68HC12 REGISTER SET
The following is a list of the 68HC12 registers used by AS6812:
a,b - 8-bit accumulators
d - 16-bit accumulator <a:b>
x,y - index registers
sp,s - stack pointer
pc - program counter
ccr,cc - condition code register
68HC12 INSTRUCTION SET
The following tables list all 68HC12 mnemonics recognized by
the AS6812 assembler. The designation [] refers to a required
addressing mode argument. The following list specifies the
format for each addressing mode supported by AS6812:
#data immediate data
byte or word data
ext extended addressing
pg memory page number
*dir direct page addressing
(see .setdp directive)
0 <= dir <= 255
label branch label
r,r1,r2 registers
ccr,a,b,d,x,y,sp,pc
-x x- register indexed, pre or
,-x ,x- post autodecrement by 1
n,-x n,x- register indexed, pre or
post autodecrement by 1 - 8
+x x+ register indexed, pre or
,+x ,x+ post autoincrement by 1
n,+x n,x+ register indexed, pre or
post autoincrement by 1 - 8
offset,x register indexed addressing
-16 <= offset <= 15 --- 5-bit
-256 <= offset <= -17 --- 9-bit
16 <= offset <= 255 --- 9-bit
-32768 <= offset <= -257 --- 16-bit
256 <= offset <= 32767 --- 16-bit
(external definition of offset
uses 16-bit mode)
[offset,x] register indexed indirect addressing
-32768 <= offset <= 32767 --- 16-bit
[,x] register indexed indirect addressing
zero offset
a,x accumulator offset indexed addressing
[d,x] d accumulator offset indexed
indirect addressing
The terms data, dir, label, offset, and ext may all be expres-
sions.
Note that not all addressing modes are valid with every in-
struction, refer to the 68HC12 technical data for valid modes.
Inherent Instructions
aba bgnd cba
daa dex dey
ediv edivs emul
emuls fdiv idiv
idivs inx iny
mem mul nop
psha pshb pshc
pshd pshx pshy
pula pulb pulc
puld pulx puly
rev revw rtc
rti rts sba
stop swi tab
tba wai wav
wavr
Short Branch Instructions
bcc label bcs label
beq label bge label
bgt label bhi label
bhis label bhs label
ble label blo label
blos label bls label
blt label bmi label
bne label bpl label
bra label brn label
bvc label bvs label
bsr label
Long Branch Instructions
lbcc label lbcs label
lbeq label lbge label
lbgt label lbhi label
lbhis label lbhs label
lble label lblo label
lblos label lbls label
lblt label lbmi label
lbne label lbpl label
lbra label lbrn label
lbvc label lbvs label
Branch on Decrement, Test, or Increment
dbeq r,label dbne r,label
ibeq r,label ibne r,label
tbeq r,label tbne r,label
Bit Clear and Set Instructions
bclr [],#data
bset [],#data
Branch on Bit Clear or Set
brclr [],#data,label
brset [],#data,label
Single Operand Instructions
asla aslb
asl []
asra asrb
asr []
clra clrb
clr []
coma comb
com []
deca decb
dec []
inca incb
inc []
lsla lslb
lsl []
lsra lsrb
lsr []
nega negb
neg []
rola rolb
rol []
rora rorb
ror []
tsta tstb
tst []
Double Operand Instructions
adca [] adcb []
adda [] addb []
anda [] andb []
bita [] bitb []
cmpa [] cmpb []
eora [] eorb []
ldaa [] <=> lda []
ldab [] <=> ldb []
oraa [] <=> ora []
orab [] <=> orb []
sbca [] sbcb []
staa [] <=> sta []
stab [] <=> stb []
suba [] subb []
Move Instructions
movb [],[] movw [],[]
D-register Instructions
addd [] subd []
cpd [] <=> cmpd []
ldd [] std []
Index/Stack Register Instructions
cps [] <=> cmps []
cpx [] <=> cmpx []
cpy [] <=> cmpy []
lds []
ldx [] ldy []
leas []
leax [] leay []
sts []
stx [] sty []
Jump and Jump/Call to Subroutine Instructions
call [],pg
jmp [] jsr []
Other Special Instructions
emacs []
emaxd [] emaxm []
emind [] eminm []
etbl []
maxa [] maxm []
mina [] minm []
tbl [] trap #data
H.2.14 Register - Register Instructions
exg r1,r2 sex r1,r2
tfr r1,r2
Condition Code Register Instructions
andcc #data orcc #data
M68HC11 Compatibility Mode Instructions
abx aby clc
cli clv des
ins sec sei
sev tap tpa
tsx tsy txs
tys xgdx xgdy