SM8951B Datasheet, PDF (13/18 Pages) SyncMOS Technologies,Inc – 8-Bits Micro-controller

SyncMOS Technologies International, Inc.
SM8951B
8-Bits Micro-controller
With4KBFlashROM&128bytesRAM embedded
Instruction Set
The SM8951B uses the powerful instruction set of 80C51. It consists of 49 single-byte, 42 two-byte, and 15 three-
byte instructions. Among them 63 instruction are executed in 1 machine-cycle, 46 instructions in 2 machine-cycles,
and the multiply, 2 instructions in 4 machine-cycles.
A summary of the instruction set is given in Table 3.
Addressing Mode
Notes on instruction set and address modes:
Rn
direct
@Ri
#data
#data16
addr11
rel
bit
Register R7-R0 of the currently selected register bank.
8-bits internal data location’s address. This could be internal DATA RAM location (0-127) or a
SFR [i.e., I/O port, control register, status register, etc. (128-255)]
8-bits RAM location addressed indirectly through register R1 or R0 of the actual register bank
8-bits constant included in the instruction
16-bits constant included in the instruction
11-bits destination address. Used by ACALL and AJMP. The branch can be anywhere within the
same 2 Kbytes page of program memory as the first byte of the following instruction.
Signed (2’s complement) 8-bits offset byte. Used by SJMP and all conditional jumps. Range is
-128 to +127 bytes relative to first byte of the following instruction.
Direct addressed bit in internal data RAM or SFR
Mnemonic
Arithmetic Instructions
ADD
A,Rn
ADD
A,direct
ADD
A,@Ri
ADD
A,#data
ADDC
A,Rn
ADDC
A,direct
ADDC
ADDC
SUBB
SUBB
SUBB
SUBB
INC
INC
INC
INC
DEC
DEC
DEC
DEC
INC
MUL
DIV
A,@Ri
A,#data
A,Rn
A,direct
A,@Ri
A,#data
A
Rn
direct
@Ri
A
Rn
direct
@Ri
DPTR
AB
AB
DA
A
Logical Instructions
ANL
A,Rn
ANL
A,direct
ANL
A,@Ri
ANL
A,#data
ANL
direct,A
ANL
direct,#data
ORL
A,Rn
ORL
A,direct
ORL
A,@Ri
Table 3: A Summary of the instruction set
OPERATION
A = A + Rn
A = A + direct
A = A + <@Ri>
A = A + #data
A = A + Rn + C
A = A + direct + C
A = A + @Ri + C
A = A + #data + C
A = A － Rn － C
A = A － direct － C
A = A － <@Ri> － C
A = A－#data － C
A=A+1
Rn = Rn + 1
direct = direct + 1
<@Ri> = <@Ri> + 1
A=A － 1
Rn = Rn － 1
direct = direct － 1
<@Ri> = <@Ri> － 1
DPTR = DPTR － 1
B:A = A × B
A = INT (A/B)
B = MOD (A/B)
Decimal adjust ACC
A .AND. Rn
A .AND. direct
A .AND. <@Ri>
A .AND. #data
direct .AND. A
direct .AND. #data
A .OR. Rn
A .OR. direct
A .OR. <@Ri>
BYTE
1
2
1
2
1
2
1
2
1
2
1
2
1
1
2
1
1
1
2
1
1
1
1
1
1
2
1
2
2
3
1
2
1
CYCLE
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
4
4
1
1
1
1
1
1
2
1
1
1
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M022Ver:BSM8951B
13
06/2009