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AS6808 Assembler

68HC08 REGISTER SET 

The  following  is  a  list  of  the  68HC08  registers  used by
AS6808:  

        a       -       8-bit accumulator
        x       -       index register  <H:X>
        s       -       stack pointer


68HC08 INSTRUCTION SET 


   The  following tables list all 68HC08 mnemonics recognized by
the AS6808 assembler.  The designation [] refers to a required
addressing  mode  argument.   The  following  list specifies the
format for each addressing mode supported by AS6808:  

        #data           immediate data
                        byte or word data

        *dir            direct page addressing
                        (see .setdp directive)
                        0 <= dir <= 255 

        ,x              register indexed addressing
                        zero offset

        offset,x        register indexed addressing
                          0 <= offset <= 255   --- byte mode
                        256 <= offset <= 65535 --- word mode
                        (an externally defined offset uses the
                         word mode)

        ,x+             register indexed addressing
                        zero offset with post increment

        offset,x+       register indexed addressing
                        unsigned byte offset with post increment

        offset,s        stack pointer indexed addressing
                          0 <= offset <= 255   --- byte mode
                        256 <= offset <= 65535 --- word mode
                        (an externally defined offset uses the
                         word mode)

        ext             extended addressing

        label           branch label

The terms data, dir, offset, and ext may all be expressions.  

   Note  that  not all addressing modes are valid with every in-
struction, refer to the 68HC08 technical data for valid modes.  


Control Instructions 

        clc             cli             daa             div
        mul             nop             nsa             psha
        pshh            pshx            pula            pulh
        pulx            rsp             rti             rts
        sec             sei             stop            swi
        tap             tax             tpa             tsx
        txa             txs             wait


Bit Manipulation Instructions 

        brset   #data,*dir,label
        brclr   #data,*dir,label

        bset    #data,*dir
        bclr    #data,*dir


Branch Instructions 

        bra     label           brn     label
        bhi     label           bls     label
        bcc     label           bcs     label
        bne     label           beq     label
        bhcc    label           bhcs    label
        bpl     label           bmi     label
        bmc     label           bms     label
        bil     label           bih     label
        bsr     label           bge     label
        blt     label           bgt     label
        ble     label


Complex Branch Instructions 

        cbeqa   [],label
        cbeqx   [],label
        cbeq    [],label
        dbnza   label
        dbnzx   label
        dbnz    [],label


Read-Modify-Write Instructions 

        nega                    negx
        neg     []

        coma                    comx
        com     []

        lsra                    lsrx
        lsr     []

        rora                    rorx
        ror     []

        asra                    asrx
        asr     []

        asla                    aslx
        asl     []

        lsla                    lslx
        lsl     []

        rola                    rolx
        rol     []

        deca                    decx
        dec     []

        inca                    incx
        inc     []

        tsta                    tstx
        tst     []

        clra                    clrx
        clr     []              clrh

        aix     #data

        ais     #data


E.2.6  Register\Memory Instructions 

        sub     []              cmp     []
        sbc     []              cpx     []
        and     []              bit     []
        lda     []              sta     []
        eor     []              adc     []
        ora     []              add     []
        ldx     []              stx     []


Double Operand Move Instruction 

        mov     [],[]


16-Bit <H:X> Index Register Instructions 

        cphx    []
        ldhx    []
        sthx    []


Jump and Jump to Subroutine Instructions 

        jmp     []              jsr     []

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