Apple II 6502 DASM v11

(adrLo adrHi opcode op1 op2, base64 encoded), enhanced 10-byte CPU trace records (adrLo adrHi opcode op1 op2 A X Y P SP, base64 encoded), or a regular memory dump such as F800: 4A 08 20 47 F8. In 10-byte trace mode, CPU registers are shown before the instruction because they represent pre-execution state. The viewer uses ../res/ASM_core.js for DASM and overrides symbols only on its own local instance. Every disassembly also logs a top-16 PC histogram and repeated closed instruction groups using console.table().

Boot log base64 / memory dump

Load .txt bootlog

Input mode ASM_core.js mem_sym friendly unofficial opcode names index column CPU state

Extra symbols

; accepted formats:
; COUT       EQU     $FDED   ;print ASCII character from accumulator
; IOADR      EQU     $C000   ;I/O address base
; $FDED=COUT;print ASCII character from accumulator
; COUT=$FDED;print ASCII character from accumulator
; 0xC000 IOADR;keyboard data/strobe

IOADR       EQU     $c000  
LOC0        EQU     $00
LOC1        EQU     $01
WNDLFT      EQU     $20
WNDWDTH     EQU     $21
WNDTOP      EQU     $22
WNDBTM      EQU     $23
CH          EQU     $24
CV          EQU     $25
GBASL       EQU     $26
GBASH       EQU     $27
BASL        EQU     $28
BASH        EQU     $29
BAS2L       EQU     $2A
BAS2H       EQU     $2B
COLOR       EQU     $30
MODE        EQU     $31
INVFLG      EQU     $32
PROMPT      EQU     $33
YSAV        EQU     $34
YSAV1       EQU     $35
CSWL        EQU     $36
KSWL        EQU     $38
PCL         EQU     $3A
PCH         EQU     $3B
A1L         EQU     $3C
A1H         EQU     $3D
A2L         EQU     $3E
A2H         EQU     $3F
A3L         EQU     $40
A3H         EQU     $41
A4L         EQU     $42
A4H         EQU     $43
A5L         EQU     $44
A5H         EQU     $45
ACC         EQU     $45     ;note overlap with A5H!
XREG        EQU     $46
YREG        EQU     $47
STATUS      EQU     $48
SPNT        EQU     $49
RNDL        EQU     $4E
RNDH        EQU     $4F
IN          EQU     $0200  
BRKV        EQU     $03f0   ;new vector for BRK
SOFTEV      EQU     $03f2   ;vector for warm start
PWREDUP     EQU     $03f4   ;this must = EOR #$A5 of SOFTEV+1
USRADR      EQU     $03f8  
NMI         EQU     $03fb  
IRQLOC      EQU     $03fe  
LINE1       EQU     $0400  
MSLOT       EQU     $07f8
KBD         EQU     $c000           ;R last key pressed + 128
KBDSTRB     EQU     $c010           ;RW keyboard strobe
TAPEOUT     EQU     $c020           ;RW toggle caseette tape output
SPKR        EQU     $c030           ;RW toggle speaker
TXTCLR      EQU     $c050           ;RW display graphics
TXTSET      EQU     $c051           ;RW display text
MIXSET      EQU     $c053           ;RW display split screen
TXTPAGE1    EQU     $c054           ;RW display page 1
LORES       EQU     $c056           ;RW display lo-res graphics
SETAN0      EQU     $c058           ;RW annunciator 0 off
SETAN1      EQU     $c05a           ;RW annunciator 1 off
CLRAN2      EQU     $c05d           ;RW annunciator 2 on
CLRAN3      EQU     $c05f           ;RW annunciator 3 on
TAPEIN      EQU     $c060
PADDL0      EQU     $c064           ;R analog input 0
PTRIG       EQU     $c070           ;RW analog input reset
CLRROM      EQU     $cfff           ;disable slot C8 ROM
BASIC       EQU     $e000
BASIC2      EQU     $e003
H2          EQU     $2C    
V2          EQU     $2D    
MASK        EQU     $2E

