation, San Diego
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