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chitselb / pettil

6502 Forth-83 dialect for the Commodore PET 2001
http://pettil.tumblr.com
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rlencode/rldecode rules #13

Closed chitselb closed 10 years ago

chitselb commented 10 years ago

repeat counts - x x 0 = 256 total; x x 1 is impossible; x x 2 is 2 total (do nothing)

chitselb commented 10 years ago

rlencode rewritten to conform to this rule used by mkpkt

chitselb commented 10 years ago

rlencode needs to stop when the output buffer fills. This is unlikely, but can be forced for testing by putting AABBAABBAABB (repeating pairs) to fill the screen.

if rlencode fails (negative compression efficiency) then the screen gets stored by CMOVE instead. Also if this happens, the $4000 bit (uncompressed?) will be set on the packet length/flags field.

chitselb commented 10 years ago

fixed