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Routines |
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Subtracts A from flag B, sticking at zero.
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| SubtractFromFlag | 69FE | CALL FlagAddress | Point at flag B. A is the amount to subtract. | |||||||
| 6A01 | LD ($5B94),A | |||||||||
| 6A04 | LD A,(HL) | The flag minus the amount, via the scratch byte. | ||||||||
| 6A05 | PUSH HL | |||||||||
| 6A06 | LD HL,$5B94 | |||||||||
| 6A09 | AND A | The result sticks at zero. | ||||||||
| 6A0A | SUB (HL) | |||||||||
| 6A0B | JR NC,SubtractFlag_Store | |||||||||
| 6A0D | XOR A | |||||||||
| SubtractFlag_Store | 6A0E | POP HL | Store the result. | |||||||
| 6A0F | LD (HL),A | |||||||||
| 6A10 | RET | Return. | ||||||||
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