10 REM Generate an RFS image
   20 DIM block% 18
   30 DIM name% &10
   40 DIM crc% 128
   50 oswc=&FFEE:osnl=&FFE7:osas=&FFE3
   60 osfi=&FFDD:osgbpb=&FFD1
   70 tL%=&F2:tH%=&F3:vL%=&E8:vH%=&E9
   80 length%=name%:REM Dual purpose!
   90 REM Memory for oscall blocks,crc calculator & some zp pointer addresses
  100 :
  110 MODE7:PRINT"RFS image generator"'
  120 PRINTTAB(0,2);"ROM size is & 000 bytes":VDU31,13,2:romsize%=GET-48
  130 IFromsize%<>1 ANDromsize%<>2 ANDromsize%<>4 THENGOTO120 ELSEPRINTTAB(13,2);romsize%:romsize%=romsize%*&1000
  140 DIM image% romsize%
  150 :
  160 INPUT"Copyright string (C)"copy$:copy$="(C)"+copy$
  170 INPUT"Today's date in DDMMYY format: "title%:title$="RFS id:"+STR$~title%
  180 :
  190 VDU28,0,20,39,6:REM Text window
  200 :
  210 PRINT"Help text to be shown by *HELP RFS"'"(Upto 255 bytes long)"'"(Press Escape when finished)"'
  220 help$="":ONERRORGOTO280
  230 REPEAT:key%=GET
  240 IFLEN(help$)<255 THENVDUkey% ELSEVDU7
  250 IF(key%>31 ANDkey%<127)ORkey%=13 THENhelp$=help$+CHR$key%
  260 IF(key%=127 ORkey%=8)ANDLENhelp$>0 THENhelp$=LEFT$(help$,LENhelp$-1):REM Delete function 
  261 IFkey%=13 THENVDU10:REM Force LF 
  270 UNTILLENhelp$=255
  280 PRINT:ONERROROFF
  290 IFASC(RIGHT$(help$,1))<>13 ANDLEN(help$)<255 THENhelp$=help$+CHR$13:REM Always end on a CRLF
  300 :
  310 PROCassm:F=0:CLS:REM Make the header and set the file handle to null
  320 :
  330 REPEAT
  340 CLOSE#F:INPUT"Filename to add: "source$
  350 IFLEN(source$)=0 THENGOTO560
  360 INPUT"Write to RFS as: "dest$
  370 IFLEN(dest$)=0 THENPRINT'"Bad filename":F=0:GOTO340
  380 PRINT"Lock file (Y/N)?";
  390 REPEAT:key%=GET AND&DF:UNTILkey%=ASC"N" ORkey%=ASC"Y"
  400 protect%=key% AND1:PRINT;" ";CHR$(key%):REM Results in a 1 for 'Y' and 0 for 'N' and show results
  410 F=OPENINsource$
  420 IFF=0 THENPRINT'"File not found":GOTO340
  430 lof%=EXT#F:chunk%=0:REM Keep copy of EXT#F & reset chunk number
  440 IFlof%=0 THENPRINT'"File contains no data":GOTO340
  450 :
  460 header=21+LEN(dest$):REM That's how long a header block is
  470 top=((lof% MOD256)*(1-SGN(lof% DIV256)))+(256*(SGN(lof% DIV256)))+header+2:REM There's always a top bit,but its length is 1<len<257
  480 middle=259*((lof% DIV256)-2+(SGN(lof% MOD256)))*SGN(lof% DIV513):REM Middle bits are only enabled if lof% > 512
  490 bottom=((lof% MOD256)+(256*(1-SGN(lof% MOD256)))+header+2)*SGN(lof% DIV257):REM Bottom bits only occur if lof%>256 and can be of length 1<len<257
