Delta Electronics DVP15MC11T, Руководство по эксплуатации

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Chapter 8 Logic Instructions
8_
8.14.7 LEN
FB/FC Explanation
Applicable
model
FC LEN calculates the number of characters in a string. DVP15MC11T

Parameters
Parameter
name
Meaning
Input/
Output
Description Valid range
In String Input String
Depends on the data type of the
variable that the input parameter is
connected to.
Out
Number of
characters
Output
Number of
characters
Depends on the data type of the
variable that the output parameter is
connected to.
B
ool
ean
Bit string Integer
Real
number
Time, date
St
rin
g
B
O
O
L
BYT
E
WO
RD
D
WO
R
D
L
W
O
R
D
U
SI
N
T
U
IN
T
U
DI
NT
U
L
INT
SI
N
T
IN
T
D
IN
T
L
IN
T
R
EAL
L
R
EAL
T
IM
E
D
AT
E
TOD D
T
ST
R
IN
G
In
●
Out
●
Note:
The symbol
●
indicates that the parameter is allowed to connect to the variable or constant of the data type.

Function Explanation
The LEN instruction finds the number of characters in a string and the result is output to Out . For
example, when the string is ABCDEFGH, the value of Out is 8.

Precautions for Correct Use
The input variables are not allowed to omit. An error will occur during the compiling of the software if the
input variables are omitted. But the output variable is allowed to omit.

Programming Example

The LEN_In string is ’AaBbCcDd’. As LEN_EN is TRUE, the value of Out1 is 8.

The variable table and program
Variable name Data type Current value
LEN_EN BOOL TRUE
LEN_In STRING AaBbCcDd
Out1 UINT 8
LEN
EN ENO
In Ou t
1
LEN
EN ENO
I n O ut
L EN_EN
LEN_In Out 1
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