100DIM workspace 10
  200PROCInitTables
  300 
  400 
  500Illegal$ = "?"
  600*LOAD :1.Etweak
  601*SPOOL :1.ETEXT
  700PROCDisassemble(&2E00,&1B0)
  710FOR PC=&2FBC TO &2FFF
  711   PRINT"                   EQUB &"+FNHex(PC?0,2)
  712NEXT
  800*SPOOL
  900END
 1000 
 1101DEFPROCDisassemble(Start,Length)
 1200PC = Start
 1300REPEAT
 1400   Lab$=FNlabel(PC)
 1500   IF ASC(Lab$)<>ASC("&") IF INSTR(Lab$,"+")<=0 THEN PRINT "                .";Lab$ 
 1600   PC = PC+FN_dis(PC)
 1700   IF Opcode=&60 OR Opcode=&4C THEN PRINT
 1800   IF PC=&2F01 THEN PC=PC+FNillegal(PC?0)
 1900UNTIL PC >= Start+Length
 2100ENDPROC
 2200 
 2300DEFFN_dis(P)
 2400   Opcode = ?P
 2500   Mode$ = FNmode(Opcode)
 2600   Name$ = FNname(Opcode)
 2700   IF Mode$ = Illegal$ THEN =FNillegal (Opcode)
 2800   ON INSTR(" ARI&#XYxyz()",Mode$) GOTO 3200,3600,5900,6300,                                 6700,7200,7600,8100,8600,9100,9600,10200,10600 ELSE
 2900 PRINT "Keith Error: Mode = "+Mode$
 3000 
 3100 
 3200REM " " - Implicit
 3300=FNOpcode (1,"")
 3400 
 3500 
 3600REM "A" - Accumulator
 3700=FNOpcode (1," A")
 3800 
 3900 
 4000   IF Addr<&300 THEN 5800 
 4100   IF Addr>&3FF THEN 5800
 4200   IF FNx(Addr,&31B,8) THEN="Vdu_queue"+FNr(Addr-&31B)
 4202   IF FNx(Addr,&31B,2) THEN="TRINLN"+FNr(Addr-&31B)
 4300   IF FNx(Addr,&31F,1) THEN="Plot_mode"
 4400   IF FNx(Addr,&320,2) THEN="NewPoint"+FNr(Addr-&320)
 4500   IF FNx(Addr,&323,1) THEN="Queue_end"
 4600   IF FNx(Addr,&326,2) THEN="Gr_CursorY_int"+FNr(Addr-&326)
 4700   IF FNx(Addr,&324,2) THEN="Gr_CursorX_int"+FNr(Addr-&324)
 4800   IF FNx(Addr,&226,2) THEN="ExtensionVec"+FNr(Addr-&226)
 4900   IF FNx(Addr,&355,1) THEN="Mode"
 5000   IF FNx(Addr,&356,1) THEN="MemMode"
 5100   IF FNx(Addr,&357,1) THEN="ForeTxtCol"
 5200   IF FNx(Addr,&358,1) THEN="BackTxtCol"
 5300   IF FNx(Addr,&359,1) THEN="ForeGfxCol"
 5400   IF FNx(Addr,&35A,1) THEN="BackGfxCol"
 5500   IF FNx(Addr,&35B,1) THEN="ForePlotCol"
 5600   IF FNx(Addr,&35C,1) THEN="BackPlotCol"
 5700   IF FNx(Addr,&35D,2) THEN="JMI_vec"+FNr(Addr-&35D)
 5800GOTO 14100
 5900REM "R" - Relative
 6000=FNOpcode (2," "+FNlabel(P+2+FNsex(P?1)))
 6100 
 6200 
 6300REM "I" - Indirect
 6400=FNOpcode (3," ("+FNlabel(FNpair)+")")
 6500 
 6600 
 6700REM "&" - Absolute
 6800Extra$ = ""
 6900=FNOpcode (3," "+FNlabel(FNpair)+Extra$)
 7000 
 7100 
 7200REM "#" - Immediate
 7300=FNOpcode (2," #"+STR$(P?1))
 7400 
 7500 
 7600REM "X" - Absolute, X
 7700Extra$ = ",X"
 7800GOTO 6900
 7900 
 8000 
 8100REM "Y" - Absolute, Y
 8200Extra$ = ",Y"
 8300GOTO 6900
 8400 
 8500 
 8600REM "x" - Xero page, X
 8700Extra$ = ",X"
 8800GOTO 9800
 8900 
 9000 
 9100REM "y" - Zero page, Y
 9200Extra$ = ",Y"
 9300GOTO 9800
 9400 
 9500 
 9600REM "z" - Zero page
 9700Extra$ = ""
 9800=FNOpcode (2," "+FNlabel(FNsingle)+Extra$)
 9900 
10000 
10100 
10200REM "(" - Pre indexed by X
10300=FNOpcode (2," ("+FNlabel(FNsingle)+",X)")
10400 
10500 
10600REM ")" - Post indexed by Y
10700=FNOpcode (2," ("+FNlabel(FNsingle)+"),Y")
10800 
