MS51
Nov. 28, 2019
Page
489
of 491
Rev 1.00
MS51
32K
SE
RIES
TE
CHNICAL RE
F
EREN
CE MA
N
UAL
Instruction
OPCODE
Bytes
Clock
Cycles
MS51 V.S. Tradition
80C51 Speed Ratio
ORL
C, bit
72
2
3
8
ORL
C, /bit
A0
2
3
8
MOV
C, bit
A2
2
3
4
MOV
bit, C
92
2
4
6
ACALL
addr11
11, 31, 51, 71, 91, B1, D1, F1
[2]
2
4
6
LCALL
addr16
12
3
4
6
RET
22
1
5
4.8
RETI
32
1
5
4.8
AJMP
addr11
01, 21, 41, 61, 81, A1, C1, E1
[3]
2
3
8
LJMP
addr16
02
3
4
6
SJMP
rel
80
2
3
8
JMP
@A+DPTR
73
1
3
8
JZ
rel
60
2
3
8
JNZ
rel
70
2
3
8
JC
rel
40
2
3
8
JNC
rel
50
2
3
8
JB
bit, rel
20
3
5
4.8
JNB
bit, rel
30
3
5
4.8
JBC
bit, rel
10
3
5
4.8
CJNE
A, direct, rel
B5
3
5
4.8
CJNE
A, #data, rel
B4
3
4
6
CJNE
Rn, #data, rel
B8~BF
3
4
6
CJNE
@Ri, #data, rel
B6, B7
3
6
4
DJNZ
Rn, rel
D8~DF
2
4
6
DJNZ
direct, rel
D5
3
5
4.8
Note
:
[1] The MS51 does not have external memory bus. MOVX instructions are used to access internal XRAM.
[2] The most three significant bits in the 11-bit address [A10:A8] decide the ACALL hex code. The code will be
[A10,A9,A8,1,0,0,0,1].
[3]
The most three significant bits in the 11-bit address [A10:A8] decide the AJMP hex code. The code will be
[A10,A9,A8,0,0,0,0,1].
Table 11.2-1 Instruction Set