S-C DocuMentor — Applesoft
SAVE S.D52C
1010 *--------------------------------
1020 * READ A LINE, AND STRIP OFF SIGN BITS
1030 *--------------------------------
D52C- A2 80 1040 INLIN LDX #$80 NULL PROMPT
D52E- 86 33 1050 INLIN2 STX MON.PROMPT
D530- 20 6A FD 1060 JSR MON.GETLN
D533- E0 EF 1070 CPX #239 MAXIMUM LINE LENGTH
D535- 90 02 1080 BCC .1
D537- A2 EF 1090 LDX #239 TRUNCATE AT 239 CHARS
D539- A9 00 1100 .1 LDA #0 MARK END OF LINE WITH $00 BYTE
D53B- 9D 00 02 1110 STA INPUT.BUFFER,X
D53E- 8A 1120 TXA
D53F- F0 0B 1130 BEQ .3 NULL INPUT LINE
D541- BD FF 01 1140 .2 LDA INPUT.BUFFER-1,X DROP SIGN BITS
D544- 29 7F 1150 AND #$7F
D546- 9D FF 01 1160 STA INPUT.BUFFER-1,X
D549- CA 1170 DEX
D54A- D0 F5 1180 BNE .2
D54C- A9 00 1190 .3 LDA #0 (Y,X) POINTS AT BUFFER-1
D54E- A2 FF 1200 LDX #INPUT.BUFFER-1
D550- A0 01 1210 LDY /INPUT.BUFFER-1
D552- 60 1220 RTS
1230 *--------------------------------
D553- 20 0C FD 1240 INCHR JSR MON.RDKEY *** OUGHT TO BE "BIT $C010" ***
D556- 29 7F 1250 AND #$7F
D558- 60 1260 RTS
1270 *--------------------------------
1280 * TOKENIZE THE INPUT LINE
1290 *--------------------------------
1300 PARSE.INPUT.LINE
D559- A6 B8 1310 LDX TXTPTR INDEX INTO UNPARSED LINE
D55B- CA 1320 DEX PREPARE FOR INX AT "PARSE"
D55C- A0 04 1330 LDY #4 INDEX TO PARSED OUTPUT LINE
D55E- 84 13 1340 STY DATAFLG CLEAR SIGN-BIT OF DATAFLG
D560- 24 D6 1350 BIT LOCK IS THIS PROGRAM LOCKED?
D562- 10 08 1360 BPL PARSE NO, GO AHEAD AND PARSE THE LINE
D564- 68 1370 PLA YES, IGNORE INPUT AND "RUN"
D565- 68 1380 PLA THE PROGRAM
D566- 20 65 D6 1390 JSR SETPTRS CLEAR ALL VARIABLES
D569- 4C D2 D7 1400 JMP NEWSTT START RUNNING
1410 *--------------------------------
D56C- E8 1420 PARSE INX NEXT INPUT CHARACTER
D56D- BD 00 02 1430 .1 LDA INPUT.BUFFER,X
D570- 24 13 1440 BIT DATAFLG IN A "DATA" STATEMENT?
D572- 70 04 1450 BVS .2 YES (DATAFLG = $49)
D574- C9 20 1460 CMP #' ' IGNORE BLANKS
D576- F0 F4 1470 BEQ PARSE
D578- 85 0E 1480 .2 STA ENDCHR
D57A- C9 22 1490 CMP #'" START OF QUOTATION?
D57C- F0 74 1500 BEQ .13
D57E- 70 4D 1510 BVS .9 BRANCH IF IN "DATA" STATEMENT
D580- C9 3F 1520 CMP #'? SHORTHAND FOR "PRINT"?
D582- D0 04 1530 BNE .3 NO
D584- A9 BA 1540 LDA #TOKEN.PRINT YES, REPLACE WITH "PRINT" TOKEN
D586- D0 45 1550 BNE .9 ...ALWAYS
D588- C9 30 1560 .3 CMP #'0 IS IT A DIGIT, COLON, OR SEMI-COLON?