10900DEFFNillegal(Opcode)
11000   PROCaddress(3)
11100   IF ASC(" ")<=(PC?1) AND (PC?1)<=ASC("~") THEN =FNascii
11200   PRINT "   EQUB ";
11300   IF ASC(" ")<=Opcode AND Opcode<=ASC("~") THEN PRINT "ASC(""";CHR$(Opcode);""")" ELSE PRINT "&";STR$~(Opcode)
11400PRINT
11500=1
11600 
11700DEFFNascii
11800   PRINT "   EQUS """;
11900   Count = 0
12000REM
12100   IF ASC(" ")<=(PC?Count) AND (PC?Count)<=ASC("~") THEN VDU PC?Count:Count=Count+1: GOTO 12000
12200   PRINT""": EQUB &"+FNHex(PC?Count,2)
12300PRINT
12400=Count+1
12500 
12600 
12700DEFFNsex(Byte)
12800IF Byte >= 128 THEN =(Byte OR &FFFFFF00) ELSE =Byte
12900 
13000 
13100DEFFNpair
13200   = (P?2)*256 + (P?1)
13300 
13400 
13500DEFFNsingle
13600   = (P?1)
13700 
13800 
13900DEFFNlabel(Addr)
14000GOTO4200
14100  IF FNx(Addr,&33D,1) THEN="S_direction"
14200  IF Addr=&26A THEN = "Pending"
14300  IF FNx(Addr,&332,1) THEN="H_direction"
14400  IF FNx(Addr,&32E,4) THEN="H_start"+FNr(Addr-&32E)
14500  IF FNx(Addr,&339,4) THEN="S_start"+FNr(Addr-&339)
14600  IF FNx(Addr,&328+13,2) THEN="SDELTA"+FNr(Addr-(&328+13))
14700  IF FNx(Addr,&328,&22) THEN="Vdu_workspace"+FNr(Addr-&328)
14800  IF Addr=&D411 THEN ="TRISA"
14900  IF Addr=&D459 THEN ="TRISB"
15000  IF Addr=&D628 THEN ="RestoreCursor"
15100  IF Addr=&D632 THEN ="SORTA"
15200  IF Addr=&D636 THEN ="SORTY"
15300  IF Addr=&E0A4 THEN ="WRCH"
15400  IF Addr=&D0DE THEN ="EMAEZ"
15500  IF Addr=&D774 THEN ="ULN"
15600  IF Addr=&D0B3 THEN ="SETZB"
15700  IF Addr=&D6A2 THEN ="HPLOT"
15800  IF Addr=&D47C THEN ="COPYF"
15900  IF Addr=&CDE2 THEN ="SWAPB"
16000  IF Addr=&CDE4 THEN ="SWAPC"
16100  IF Addr=&224 THEN ="NewPoint-&FC"
16200  IF Addr<&2E00 OR Addr>&2FFF THEN 17900
16300  IF Addr=&2E38 THEN = "OrdinaryVDU"
16400  IF Addr=&2E21 THEN = "Loop1"
16500  IF Addr=&2E64 THEN = "Get_GCOL"
16600  IF Addr=&2E40 THEN = "Get_PLOT"
16700  IF FNx(Addr,&2E00,4) THEN ="Buffer"+FNr(Addr-&2E00)
16800  IF Addr=&2E04 THEN = "VDU_entry"
16900  IF FNx(Addr,&2F00,2) THEN ="Temp"+FNr(Addr-&2F00) 
17000  IF Addr=&2E3B THEN = "ConstAA"
17100  IF Addr=&2E5C THEN = "SetVector"
17200  IF Addr=&2E75 THEN = "SetJMItab"
17300  IF Addr=&2EA4 THEN = "GCOL_64"
17400  IF Addr=&2E1C THEN = "TrapMode"
17500  IF Addr=&2E2C THEN = "test_VDU_command"
17600  IF Addr=&2E88 THEN = "GCOL_32"
17700  IF Addr=&2F6F THEN = "TrapPLOT"
17702   IF Addr=&2F12 THEN ="trsrts"
17704   IF Addr=&2F13 THEN ="trsf"
17706   IF Addr=&2F43 THEN ="trsfb"
17708   IF Addr=&2F5A THEN ="trsfa"
17710   IF Addr=&2F5D THEN ="hplot"
17720   IF Addr=&2EA8  THEN ="Loop2"
17730   IF Addr=&2EE7  THEN ="Loop3"
17740   IF Addr=&2E97  THEN ="Skip3"
17750   IF Addr=&2ED2  THEN ="Shift2"
17760   IF Addr=&2EF5  THEN ="Loop4"
17770   IF Addr=&2F06  THEN ="Skip1"
17780   IF Addr=&2F0F  THEN ="Skip2"
17782   IF Addr=&2EB3  THEN ="Proc1"
17784   IF Addr=&2EC9  THEN ="Proc2"
17786   IF Addr=&2EE1  THEN ="Proc3"
17788   IF Addr=&2EED  THEN ="Proc4"
17790   IF Addr=&2F02  THEN ="Proc5"
17800   IF FNx(Addr,&2FB0,&50) THEN ="Data"+FNr(Addr-&2FB0)
