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Routines |
| Prev: B252 | Up: Map | Next: B29F |
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Multiplies A by 4, returning the result in BC.
Used by the routines at transition and door_in_range.
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| multiply_by_4 | B295 | LD B,$00 | Initialise high byte of result to zero | |||||||||
| B297 | ADD A,A | Double input value | ||||||||||
| B298 | RL B | Shift carry out into high byte | ||||||||||
| B29A | ADD A,A | Double input value | ||||||||||
| B29B | RL B | Shift carry out into high byte | ||||||||||
| B29D | LD C,A | BC is the multiplied value | ||||||||||
| B29E | RET | Return | ||||||||||
| Prev: B252 | Up: Map | Next: B29F |