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be52fb1383
On the real machine, I ended up at some point getting a weird "bottom mirroring" issue. It turns out that it was because when I revamped my VDP flags in an earlier commit, I hadn't read the whole technical notes about register $02 and falsely thought that B0 was ignored. No it's not. When set, it mirrors the bottom 8 rows.
11 lines
427 B
Plaintext
11 lines
427 B
Plaintext
CREATE _idat
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0b00000100 C, 0x80 C, ( Bit 2: Select mode 4 )
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0b00000000 C, 0x81 C,
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0b00001111 C, 0x82 C, ( Name table: 0x3800, *B0 must be 1* )
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0b11111111 C, 0x85 C, ( Sprite table: 0x3f00 )
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0b11111111 C, 0x86 C, ( sprite use tiles from 0x2000 )
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0b11111111 C, 0x87 C, ( Border uses palette 0xf )
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0b00000000 C, 0x88 C, ( BG X scroll )
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0b00000000 C, 0x89 C, ( BG Y scroll )
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0b11111111 C, 0x8a C, ( Line counter (why have this?) )
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