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 []