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Routines |
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Used by the routine at ProcessMemoryEntry.
Adds the link word to its own address so the pointer reaches the linked record.
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| CalculatePointerOffset | 41484 | PUSH IX | Copy the record into the pointer, step back two bytes, and read the link. | |
| 41486 | POP HL | |||
| 41487 | DEC HL | |||
| 41488 | DEC HL | |||
| 41489 | LD E,(IX-2) | |||
| 41492 | LD D,(IX-1) | Add the link to its own address to reach the linked record, and read the record's flag byte. | ||
| 41495 | ADD HL,DE | |||
| 41496 | LD E,(IX+0) | |||
| 41499 | LD D,(IX+1) | Read the moved marker. | ||
| 41502 | LD A,D | Jump ahead to CalculatePointerOffset_Next if the pointer is not zero. | ||
| 41503 | OR E | |||
| 41504 | JR NZ,CalculatePointerOffset_Next | |||
| 41506 | OR %00000001 | Reset the zero flag. | ||
| 41508 | RET | Return. | ||
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Return unless the two pointers are the same distance apart.
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| CalculatePointerOffset_Next | 41509 | AND A | Return if the adjusted pointer does not match the link. | |
| 41510 | SBC HL,DE | |||
| 41512 | RET NZ | |||
| 41513 | LD L,(IX+0) | Read the link in this record and the field it points at. | ||
| 41516 | LD H,(IX+1) | |||
| 41519 | PUSH BC | |||
| 41520 | LD E,(HL) | |||
| 41521 | INC HL | Read the high byte of the link into D. | ||
| 41522 | LD D,(HL) | |||
| 41523 | INC HL | |||
| 41524 | LD C,(HL) | Read the following word into BC. | ||
| 41525 | INC HL | |||
| 41526 | LD B,(HL) | |||
| 41527 | LD L,(IX-2) | Read the low byte saved ahead of this record. | ||
| 41530 | LD H,(IX-1) | Add DE to the saved pointer and store the low byte. | ||
| 41533 | ADD HL,DE | |||
| 41534 | LD (IX-2),L | |||
| 41537 | LD (IX-1),H | Store the high byte of the pointer in the previous record. | ||
| 41540 | LD (IX+0),C | Store the record's flag byte and store the moved marker. | ||
| 41543 | LD (IX+1),B | |||
| 41546 | POP BC | |||
| 41547 | XOR A | Clear A. | ||
| 41548 | RET | Return. | ||
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