[ASM] Get an address by line...

[XavSnap]

HI,
It's a little routine to retrieve the first REM address in a specific line…

Code: Select all

LINE_ADDR .equ $09D8 ; ZX81 ROM ROUTINE
RAM_SPARE2 .equ $407B ; TEMP LINE BUFFER

.org 16514 ; or somethings else
.dw $7676 ; hide me
main:
	LD HL,(RAM_SPARE2) ; BASIC LINE BUFFER (16507)
	CALL LINE_ADDR ; [LINE-ADDR]
	LD BC,$0005
	ADD HL,BC
	LD B,H
	LD C,L
	RET
.end

Basic demo:
1000 > Get ADD value from LINE address L=LINE (+ 5: HEADER+REM token).
2000 > Display the REM line.

Code: Select all

     0  REM [HEX:\
76,76,2A,7B,40,CD,D8,09,\
01,05,00,09,44,4D,C9 ]

# REM HELLO
     6  REM [HEX:\
2D,2A,31,31,34 ]

# REM WORLD
     8  REM [HEX:\
3C,34,37,31,29 ]

    10 LET L=6
    20 GOSUB 1E3
    30 PRINT ADD
    40 GOSUB 2E3
    50 PRINT 
    60 LET L=8
    70 GOSUB 1E3
    80 PRINT ADD
    90 GOSUB 2E3
    95 PRINT
   100 LIST 6
  1000 POKE 16508,INT (L/256)
  1100 POKE 16507,L-256*PEEK 16508
  1200 LET ADD=USR 16516
  1300 RETURN 
  2000 FOR A=ADD TO 5E4
  2200 PRINT (CHR$ PEEK A) AND PEEK A<>118;
  2300 IF PEEK A<>118 THEN NEXT A
  2400 RETURN 

GetLine.zip

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GETLINE.P

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[Moggy]

Thanks for this very useful at the moment for me.