D58A- 90 04 1570 BCC .4 NO, PUNCTUATION !"#$%&'()*+,-./
D58C- C9 3C 1580 CMP #';'+1
D58E- 90 3D 1590 BCC .9 YES, NOT A TOKEN
1600 *--------------------------------
1610 * SEARCH TOKEN NAME TABLE FOR MATCH STARTING
1620 * WITH CURRENT CHAR FROM INPUT LINE
1630 *--------------------------------
D590- 84 AD 1640 .4 STY STRNG2 SAVE INDEX TO OUTPUT LINE
D592- A9 D0 1650 LDA #TOKEN.NAME.TABLE-$100
D594- 85 9D 1660 STA FAC MAKE PNTR FOR SEARCH
D596- A9 CF 1670 LDA /TOKEN.NAME.TABLE-$100
D598- 85 9E 1680 STA FAC+1
D59A- A0 00 1690 LDY #0 USE Y-REG WITH (FAC) TO ADDRESS TABLE
D59C- 84 0F 1700 STY TKN.CNTR HOLDS CURRENT TOKEN-$80
D59E- 88 1710 DEY PREPARE FOR "INY" A FEW LINES DOWN
D59F- 86 B8 1720 STX TXTPTR SAVE POSITION IN INPUT LINE
D5A1- CA 1730 DEX PREPARE FOR "INX" A FEW LINES DOWN
D5A2- C8 1740 .5 INY ADVANCE POINTER TO TOKEN TABLE
D5A3- D0 02 1750 BNE .6 Y=Y+1 IS ENOUGH
D5A5- E6 9E 1760 INC FAC+1 ALSO NEED TO BUMP THE PAGE
D5A7- E8 1770 .6 INX ADVANCE POINTER TO INPUT LINE
D5A8- BD 00 02 1780 .7 LDA INPUT.BUFFER,X NEXT CHAR FROM INPUT LINE
D5AB- C9 20 1790 CMP #' ' THIS CHAR A BLANK?
D5AD- F0 F8 1800 BEQ .6 YES, IGNORE ALL BLANKS
D5AF- 38 1810 SEC NO, COMPARE TO CHAR IN TABLE
D5B0- F1 9D 1820 SBC (FAC),Y SAME AS NEXT CHAR OF TOKEN NAME?
D5B2- F0 EE 1830 BEQ .5 YES, CONTINUE MATCHING
D5B4- C9 80 1840 CMP #$80 MAYBE; WAS IT SAME EXCEPT FOR BIT 7?
D5B6- D0 41 1850 BNE .14 NO, SKIP TO NEXT TOKEN
D5B8- 05 0F 1860 ORA TKN.CNTR YES, END OF TOKEN; GET TOKEN #
D5BA- C9 C5 1870 CMP #TOKEN.AT DID WE MATCH "AT"?
D5BC- D0 0D 1880 BNE .8 NO, SO NO AMBIGUITY
D5BE- BD 01 02 1890 LDA INPUT.BUFFER+1,X "AT" COULD BE "ATN" OR "A TO"
D5C1- C9 4E 1900 CMP #'N "ATN" HAS PRECEDENCE OVER "AT"
D5C3- F0 34 1910 BEQ .14 IT IS "ATN", FIND IT THE HARD WAY
D5C5- C9 4F 1920 CMP #'O "TO" HAS PRECEDENCE OVER "AT"
D5C7- F0 30 1930 BEQ .14 IT IS "A TO", FIN IT THE HARD WAY
D5C9- A9 C5 1940 LDA #TOKEN.AT NOT "ATN" OR "A TO", SO USE "AT"
1950 *--------------------------------
1960 * STORE CHARACTER OR TOKEN IN OUTPUT LINE
1970 *--------------------------------
D5CB- A4 AD 1980 .8 LDY STRNG2 GET INDEX TO OUTPUT LINE IN Y-REG
D5CD- E8 1990 .9 INX ADVANCE INPUT INDEX
D5CE- C8 2000 INY ADVANCE OUTPUT INDEX
D5CF- 99 FB 01 2010 STA INPUT.BUFFER-5,Y STORE CHAR OR TOKEN
D5D2- B9 FB 01 2020 LDA INPUT.BUFFER-5,Y TEST FOR EOL OR EOS
D5D5- F0 39 2030 BEQ .17 END OF LINE
D5D7- 38 2040 SEC
D5D8- E9 3A 2050 SBC #': END OF STATEMENT?
