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Routines |
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Used by the routines at DrawGraphic_Mirrored and DrawGraphic_RotatedHalf.
Reverses the order of the bits in a byte.
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| ReverseBits | 39570 | PUSH BC | Stash BC on the stack. | |||||||||
| 39571 | LD B,8 | B=8 (the number of bits to reverse). | ||||||||||
| ReverseBits_Loop | 39573 | RLA | Rotate the top bit of A into the carry flag. | |||||||||
| 39574 | RR C | Rotate the carry flag into the top of C. | ||||||||||
| 39576 | DJNZ ReverseBits_Loop | Decrease the bit counter by one and loop back to ReverseBits_Loop until all eight bits have been reversed. | ||||||||||
| 39578 | LD A,C | Fetch the reversed byte. | ||||||||||
| 39579 | POP BC | Restore BC from the stack. | ||||||||||
| 39580 | RET | Return. | ||||||||||
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