## AS6808 Assembler

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    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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