D5DA- F0 04 2060 BEQ .10 YES, CLEAR DATAFLG
D5DC- C9 49 2070 CMP #TOKEN.DATA-':' "DATA" TOKEN?
D5DE- D0 02 2080 BNE .11 NO, LEAVE DATAFLG ALONE
D5E0- 85 13 2090 .10 STA DATAFLG DATAFLG = 0 OR $83-$3A = $49
D5E2- 38 2100 .11 SEC IS IT A "REM" TOKEN?
D5E3- E9 78 2110 SBC #TOKEN.REM-':'
D5E5- D0 86 2120 BNE .1 NO, CONTINUE PARSING LINE
D5E7- 85 0E 2130 STA ENDCHR YES, CLEAR LITERAL FLAG
2140 *--------------------------------
2150 * HANDLE LITERAL (BETWEEN QUOTES) OR REMARK,
2160 * BY COPYING CHARS UP TO ENDCHR.
2170 *--------------------------------
D5E9- BD 00 02 2180 .12 LDA INPUT.BUFFER,X
D5EC- F0 DF 2190 BEQ .9 END OF LINE
D5EE- C5 0E 2200 CMP ENDCHR
D5F0- F0 DB 2210 BEQ .9 FOUND ENDCHR
D5F2- C8 2220 .13 INY NEXT OUTPUT CHAR
D5F3- 99 FB 01 2230 STA INPUT.BUFFER-5,Y
D5F6- E8 2240 INX NEXT INPUT CHAR
D5F7- D0 F0 2250 BNE .12 ...ALWAYS
2260 *--------------------------------
2270 * ADVANCE POINTER TO NEXT TOKEN NAME
2280 *--------------------------------
D5F9- A6 B8 2290 .14 LDX TXTPTR GET POINTER TO INPUT LINE IN X-REG
D5FB- E6 0F 2300 INC TKN.CNTR BUMP (TOKEN # - $80)
D5FD- B1 9D 2310 .15 LDA (FAC),Y SCAN THROUGH TABLE FOR BIT7 = 1
D5FF- C8 2320 INY NEXT TOKEN ONE BEYOND THAT
D600- D0 02 2330 BNE .16 ...USUALLY ENOUGH TO BUMP Y-REG
D602- E6 9E 2340 INC FAC+1 NEXT SET OF 256 TOKEN CHARS
D604- 0A 2350 .16 ASL SEE IF SIGN BIT SET ON CHAR
D605- 90 F6 2360 BCC .15 NO, MORE IN THIS NAME
D607- B1 9D 2370 LDA (FAC),Y YES, AT NEXT NAME. END OF TABLE?
D609- D0 9D 2380 BNE .7 NO, NOT END OF TABLE
D60B- BD 00 02 2390 LDA INPUT.BUFFER,X YES, SO NOT A KEYWORD
D60E- 10 BB 2400 BPL .8 ...ALWAYS, COPY CHAR AS IS
2410 *---END OF LINE------------------
D610- 99 FD 01 2420 .17 STA INPUT.BUFFER-3,Y STORE ANOTHER 00 ON END
D613- C6 B9 2430 DEC TXTPTR+1 SET TXTPTR = INPUT.BUFFER-1
D615- A9 FF 2440 LDA #INPUT.BUFFER-1
D617- 85 B8 2450 STA TXTPTR
D619- 60 2460 RTS
2470 *--------------------------------
2480 * SEARCH FOR LINE
2490 *
2500 * (LINNUM) = LINE # TO FIND
2510 * IF NOT FOUND: CARRY = 0
2520 * LOWTR POINTS AT NEXT LINE
2530 * IF FOUND: CARRY = 1
2540 * LOWTR POINTS AT LINE
2550 *--------------------------------
D61A- A5 67 2560 FNDLIN LDA TXTTAB SEARCH FROM BEGINNING OF PROGRAM
D61C- A6 68 2570 LDX TXTTAB+1
D61E- A0 01 2580 FL1 LDY #1 SEARCH FROM (X,A)
D620- 85 9B 2590 STA LOWTR
