| Routines

06415: THE 'LN-FETCH' SUBROUTINE

Used by the routines at ED_DOWN and LIST. This subroutine is entered with the HL register pair addressing a system variable - S-TOP or E-PPC. The subroutine returns with the system variable holding the line number of the following line.
Input
HL | S-TOP or E-PPC
LN_FETCH | 06415 | LD E,(HL) | The line number held by the system variable is collected.
| 06416 | INC HL
| 06417 | LD D,(HL)
| 06418 | PUSH HL | The pointer is saved.
| 06419 | EX DE,HL | The line number is moved to the HL register pair and incremented.
| 06420 | INC HL
| 06421 | CALL LINE_ADDR | The address of the start of this line is found, or the next line if the actual line number is not being used.
| 06424 | CALL LINE_NO | The number of that line is fetched.
| 06427 | POP HL | The pointer to the system variable is restored.
This entry point is used by the routine at ED_UP.
LN_STORE | 06428 | BIT 5,(IY+55) | Return if in 'INPUT mode' (bit 5 of FLAGX set).
| 06432 | RET NZ
| 06433 | LD (HL),D | Otherwise proceed to enter the line number into the two locations of the system variable.
| 06434 | DEC HL
| 06435 | LD (HL),E
| 06436 | RET | Return when it has been done.