  500 IF(next%+top+middle+bottom)>(&8000+romsize%) THENPRINT'"File too large to add":GOTO340
  510 :
  520 next%=next%+top+middle+bottom:REM Work out where the next will start
  530 PROCosfile:REM Get attributes
  540 REPEAT:UNTILFNnextblock=FALSE
  550 :
  560 UNTILLENsource$=0
  570 :
  580 CLS:PRINT"Saving as 'OUTPUT'"
  590 ?eoi%=ASC"+":REM End of ROM marker is a plus
  600 OSCLI("SAVE OUTPUT "+STR$~(image%)+" +"+STR$~(romsize%)+" FFE7 8000")
  610 END
  620 :
  630 DEFPROCassm
  640 FORX=4 TO6 STEP2
  650 P%=&8000:O%=image%
  660 [OPTX
  670 EQUB0:EQUB0:EQUB0
  680 JMPserv
  690 EQUB&82:EQUBcopy MOD256:EQUB1
  700 .title
  710 EQUStitle$
  720 .copy
  730 EQUB0:EQUScopy$:EQUB0
  740 :
  750 .serv
  760 PHA:TYA:PHA:TSX:LDA&102,X:LDX#255:\Call details saved on stack
  770 .call
  780 INX:CMPhlpT,X:BEQmine:CPXhlpN:BEQrest:BNEcall
  790 .mine
  800 LDAhlpH,X:PHA:\Use the stack then  RTS to store the jump addr
  810 LDAhlpL,X:PHA:RTS
  820 :
  830 .mosquery
  840 TYA:EOR#15:\Perform 15-y
  850 CMP&F4:BCCrest
  860 LDX#next% MOD256:STX&F6
  870 LDY#next% DIV256:STY&F7
  880 LDA&F4:EOR#15:STA&F5
  890 :
  900 .dest
  910 PLA:PLA:LDA#0:RTS
  920 .rest
  930 PLA:TAY:PLA:RTS
  940 :
  950 .getbyte
  960 LDA&F5:EOR#15:\Perform reverse of 15-y
  970 CMP&F4:BNErest
  980 LDY#0:LDA(&F6),Y:TAY
  990 INC&F6:BNEdest:\Leave with Y containing the byte read
 1000 INC&F7:JMPdest
 1010 :
 1020 .help
 1030 LDA(tL%),Y:CMP#13:BNEextendhelp
 1040 .plainhelp
 1050 JSRhelpgeneric:JMPrest
 1060 .helpgeneric
 1070 JSRosnl:LDX#title MOD256:LDY#title DIV256:JSRprint:JMPosnl:\Show title with space top and bottom
 1080 .extendhelp
 1090 LDX#255:DEY:\Ready for INX,INY
 1100 .compare
 1110 INX:INY:LDA(tL%),Y:AND#&DF:CMPname,X:BEQcompare:\Make upper case and check against 'name'
 1120 LDAname,X:BPLrest:\Get mismatched byte
 1130 .rfstyped
 1140 JSRhelpgeneric
 1150 LDX#helptext MOD256:LDY#helptext DIV256:JSRprint:JMPrest:\Show extended help text
 1160 :
 1170 .print
 1180 STXvL%:STYvH%:LDY#255
 1190 .getchr
 1200 INY:LDA(vL%),Y:JSRosas:CMP#0:BNEgetchr:RTS:\Print out until a 0 is found
 1210 :
 1220 .hlpN
 1230 EQUB hlpL-hlpT-1:\Number of calls being watched for
 1240 .hlpT
 1250 EQUB14:EQUB13:EQUB9
 1260 .hlpL
 1270 EQUB(getbyte-1)MOD256
 1280 EQUB(mosquery-1)MOD256
 1290 EQUB(help-1)MOD256
 1300 .hlpH
 1310 EQUB(getbyte-1)DIV256
 1320 EQUB(mosquery-1)DIV256
 1330 EQUB(help-1)DIV256
 1340 .name