PLOT   EQU $F800
RTMASK EQU $F80C
PLOT1  EQU $F80E
HLINE  EQU $F819
HLINE1 EQU $F81C
VLINEZ EQU $F826
VLINE  EQU $F828
RTS1   EQU $F831
CLRSCR EQU $F832
CLRTOP EQU $F836
CLRSC2 EQU $F838
CLRSC3 EQU $F83C
GBASCA EQU $F847
GBCALC EQU $F856
NEXTCO EQU $F85F
SETCOL EQU $F864
SCRN   EQU $F871
SCRN2  EQU $F879
RTMSKZ EQU $F87F
LMNEM  EQU $F882
RMNEM  EQU $F882
FORMAT EQU $F882
LENGTH EQU $F882
INSDS1 EQU $F882
IEVEN  EQU $F89B
ERR    EQU $F8A5
GETFMT EQU $F8A9
MNNDX1 EQU $F8BE
MNNDX2 EQU $F8C2
MNNDX3 EQU $F8C9
INSTDS EQU $F8D0
PRNTOP EQU $F8D4
PRNTBL EQU $F8DB
NXTCOL EQU $F8F5
PRMN2  EQU $F8F9
PRADR1 EQU $F910
PRADR2 EQU $F914
PRADR3 EQU $F926
PRADR4 EQU $F92A
PRADR5 EQU $F930
RELADR EQU $F938
PRNTYX EQU $F940
PRNTAX EQU $F941
PRNTX  EQU $F944
PRBLNK EQU $F948
PRBL2  EQU $F94A
PCADJ  EQU $F953
PCADJ2 EQU $F954
PCADJ3 EQU $F956
PCADJ4 EQU $F95C
RTS2   EQU $F961
FMT1   EQU $F962
FMT2   EQU $F9A6
CHAR1  EQU $F9B4
CHAR2  EQU $F9BA
MNEML  EQU $F9C0
MNEMR  EQU $FA00
IRQ    EQU $FA40
BREAK  EQU $FA4C
OLDBRK EQU $FA59
RESET  EQU $FA62
FIXSEV EQU $FA9B
NOFIX  EQU $FAA3
PWRUP  EQU $FAA6
SETPG3 EQU $FAA9
LFAAB  EQU $FAAB
SLOOP  EQU $FABA    ; SLOT operations
NXTBYT EQU $FAC7
REGDSP EQU $FAD7
RGDSP1 EQU $FADA
RDSP1  EQU $FAE4
PWRCON EQU $FAFD
DISKID-1 EQU $FB01    ;is it a disk ??  (check for ROM sequence 3C->03->00->20)
DISKID EQU $FB02    ;is it a disk ??  (check for ROM sequence 3C->03->00->20)
TITLE  EQU $FB09
XLTBL  EQU $FB11
RTBL   EQU $FB19
PREAD  EQU $FB1E
PREAD2 EQU $FB25
RTS2D  EQU $FB2E
INIT   EQU $FB2F
SETTXT EQU $FB39
SETGR  EQU $FB40
SETWND EQU $FB4B
TABV   EQU $FB5B
APPLEI EQU $FB60
STITLE EQU $FB65
SETPWR EQU $FB6F
VIDWAI EQU $FB78
KBDWAI EQU $FB88
NOWAIT EQU $FB94
ESCOLD EQU $FB97
ESCNOW EQU $FB9B
ESCNEW EQU $FBA5
BASCAL EQU $FBC1
BASCLC EQU $FBD0
BELL1  EQU $FBD9
BELL2  EQU $FBE4
RTS2B  EQU $FBEF
STORAD EQU $FBF0
ADVANC EQU $FBF4
RTS3   EQU $FBFC
VIDOUT EQU $FBFD
BS     EQU $FC10
UP     EQU $FC1A
VTAB   EQU $FC22
VTABZ  EQU $FC24
RTS4   EQU $FC2B
ESC1   EQU $FC2C
CLREOP EQU $FC42
CLEOP1 EQU $FC46
HOME   EQU $FC58
CR     EQU $FC62
