| Spectrum ROM | Routines |
| Prev: 07427 | Up: Map |
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This subroutine is used to find occurrences of either DATA, DEF FN or NEXT.
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| LOOK_PROG | 07558 | LD A,(HL) | Fetch the present character. | ||||||||||
| 07559 | CP ":" | Jump forward if it is a ':', which will indicate there are more statements in the present line. | |||||||||||
| 07561 | JR Z,LOOK_P_2 | ||||||||||||
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Now a loop is entered to examine each further line in the program.
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| LOOK_P_1 | 07563 | INC HL | Fetch the high byte of the line number and return with carry set if there are no further lines in the program. | ||||||||||
| 07564 | LD A,(HL) | ||||||||||||
| 07565 | AND 192 | ||||||||||||
| 07567 | SCF | ||||||||||||
| 07568 | RET NZ | ||||||||||||
| 07569 | LD B,(HL) | The line number is fetched and passed to NEWPPC. | |||||||||||
| 07570 | INC HL | ||||||||||||
| 07571 | LD C,(HL) | ||||||||||||
| 07572 | LD (23618),BC | ||||||||||||
| 07576 | INC HL | Then the length is collected. | |||||||||||
| 07577 | LD C,(HL) | ||||||||||||
| 07578 | INC HL | ||||||||||||
| 07579 | LD B,(HL) | ||||||||||||
| 07580 | PUSH HL | The pointer is saved whilst the address of the end of the line is formed in the BC register pair. | |||||||||||
| 07581 | ADD HL,BC | ||||||||||||
| 07582 | LD B,H | ||||||||||||
| 07583 | LD C,L | ||||||||||||
| 07584 | POP HL | The pointer is restored. | |||||||||||
| 07585 | LD D,0 | Set the statement counter to zero. | |||||||||||
| LOOK_P_2 | 07587 | PUSH BC | The end-of-line pointer is saved whilst the statements of the line are examined. | ||||||||||
| 07588 | CALL EACH_STMT | ||||||||||||
| 07591 | POP BC | ||||||||||||
| 07592 | RET NC | Make a return if there was an 'occurrence'; otherwise consider the next line. | |||||||||||
| 07593 | JR LOOK_P_1 | ||||||||||||
| Prev: 07427 | Up: Map |