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Routines |
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The address of this routine is found in the table of addresses. It is called indirectly via fp_calc_2.
This subroutine performs the binary operation 'X$ AND Y' and returns X$ if Y is non-zero and a null string otherwise.
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| str_no | 13613 | EX DE,HL | Point HL at Y, DE at X$. | |||||
| 13614 | CALL TEST_ZERO | Test whether Y is zero. | ||||||
| 13617 | EX DE,HL | Swap the pointers back. | ||||||
| 13618 | RET NC | Return with X$ as the 'last value' if Y was non-zero. | ||||||
| 13619 | PUSH DE | Save the pointer to the number. | ||||||
| 13620 | DEC DE | Point to the fifth byte of the string parameters, i.e. length-high. | ||||||
| 13621 | XOR A | Clear the A register. | ||||||
| 13622 | LD (DE),A | Length-high is now set to zero. | ||||||
| 13623 | DEC DE | Point to length-low. | ||||||
| 13624 | LD (DE),A | Length-low is now set to zero. | ||||||
| 13625 | POP DE | Restore the pointer. | ||||||
| 13626 | RET | Return with the string parameters being the 'last value'. | ||||||
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