 1350 EQUS"RFS"+CHR$255
 1360 .helptext
 1370 EQUShelp$:EQUB0
 1380 .next%
 1390 ]
 1400 NEXT:eoi%=O%
 1410 :
 1420 FORX=0TO2STEP2
 1430 P%=crc%
 1440 [OPTX
 1450 .calccrc
 1460 LDA#0:STAcrcH:STAcrcL:TAY
 1470 .next
 1480 LDAcrcH:EOR(vL%),Y:STAcrcH
 1490 LDX#8
 1500 .again
 1510 LDAcrcH:ROLA:BCCover
 1520 LDAcrcH:EOR#8:STAcrcH
 1530 LDAcrcL:EOR#16:STAcrcL
 1540 .over
 1550 ROLcrcL:ROLcrcH:DEX:BNEagain
 1560 INY
 1570 CPYlength%:BNEnext
 1580 LDXcrcH:LDYcrcL:RTS
 1590 .crcL
 1600 EQUB0
 1610 .crcH
 1620 EQUB0
 1630 ]
 1640 NEXT
 1650 ENDPROC
 1660 :
 1670 DEFFNnextblock
 1680 IFchunk%=0 ANDlof%>256 THENPROCmakeblock("FIRST"):chunk%=chunk%+1:=TRUE
 1690 IFchunk%=0 ANDlof%<=256 THENPROCmakeblock("LAST"):=FALSE
 1700 IF(lof%-PTR#F)>256 THENPROCmakeblock("MIDDLE"):chunk%=chunk%+1:=TRUE
 1710 PROCmakeblock("LAST"):=FALSE
 1720 :
 1730 DEFPROCosfile
 1740 $name%=source$:?(name%+LEN(source$))=13:REM Build name block
 1750 P%=block%
 1760 [OPT2
 1770 EQUBname% MOD256:EQUBname% DIV256:\This points to the name
 1780 ]
 1790 A%=5:X%=block% MOD256:Y%=block% DIV256:CALLosfi
 1800 load%=!(block%+2):exec%=!(block%+6):REM Transfer attribs into variables
 1810 ENDPROC
 1820 :
 1830 DEFPROCmakeblock(state$)
 1840 REM A shorthand of # is used
 1850 IFstate$="MIDDLE" THEN?eoi%=ASC"#":eoi%=eoi%+1:eoi%=eoi%+FNloaddata(eoi%):ENDPROC:REM eoi% is the end of image ptr in main RAM,whereas next% is the eoi ptr in paged RAM
 1860 :
 1870 IFstate$="LAST" THENflag%=(128 ORprotect%) ELSEflag%=(0 ORprotect%)
 1880 :
 1890 REM Build a non shorthand block
 1900 !length%=FNloaddata(eoi%+LEN(dest$)+21)
 1910 P%=eoi%
 1920 [OPT2
 1930 EQUB ASC"*":EQUSdest$
 1940 EQUB0:EQUDload%:EQUDexec%
 1950 EQUWchunk%:EQUW(!length%-2)
 1960 EQUBflag%:EQUDnext%
 1970 ]
 1980 ?vL%=(eoi%+1)MOD256:?vH%=(eoi%+1)DIV256
 1990 eoi%=P%+!length%+2:!length%=21+LEN(dest$)-3:REM Don't include CRC or * in the CRC calculation!
 2000 cycle%=((USRcalccrc)AND&FFFF00)DIV&100
 2010 [OPT2:EQUWcycle%:]
 2020 
 2030 ENDPROC
 2040 :
 2050 DEFFNloaddata(dest%)
 2060 P%=block%
 2070 [OPT2
 2080 EQUB F:EQUDdest%:EQUD256
 2090 EQUD(256*chunk%):]
 2100 A%=3:X%=block% MOD256:Y%=block% DIV256:CALLosgbpb
 2110 ?vL%=dest% MOD256:?vH%=dest% DIV256:!length%=256-!(block%+5):REM Setup call for data CRC
 2120 cycle%=((USRcalccrc)AND&FFFF00)DIV&100
 2130 P%=dest%+!length%
 2140 [OPT2:EQUWcycle%:]:REM Place the data CRC and return with the amount of data read from disk +2 for the CRC
 2150 =(!length%)+2