Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 18

EN and ENO
EN (enable input) and ENO (enable output) can be appended to a function to control execution processing.
• Set a boolean variable used as an execution condition of a function to EN.
• A function with EN is executed only when the execution condition of EN is TRUE.
• Set a boolean variable used to output a function execution result to ENO.
For the boolean type, refer to the following.
Page 40 Data Types
The following table lists the ENO states and operation results according to the EN states.
EN
TRUE (executed)
FALSE (not executed)
• Setting an output label to ENO is not always required for the program written in ladder or FBD/LD.
• When EN/ENO is used in a standard function, the function with EN is represented by "function-name_E".
Creating programs
The program of a function can be created by using the engineering tool.
[Navigation window]  [FB/FUN]  Right-click  [Add New Data]
The created program is stored in the FB/FUN file.
[CPU Parameter]  [Program Setting]  [FB/FUN File Setting]
Up to 64 programs can be stored in one FB/FUN file.
For details on program creation, refer to the following.
Item
How to create function programs
Number of FB/FUN files that can be written to a CPU module
■ Applicable devices and labels
The following table lists the devices and labels that can be used in function programs.
: Applicable, : Applicable only in instructions (Cannot be used to indicate the program step.), : Not applicable
Type of device/label
Label (other than the pointer type)
Label (pointer type)
Device
Pointer
*1 The following data types cannot be used.
Timer, retentive timer, counter, long timer, long retentive timer, and long counter
Program a function name as a label in a function to set a return value of the function. Setting function names
as labels is not necessary. The data type set in "Result Type" in the properties of the function can be used.
3 PROGRAM ORGANIZATION UNITS
16
3.2 Functions (FUN)
ENO
TRUE
FALSE
Reference
 GX Works3 Operating Manual
 MELSEC iQ-R CPU Module User's Manual (Startup)
Global label
Local label
Pointer type global label
Pointer type local label
Global device
Local device
Global pointer
Local pointer
Operation result
Operation result output value
Undefined value
Availability

*1






