Step Function - Mitsubishi Electric MELSEC iQ-R-RD75P4 User Manual

Step function

Step function is used to check each operation of the positioning control.
This function is used in debugging work for the major positioning controls.
The positioning operation in which the step function is used is called a step operation.
In step operations, the timing for stopping the control can be set. (The setting is called the step mode.) The control stopped by
a step operation can be continued by using Step start request.
Relation between the step function and various controls
The following table shows the relation between Step function and various controls.
: Set as required, : Setting not possible
Control type
OPR control Machine OPR control
Fast OPR control
Major positioning control Position control
1-/2-/3-/4-axis speed control
Speed-position switching control, Position-speed
switching control
Other controls
Manual control JOG operation, Inching operation
Manual pulse generator operation
Step mode
In step operations, the timing for stopping the control can be set. (The setting is called the step mode.) (Step mode is set in
the control data [Cd.34] Step mode.)
Step mode is classified into the following two types.
■Deceleration unit step
The operation stops at the positioning data requiring automatic deceleration. (A normal operation will be performed until the
positioning data No. requiring automatic deceleration takes its turn. Once the turn comes, the positioning data will be
executed, and the operation will automatically decelerate and stop.)
■Data No. unit step
The operation automatically decelerates and stops for each positioning data. (Even in the continuous path control, the
automatic deceleration and the stop will be forcibly performed.)
Step function



1-axis linear control
2-/3-/4-axis linear 
interpolation control

1-axis fixed-feed control

2-/3-/4-axis fixed-feed
control

2-axis circular
interpolation control

3-axis helical
interpolation control



Current value change

JUMP instruction, NOP
instruction
LOOP to LEND


Step applicability
Step operation not possible
Step operation possible
Step operation not possible
Step operation possible
Step operation not possible
Step operation not possible
7 CONTROL SUB FUNCTIONS
7.8 Function Related to Stop
7
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