[Coco] 64K ROM to RAM programs - where did this one come from?
Allen Huffman
alsplace at pobox.com
Tue Dec 14 16:58:25 EST 2021
And from the July 1987 Rainbow article, the DRIVER program looked like this:
4000: 1A 50 ORCC #$50
4002: 8E 80 00 LDX #$8000
4005: 7F FF DE CLR $FFDE
4008: A6 84 LDA ,X
400A: 7F FF DF CLR $FFDF
400D: A7 84 STA ,X
400F: 30 01 LEAX $01,X
4011: 8C FF 00 CMPX #$FF00
4014: 26 EF BNE $4005
4016: 1C 9F ANDCC #$9F
4018: 39 RTS
It stopped at $FF00 (where I/O begins), and is similar to Frank Hogg’s except it did not use an ,X+ increment. Instead, it would load from X, store at X, then use LEAX to add one to X to move to the next location.
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