D622- 86 9C 2600 STX LOWTR+1
D624- B1 9B 2610 LDA (LOWTR),Y
D626- F0 1F 2620 BEQ .3 END OF PROGRAM, AND NOT FOUND
D628- C8 2630 INY
D629- C8 2640 INY
D62A- A5 51 2650 LDA LINNUM+1
D62C- D1 9B 2660 CMP (LOWTR),Y
D62E- 90 18 2670 BCC RTS.1 IF NOT FOUND
D630- F0 03 2680 BEQ .1
D632- 88 2690 DEY
D633- D0 09 2700 BNE .2
D635- A5 50 2710 .1 LDA LINNUM
D637- 88 2720 DEY
D638- D1 9B 2730 CMP (LOWTR),Y
D63A- 90 0C 2740 BCC RTS.1 PAST LINE, NOT FOUND
D63C- F0 0A 2750 BEQ RTS.1 IF FOUND
D63E- 88 2760 .2 DEY
D63F- B1 9B 2770 LDA (LOWTR),Y
D641- AA 2780 TAX
D642- 88 2790 DEY
D643- B1 9B 2800 LDA (LOWTR),Y
D645- B0 D7 2810 BCS FL1 ALWAYS
D647- 18 2820 .3 CLC RETURN CARRY = 0
D648- 60 2830 RTS.1 RTS
2840 *--------------------------------
2850 * "NEW" STATEMENT
2860 *--------------------------------
D649- D0 FD 2870 NEW BNE RTS.1 IGNORE IF MORE TO THE STATEMENT
D64B- A9 00 2880 SCRTCH LDA #0
D64D- 85 D6 2890 STA LOCK
D64F- A8 2900 TAY
D650- 91 67 2910 STA (TXTTAB),Y
D652- C8 2920 INY
D653- 91 67 2930 STA (TXTTAB),Y
D655- A5 67 2940 LDA TXTTAB
D657- 69 02 2950 ADC #2 (CARRY WASN'T CLEARED, SO "NEW" USUALLY
D659- 85 69 2960 STA VARTAB ADDS 3, WHEREAS "FP" ADDS 2.)
D65B- 85 AF 2970 STA PRGEND
D65D- A5 68 2980 LDA TXTTAB+1
D65F- 69 00 2990 ADC #0
D661- 85 6A 3000 STA VARTAB+1
D663- 85 B0 3010 STA PRGEND+1
3020 *--------------------------------
3030 SETPTRS
D665- 20 97 D6 3040 JSR STXTPT SET TXTPTR TO TXTTAB - 1
D668- A9 00 3050 LDA #0 (THIS COULD HAVE BEEN ".HS 2C")
3060 *--------------------------------
3070 * "CLEAR" STATEMENT
3080 *--------------------------------
D66A- D0 2A 3090 CLEAR BNE RTS.2 IGNORE IF NOT AT END OF STATEMENT
D66C- A5 73 3100 CLEARC LDA MEMSIZ CLEAR STRING AREA
D66E- A4 74 3110 LDY MEMSIZ+1
D670- 85 6F 3120 STA FRETOP
D672- 84 70 3130 STY FRETOP+1
D674- A5 69 3140 LDA VARTAB CLEAR ARRAY AREA
D676- A4 6A 3150 LDY VARTAB+1
D678- 85 6B 3160 STA ARYTAB
D67A- 84 6C 3170 STY ARYTAB+1
D67C- 85 6D 3180 STA STREND LOW END OF FREE SPACE
D67E- 84 6E 3190 STY STREND+1
D680- 20 49 D8 3200 JSR RESTORE SET "DATA" POINTER TO BEGINNING
3210 *--------------------------------
D683- A2 55 3220 STKINI LDX #TEMPST
D685- 86 52 3230 STX TEMPPT
D687- 68 3240 PLA SAVE RETURN ADDRESS
D688- A8 3250 TAY
D689- 68 3260 PLA
D68A- A2 F8 3270 LDX #$F8 START STACK AT $F8,
