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Routines |
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Works out how much of a span is in view. Purpose not yet known.
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| ClipSpan | C629 | LD H,$00 | H is 00. | |
| C62B | LD A,L | L moves into A. | ||
| C62C | SUB E | Subtract E. | ||
| C62D | JR C,ClipSpan_Skip | Jump to C63B if the carry flag is set. | ||
| C62F | LD H,A | A moves into H. | ||
| C630 | SUB B | Subtract B. | ||
| C631 | RET NC | Return if the carry flag is reset. | ||
| C632 | LD L,E | E moves into L. | ||
| C633 | NEG | Negate A. | ||
| C635 | LD B,A | A moves into B. | ||
| C636 | CP C | Compare A with C. | ||
| C637 | RET C | Return if the carry flag is set. | ||
| C638 | LD B,C | C moves into B. | ||
| ClipSpan_Loop | C639 | SCF | Set the carry flag. | |
| C63A | RET | Return. | ||
| ClipSpan_Skip | C63B | ADD A,C | Plus C. | |
| C63C | RET NC | Return if the carry flag is reset. | ||
| C63D | JR Z,ClipSpan_Skip2 | Jump to C644 if the zero flag is set. | ||
| C63F | CP B | Compare A with B. | ||
| C640 | JR NC,ClipSpan_Loop | Jump to C639 if the carry flag is reset. | ||
| C642 | LD B,A | A moves into B. | ||
| C643 | RET | Return. | ||
| ClipSpan_Skip2 | C644 | XOR A | Set A to zero. | |
| C645 | RET | Return. | ||
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