LF     EQU $FC66
SCROLL EQU $FC70
SCRL1  EQU $FC76
SCRL2  EQU $FC8C
SCRL3  EQU $FC95
CLREOL EQU $FC9C
CLEOLZ EQU $FC9E
CLREO2 EQU $FCA0
WAIT   EQU $FCA8
WAIT2  EQU $FCA9
WAIT3  EQU $FCAA
NXTA4  EQU $FCB4
NXTA1  EQU $FCBA
RTS4B  EQU $FCC8
HEADR  EQU $FCC9
WRBIT  EQU $FCD6
ZERDLY EQU $FCDB
ONEDLY EQU $FCE2
WRTAPE EQU $FCE5
RDBYTE EQU $FCEC
RDBYT2 EQU $FCEE
LASTIN EQU $FCFA
RD2BIT EQU $FCFA
RDBIT  EQU $FCFD
RDKEY  EQU $FD0C
KEYIN  EQU $FD1B
KEYIN2 EQU $FD21
ESC    EQU $FD2F
RDCHAR EQU $FD35
NOTCR  EQU $FD3D
NOTCR1 EQU $FD5F
CANCEL EQU $FD62
GETLNZ EQU $FD67
GETLN  EQU $FD6A
GETLN1 EQU $FD6F
BCKSPC EQU $FD71
NXTCHA EQU $FD75
CAPTST EQU $FD7E
ADDINP EQU $FD84
CROUT1 EQU $FD8B
CROUT  EQU $FD8E
PRA1   EQU $FD92
PRYX2  EQU $FD96
XAMB   EQU $FDA3
MOD8CH EQU $FDAD
XAM    EQU $FDB3
DATAOU EQU $FDB6
RTS4C  EQU $FDC5
XAMPM  EQU $FDC6
ADD    EQU $FDD1
PRBYTE EQU $FDDA
PRHEX  EQU $FDE3
PRHEXZ EQU $FDE5
COUT   EQU $FDED
COUT1  EQU $FDF0
COUTZ  EQU $FDF6
BL1    EQU $FE00
BLANK  EQU $FE04
RTS5   EQU $FE17
SETMOD EQU $FE18
SETMDZ EQU $FE1D
LT     EQU $FE20
LT2    EQU $FE22
MOVE   EQU $FE2C
VFY    EQU $FE36
VFYOK  EQU $FE58
LIST   EQU $FE5E
LIST2  EQU $FE63
A1PC   EQU $FE75
A1PCLP EQU $FE78
A1PCRT EQU $FE7F
SETINV EQU $FE80
SETNOR EQU $FE84
SETIFL EQU $FE86
SETKBD EQU $FE89
INPORT EQU $FE8B
INPRT  EQU $FE8D
SETVID EQU $FE93
OUTPOR EQU $FE95
OUTPRT EQU $FE97
IOPRT  EQU $FE9B
IOPRT1 EQU $FEA7
IOPRT2 EQU $FEA9
XBASIC EQU $FEB0
BASCON EQU $FEB3
GO     EQU $FEB6
REGZ   EQU $FEBF
TRACE  EQU $FEC2
STEPZ  EQU $FEC4
REMOVE EQU $FEC5
USR    EQU $FECA
WRITE  EQU $FECD
WR1    EQU $FED4
WRBYTE EQU $FEED
WRBYT2 EQU $FEEF
CHKSUM EQU $FEF6
CRMON  EQU $FEF6
READ   EQU $FEFD
RD2    EQU $FF0A
RD3    EQU $FF16
PRERR  EQU $FF2D
BELL   EQU $FF3A
RESTOR EQU $FF3F
RESTR1 EQU $FF44
SAVE   EQU $FF4A
SAV1   EQU $FF4C
OLDRST EQU $FF59
MON    EQU $FF65
MONZ   EQU $FF69
NXTITM EQU $FF73
CHRSRC EQU $FF7A
DIG    EQU $FF8A
NXTBIT EQU $FF90
NXTBAS EQU $FF98
NXTBS2 EQU $FFA2
GETNUM EQU $FFA7
NXTCHR EQU $FFAD
TOSUB  EQU $FFBE
ZMODE  EQU $FFC7
CHRTBL EQU $FFCC
SUBTBL EQU $FFE3

Disassembly