6F3B0250
Basic Hardware and Function
185
7. Instructions
FUN 071
SHL
n bit shift left
Expression
Input
-
[
A
SHL
n
®
B
]
-
Output
Function
When the input is ON, the data of register
A is shifted n bits to the left (MSB direction) including the
carry flag (CF = S050), and stored in
B. 0 is stored in lower n bits. After the operation, if the left most bit
(MSB) is ON, the output is turned ON.
Execution condition
Input
Operation
Output
CF
OFF
No execution
OFF
-
ON
Execution
When MSB = 1
ON
Set or reset
When MSB = 0
OFF
Set or reset
Operand
Name
Device
Register
Constant Index
X
Y
R
S
T.
C. XW YW RW SW
T
C
D
I
J
K
A
Source
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
n
Shift bits
1 - 16
B
Destination
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Ö
Example
When X008 is changed from OFF to ON, the data of RW18 is shifted 3 bits to the left and the
result is stored in RW20.
The figure below shows an operation example.
(MSB)
(LSB)
F
E
D
C
B
A
9
8
7
6
5
4
3
2
1
0
1 0 1 0 0 1 1 1 0 0 1 1 1 0 1 0
CF
1
0 0 1 1 1 0 0 1 1 1 0 1 0 0 0 0
R002 is turned OFF
0
RW18
RW20 (Result)
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