Apple-2-SW
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apple2_hgr_packer
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Fix link, sector usage, and indentation

This commit is contained in:
Michaelangel007 2017-10-09 02:18:38 -07:00
parent 4cb6e13761
commit ee04be65bb
1 changed files with 6 additions and 4 deletions
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10
pack_unpack.s
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@ -1,7 +1,8 @@
; https://github.com/Michaelangel007/apple2_hgr_packer
; Michael Pohoreski
; github
;
; HGR Packer/Unpacker by removing/adding HGR screen holes
; Pack 8,192 bytes down to 8,192-512 = 7,680 = 30 sectors instead of 34 sectors
; Pack 8,192 bytes down to 8,192-512 = 7,680 = 30 sectors instead of 32 sectors
; Remove the "screen holes" by "sliding" remaining memory down over them
; Basically a glorified memcpy()
;
@ -162,8 +163,9 @@
; Last Packed Byte: $5DFF
; Each page of HGR memory has 6 scanlines
; First Half of Page ($78 bytes) = 3 scanlines
; Last Half of Page ($78 bytes) = 3 scanlines
; First Half of Page ($78 bytes) = 3 scanlines
; Last Half of Page ($78 bytes) = 3 scanlines
Row = $FB ; 6 scanlines/page processed per loop
Dst = $FC
Src = $FE