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18 lines
760 B
Plaintext
18 lines
760 B
Plaintext
Tiny GR 8
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8-byte Intro for Apple II, Lovebyte 2022
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by Deater / dSr
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You can't do much 6502 assembly in 8 bytes.
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This code takes advantage of the fact that on boot, Applesoft BASIC
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puts a short routine CHRGET in RAM at address $B1-$C8 that parses
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tokens. We can drop our code in the middle of there and re-use
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some of the branching infrastructure.
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What this code does is just read out memory, starting at $7800 and
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printing it to the screen, with lo-res mode enabled. This makes
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a pattern that depends on the default power up of the DRAM (white and black
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bars for many Apple II models). At the end it crashes through DOS3.3
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(the colored pattern) and then into the MMIO (soft-switch) area
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which leads to a switch to hi-res, some brief sound, then a crash.
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