D68C- 9A 3280 TXS LEAVING ROOM FOR PARSING LINES
D68D- 48 3290 PHA RESTORE RETURN ADDRESS
D68E- 98 3300 TYA
D68F- 48 3310 PHA
D690- A9 00 3320 LDA #0
D692- 85 7A 3330 STA OLDTEXT+1
D694- 85 14 3340 STA SUBFLG
D696- 60 3350 RTS.2 RTS
3360 *--------------------------------
3370 * SET TXTPTR TO BEGINNING OF PROGRAM
3380 *--------------------------------
D697- 18 3390 STXTPT CLC TXTPTR = TXTTAB - 1
D698- A5 67 3400 LDA TXTTAB
D69A- 69 FF 3410 ADC #$FF
D69C- 85 B8 3420 STA TXTPTR
D69E- A5 68 3430 LDA TXTTAB+1
D6A0- 69 FF 3440 ADC #$FF
D6A2- 85 B9 3450 STA TXTPTR+1
D6A4- 60 3460 RTS
3470 *--------------------------------
3480 * "LIST" STATEMENT
3490 *--------------------------------
D6A5- 90 0A 3500 LIST BCC .1 NO LINE # SPECIFIED
D6A7- F0 08 3510 BEQ .1 ---DITTO---
D6A9- C9 C9 3520 CMP #TOKEN.MINUS IF DASH OR COMMA, START AT LINE 0
D6AB- F0 04 3530 BEQ .1 IS IS A DASH
D6AD- C9 2C 3540 CMP #', COMMA?
D6AF- D0 E5 3550 BNE RTS.2 NO, ERROR
D6B1- 20 0C DA 3560 .1 JSR LINGET CONVERT LINE NUMBER IF ANY
D6B4- 20 1A D6 3570 JSR FNDLIN POINT LOWTR TO 1ST LINE
D6B7- 20 B7 00 3580 JSR CHRGOT RANGE SPECIFIED?
D6BA- F0 10 3590 BEQ .3 NO
D6BC- C9 C9 3600 CMP #TOKEN.MINUS
D6BE- F0 04 3610 BEQ .2
D6C0- C9 2C 3620 CMP #',
D6C2- D0 84 3630 BNE RTS.1
D6C4- 20 B1 00 3640 .2 JSR CHRGET GET NEXT CHAR
D6C7- 20 0C DA 3650 JSR LINGET CONVERT SECOND LINE #
D6CA- D0 CA 3660 BNE RTS.2 BRANCH IF SYNTAX ERR
D6CC- 68 3670 .3 PLA POP RETURN ADRESS
D6CD- 68 3680 PLA (GET BACK BY "JMP NEWSTT")
D6CE- A5 50 3690 LDA LINNUM IF NO SECOND NUMBER, USE $FFFF
D6D0- 05 51 3700 ORA LINNUM+1
D6D2- D0 06 3710 BNE LIST.0 THERE WAS A SECOND NUMBER
D6D4- A9 FF 3720 LDA #$FF MAX END RANGE
D6D6- 85 50 3730 STA LINNUM
D6D8- 85 51 3740 STA LINNUM+1
D6DA- A0 01 3750 LIST.0 LDY #1
D6DC- B1 9B 3760 LDA (LOWTR),Y HIGH BYTE OF LINK
D6DE- F0 44 3770 BEQ LIST.3 END OF PROGRAM
D6E0- 20 58 D8 3780 JSR ISCNTC CHECK IF CONTROL-C HAS BEEN TYPED
D6E3- 20 FB DA 3790 JSR CRDO NO, PRINT <RETURN>
D6E6- C8 3800 INY
D6E7- B1 9B 3810 LDA (LOWTR),Y GET LINE #, COMPARE WITH END RANGE
D6E9- AA 3820 TAX
D6EA- C8 3830 INY
D6EB- B1 9B 3840 LDA (LOWTR),Y
D6ED- C5 51 3850 CMP LINNUM+1
D6EF- D0 04 3860 BNE .5
D6F1- E4 50 3870 CPX LINNUM
D6F3- F0 02 3880 BEQ .6 ON LAST LINE OF RANGE
D6F5- B0 2D 3890 .5 BCS LIST.3 FINISHED THE RANGE