17900   ="&"+STR$~(Addr)
18000 
18100DEFFNOpcode (Size, Operand$)
18200   PROCaddress(Size)
18300   PRINT "   "; Name$; Operand$
18400   =Size
18500 
18600 
18700DEFFNx(Addr,Low,Size)
18800    =(Low <= Addr AND Addr < Low+Size)
18900 
19000 
19100 
19200DEFFNr(Offset)
19300IF Offset>0 THEN = "+"+STR$(Offset)
19400=""
19500 
19600 
19700 
19800DEFPROCaddress(Size)
19900   PRINT "\ ";FNHex(PC,4);
20000   FOR p = 1 TO 3
20100      IF p <= Size THEN PRINT " "FNHex(PC?(p-1),2); ELSE PRINT "   ";
20200   NEXT
20300   PRINT":";
20400ENDPROC
20500 
20600 
20700DEFFNHex(I,J)
20800   = RIGHT$("000"+STR$~(I),J)
20900 
21000 
21100 
21200 DEF PROCInitTables
21300 LOCAL a,b
21400 DIM Opcodes%(255)
21500 FOR a = 0 TO 15
21600  READ entry$
21700  FOR b = 0 TO 15
21800   Opcodes%(a*16 + b)=FNencode(MID$(entry$,b*4+1,4))
21900  NEXT
22000 NEXT
22100 
22200 ENDPROC
22300 
22400 DEF FNencode(string$) : REM Packs a 4 character string into 4 bytes !!!
22500 $workspace=string$
22600 =!workspace
22700 
22800 DEF FNname(op)
22900 LOCAL name$
23000 workspace?4=13
23100 !workspace=Opcodes%(op)
23200 name$=$workspace
23300 =MID$(name$,1,3)
23400 
23500 DEF FNmode(op)
23600 LOCAL name$
23700 !workspace=Opcodes%(op)
23800 workspace?4=13
23900 name$=$workspace
24000 =MID$(name$,4,1)
24100 
24200 REM Data table of all opcodes
24300 REM Each entry is 3 chars of opcode + one char of addressing mode
24400 REM The modes are :-
24500 REM   None ( Space )
24600 REM A Acc
24700 REM R Relative
24800 REM I Indirect
24900 REM & Absolute
25000 REM # Immediate
25100 REM z Zpage
25200 REM x Zpage,X
25300 REM y Zpage,Y
25400 REM X Abs,X
25500 REM Y Abs,Y
25600 REM ( Ind,X
25700 REM ) Ind,Y
25800 REM ? Illegal
25900  
26000 REM "&x0 &x1 &x2 &x3 &x4 &x5 &x6 &x7 &x8 &x9 &xA &xB &xC &xD &xE &xF
26100 DATA"Brk Ora(????????????OrazAslz????Php Ora#AslA????????Ora&Asl&????"
26200 DATA"BplROra)????????????OraxAslx????Clc OraY????????????OraXAslX????"
26300 DATA"Jsr&And(????????BitzAndzRolz????Plp And#RolA????Bit&And&Rol&????"
26400 DATA"BmiRAnd)????????????AndxRolx????Sec AndY????????????AndXRolX????"
26500 DATA"Rti Eor(????????????EorzLsrz????Pha Eor#LsrA????Jmp&Eor&Lsr&????"
26600 DATA"BvcREor)????????????EorxLsrx????Cli EorY????????????EorXLsrX????"
26700 DATA"Rts Adc(????????????AdczRorz????Pla Adc#RorA????JmpIAdc&Ror&????"
26800 DATA"BvsRAdc)????????????AdcxRorx????Sei AdcY????????????AdcX????????"
26900 DATA"????Sta(????????StyzStazStxz????Dey ????Txa ????Sty&Sta&Stx&????"
27000 DATA"BccRSta)????????StyxStaxStxy????Tya StaYTxs ????????StaX????????"
27100 DATA"Ldy#Lda(Ldx#????LdyzLdazLdxz????Tay Lda#Tax ????Ldy&Lda&Ldx&????"
27200 DATA"BcsRLda)????????LdyxLdaxLdxy????Clv LdaYTsx ????LdyXLdaXLdxY????"
27300 DATA"Cpy#Cmp(????????CpyzCmpzDecz????Iny Cmp#Dex ????Cpy&Cmp&Dec&????"
27400 DATA"BneRCmp)????????????CmpxDecx????Cld CmpY????????????CmpXDecX????"
27500 DATA"Cpx#Sbc(????????CpxzSbczIncz????Inx Sbc#Nop ????Cpx&Sbc&Inc&????"
27600 DATA"BeqRSbc)????????????SbcxIncx????Sed SbcY????????????SbcXIncX????"