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Routines |
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Used by the routine at F047.
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The buffer at 7B00 has lookup entries that allow fast reversal of graphic data without having to recalculate it by hand.
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| 81E3 | LD A,(DE) | Get the first byte. | ||||||||
| 81E4 | EX AF,AF' | Swap A for the shadow copy. | ||||||||
| 81E5 | INC DE | Put the second byte in A. | ||||||||
| 81E6 | LD A,(DE) | |||||||||
| 81E7 | DEC DE | |||||||||
| 81E8 | LD L,A | Set the index to copy from the buffer. | ||||||||
| 81E9 | LD H,$7B | |||||||||
| 81EB | LDI | Do the copy. | ||||||||
| 81ED | EX AF,AF' | Swap A for the other instance. | ||||||||
| 81EE | LD H,$7B | Set the index to copy from the buffer. | ||||||||
| 81F0 | LD L,A | |||||||||
| 81F1 | LDI | Do the copy. | ||||||||
| 81F3 | JP PE,$81E3 | Loop while there is more to do. | ||||||||
| 81F6 | EXX | Swap all main registers and return. | ||||||||
| 81F7 | RET | |||||||||
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