Function Blocks (Fb) - Mitsubishi Electric MELSEC iQ-F Series Programming Manual

• EN/ENO
The following table lists the number of steps required for EN/ENO.
Item
EN
ENO
3.3

Function Blocks (FB)

A function block is a POU called and executed by program blocks and other function blocks.
Function
block
Unlike a function, a function block does not have a return value.
A function block can hold values in variables and thus can hold input states and processing results.
A function block uses the value it holds for the next processing and therefore it does not always output the same result even
with the same input value.
Ladder language
A function block needs to be instantiated to be used in programs.
Page 21 Instances
• For details on standard function blocks, refer to the following.
 MELSEC iQ-F FX5 Programming Manual (Instructions, Standard Functions/Function Blocks)
• For details on module function blocks, refer to the following.
 Function Block Reference for the module used
3 PROGRAM ORGANIZATION UNITS
18
3.3 Function Blocks (FB)
Number of steps
4 to 7
(The number of steps differs depending on the details of the program such as the type and number of the device specified as the
input source of EN.)
6 to 10
(The number of steps differs depending on the details of the program such as the type and number of the device specified as the
output destination of ENO.)
Function
block
FB
FBD/LD language
(1)
(2)
(3)
(4)
Program
block
FB
Program
block
FB
(1) Instance name
(1)
(2) Function block name
(2)
(3) Output variable
(4) Input variable
(3)
(4)