3900 *---LIST ONE LINE----------------
D6F7- 84 85 3910 .6 STY FORPNT
D6F9- 20 24 ED 3920 JSR LINPRT PRINT LINE # FROM X,A
D6FC- A9 20 3930 LDA #' ' PRINT SPACE AFTER LINE #
D6FE- A4 85 3940 LIST.1 LDY FORPNT
D700- 29 7F 3950 AND #$7F
D702- 20 5C DB 3960 LIST.2 JSR OUTDO
D705- A5 24 3970 LDA MON.CH IF PAST COLUMN 33, START A NEW LINE
D707- C9 21 3980 CMP #33
D709- 90 07 3990 BCC .1 < 33
D70B- 20 FB DA 4000 JSR CRDO PRINT <RETURN>
D70E- A9 05 4010 LDA #5 AND TAB OVER 5
D710- 85 24 4020 STA MON.CH
D712- C8 4030 .1 INY
D713- B1 9B 4040 LDA (LOWTR),Y
D715- D0 1D 4050 BNE LIST.4 NOT END OF LINE YET
D717- A8 4060 TAY END OF LINE
D718- B1 9B 4070 LDA (LOWTR),Y GET LINK TO NEXT LINE
D71A- AA 4080 TAX
D71B- C8 4090 INY
D71C- B1 9B 4100 LDA (LOWTR),Y
D71E- 86 9B 4110 STX LOWTR POINT TO NEXT LINE
D720- 85 9C 4120 STA LOWTR+1
D722- D0 B6 4130 BNE LIST.0 BRANCH IF NOT END OF PROGRAM
D724- A9 0D 4140 LIST.3 LDA #$0D PRINT <RETURN>
D726- 20 5C DB 4150 JSR OUTDO
D729- 4C D2 D7 4160 JMP NEWSTT TO NEXT STATEMENT
4170 *--------------------------------
D72C- C8 4180 GETCHR INY PICK UP CHAR FROM TABLE
D72D- D0 02 4190 BNE .1
D72F- E6 9E 4200 INC FAC+1
D731- B1 9D 4210 .1 LDA (FAC),Y
D733- 60 4220 RTS
4230 *--------------------------------
D734- 10 CC 4240 LIST.4 BPL LIST.2 BRANCH IF NOT A TOKEN
D736- 38 4250 SEC
D737- E9 7F 4260 SBC #$7F CONVERT TOKEN TO INDEX
D739- AA 4270 TAX
D73A- 84 85 4280 STY FORPNT SAVE LINE POINTER
D73C- A0 D0 4290 LDY #TOKEN.NAME.TABLE-$100
D73E- 84 9D 4300 STY FAC POINT FAC TO TABLE
D740- A0 CF 4310 LDY /TOKEN.NAME.TABLE-$100
D742- 84 9E 4320 STY FAC+1
D744- A0 FF 4330 LDY #-1
D746- CA 4340 .1 DEX SKIP KEYWORDS UNTIL REACH THIS ONE
D747- F0 07 4350 BEQ .3
D749- 20 2C D7 4360 .2 JSR GETCHR BUMP Y, GET CHAR FROM TABLE
D74C- 10 FB 4370 BPL .2 NOT AT END OF KEYWORD YET
D74E- 30 F6 4380 BMI .1 END OF KEYWORD, ALWAYS BRANCHES
D750- A9 20 4390 .3 LDA #' ' FOUND THE RIGHT KEYWORD
D752- 20 5C DB 4400 JSR OUTDO PRINT LEADING SPACE
D755- 20 2C D7 4410 .4 JSR GETCHR PRINT THE KEYWORD
D758- 30 05 4420 BMI .5 LAST CHAR OF KEYWORD
D75A- 20 5C DB 4430 JSR OUTDO
D75D- D0 F6 4440 BNE .4 ...ALWAYS
D75F- 20 5C DB 4450 .5 JSR OUTDO PRINT LAST CHAR OF KEYWORD
D762- A9 20 4460 LDA #' ' PRINT TRAILING SPACE
D764- D0 98 4470 BNE LIST.1 ...ALWAYS, BACK TO ACTUAL LINE
S.D365