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svofski / vector06cc

Вектор-06ц в ПЛИС / Vector-06c in FPGA
http://svofski.github.io/vector06cc/
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MUSICIAN.ROM - scrolling jumps #29

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
Depending on the key being pressed, screen scroll position changes.

This happens because this program does not reset the value on the port 3
after keyboard scan is complete. Allegedly, this was not entirely necessary
because the 8255 is supposed to clear its output on mode change.

See this faq on Intel site: 
http://www.intel.com/design/archives/periphrl/docs/7190.htm

Original issue reported on code.google.com by svof...@gmail.com on 29 Jan 2008 at 9:30

GoogleCodeExporter commented 9 years ago 
Need to check with MikeJ perhaps??

Original comment by svof...@gmail.com on 29 Jan 2008 at 9:43