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20 lines
575 B
Plaintext
20 lines
575 B
Plaintext
;Atari 2600 Initialization Code - C02 Assembly Language File
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; From CLEAN_START macro by Andrew Davie
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; Standardised start-up code, clears stack, all TIA registers and RAM to 0
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; Sets stack pointer to $FF, and all registers to 0
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; Sets decimal mode off, sets interrupt flag (kind of un-necessary)
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; Use as very first section of code on boot (ie: at reset)
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; Code written to minimise total ROM usage - uses weird 6502 knowledge :)
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START: SEI
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CLD
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LDX #0
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TXA
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TAY
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STARTC: DEX
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TXS
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PHA
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BNE STARTC
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JMP MAIN
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