Using Mcfb; Relevant Variable; Control Details - Mitsubishi Electric MELSEC iQ-R Series User Manual

18.2

Using MCFB

This section describes how to use the MCFB in PLC programs of the CPU module.

Relevant variable

Variable/Structure name
System.Md.
BuffermemoryFreeMcfbArea

Control details

The specifications of variables that are used for the MCFB of the CPU module side are shown below.
• Specifying AXIS_REF and AXES_GROUP_REF
When using the MCFB of the CPU module side, use the followings for the axis information (AXIS_REF) and the axes group
information (AXES_GROUP_REF) that are specified for the I/O variables of the MCFB.
AXIS_REF and AXES_GROUP_REF to be specified
AXIS_REF and AXES_GROUP_REF that are defined as labels in the CPU
module are used.
• Specifying the I/O No.
When using the MCFB of the CPU module side, the start I/O No. of the target Motion module has to be specified for the I/O
variables (AxisName.AxisRef.IO_No, etc.) used in the MCFB.
Each MCFB definitely defines one input variable that requires the IO_No setting. Refer to the following for the input variables
that require the IO_No setting.
24 List of FBs
For the MCFB that can input multiple variables whose member includes the IO_No, the setting of the IO_Nos excluding the
corresponding variables is not required. (The values are ignored.)
For the start I/O No. of the target module, refer to UNIT_LABEL.uIO of the module label or directly input the constant.
Be sure to establish the IO_No of each MCFB before the FB is called for the first time.
Generating MCFB instance
Control corresponding to the MCFB can be carried out in the Motion module side by instantiating the MCFB as a global label
or a local label on the CPU module and calling the MCFB on the PLC program.
CPU module
Label setting
Label name
Move1
Move2
PLC program
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18 HOW TO CONTROL FROM CPU MODULE
492
18.2 Using MCFB
Name
Buffer memory MCFB communication
area free size
Data type
MC_MoveAbsolute
MC_MoveAbsolute
Move1
Move2
Details
Indicates the number of unused points of the area for MCFB.
Setting
Set the members (the axis/axes group No. and the module I/O No. to be
controlled) of AXIS_REF and AXES_GROUP_REF by using the PLC
program.
Motion module
Buffer memory Motion control
(Area for MCFB) (PLCopen motion control
basic add-on)
Move1
Move2
Move1
Move2