1000 REM SAVE"0:SYMLISTER",8
1010 REM * 21 FEB 87  -  J.A.SPENCER
1020 REM * INDENTS ALL LINES STARTING
1030 REM * WITH 6510 OPCODES
1040 REM * SYMASS MUST INSTALLED
1050 :
1060 IF PEEK(700)=76 THEN 1120
1070 :
1080 PRINT "** SYMASS NOT INSTALLED **"
1090 PRINT "LOAD/RUN SYMASS FIRST"
1100 END
1110 :
1120 PRINT "SYS 828 TO ENABLE"
1130 PRINT "SYS 831 TO RESTORE PREVIOUS LIST VECTOR"
1140 :
1150 SYS700
1160 *=$033C
1170 ;
1180 SPACES = $08   ; # SPACES TO INDENT
1190 SRCAD  = $5F   ; CODE ADDRESS
1200 AD     = $7A   ; CHR(null)T & SYMASS
1210 IQPLOP = $0306 ; STD LIST JMP VEC
1220 SYMPTR = $02BD ; SYMASS VECTOR
1230 REGLST = $A71A ; NORMAL LIST CODE
1240 OUTDO  = $AB47 ; PRINT CHAR
1250 FINDOP = $0000 ; DUMMY VALUE
1260 WORD   = $0000
1270 ;
1280 JMP VECSET ; ENABLE
1290 JMP LISDIS ; DISABLE
1300 ;
1310 ; ALTER THE LIST VECTOR (IQPLOP)
1320 VECSET = *
1330 LDA IQPLOP  ; PICK UP
1340 STA RGL+1    ; CURRENT
1350 LDA IQPLOP+1 ; 'LIST'
1360 STA RGL+2    ; VECTOR
1370 LDA #<LVEC   ; INSTALL NEW
1380 STA IQPLOP   ; 'LIST'
1390 LDA #>LVEC   ; VECTOR
1400 STA IQPLOP+1
1410 LDA SYMPTR   ; CALC ADDR OF
1420 CLC          ; 'FINDOP'
1430 ADC #$9D     ; ROUTINE
1440 STA OPFD+1
1450 LDA SYMPTR+1 ; & INSERT IN
1460 ADC #$03     ; CODE BELOW
1470 STA OPFD+2
1480 CLC
1490 LDA SYMPTR   ; CALC ADDR OF
1500 ADC #$FA     ; 'WORD'
1510 STA WRD+1    ; ROUTINE
1520 LDA SYMPTR+1 ; IN SYMASS
1530 ADC #$05
1540 STA WRD+2
1550 RTS
1560 ;
1570 ; NEW ROUTINE FOR LISTING
1580 LVEC CPY #$04 ; CHECK ONLY
1590 BEQ OPSRCH    ; 1ST WORD
1600 ;
1610 REG LDA (SRCAD),Y ; ON LINE
1620 ;
1630 RGL JMP REGLST
1640 ;
1650 OPSRCH  STY $49
1660 JSR CALCAD
1670 ;
1680 WRD JSR WORD ; GET LEN OF
1690 JSR CALCAD  ; WORD ($59)
1700 ;
1710 OPFD JSR FINDOP
1720 BCC JREG   ; NOT MNEMONIC
1730 ;
1740 LDX #SPACES
1750 ;
1760 CON2 LDA #$20   ; INSERT SPACES
1770 JSR OUTDO
1780 DEX
1790 BNE CON2
1800 ;
1810 JREG LDY $49    ; RESTORE Y REG
1820 BNE REG
1830 ;
1840 ; SUBROUTINE TO SET UP SEARCH
1850 ; ADDRESS 'AD' IN SYMASS
1860 CALCAD = *
1870 LDA $49    ; ADD .Y TO
1880 CLC        ; CURRENT
1890 ADC SRCAD  ; ADDR
1900 STA AD
1910 LDA #$00
1920 ADC SRCAD+1
1930 STA AD+1
1940 RTS
1950 ;
1960 ; SYS TO DISABLE LIST FORMATTER
1970 LISDIS = *
1980 LDA RGL+1   ; RESTORE LAST
1990 STA IQPLOP  ; VECTOR
2000 LDA RGL+2
2010 STA IQPLOP+1
2020 RTS
2030 ;
2040 .END