Allen-Bradley controllogix 1756-L63, User Manual

Page: 399 / 435

Publication 1756-UM001E-EN-P - August 2002
Program Motion Control 24-19
Develop Logic for Motion
Control
To write a motion application program, you can insert motion
instructions directly into your ladder logic program.
The motion instructions operate on one or more axes. You must
identify and configure axes before you can use them. For more
information about configuring axes, see the
ControlLogix Motion
Module Setup and Configuration Manual , publication 1756-UM006.
For more information on individual motion instructions, see the
Logix5000 Controllers Motion Instruction Set Reference Manual ,
publication 1756-RM007.
Each motion instruction has an operand named Motion control. This
field uses a MOTION_INSTRUCTION tag to store status information
during the execution of motion instructions. This status information
can include instruction status, errors, etc.
For more information about the MOTION_INSTRUCTION tag, refer to
the appropriate motion instruction in the
Logix5000 Controllers
Motion Instruction Set Reference Manual , publication 1756-RM007.
You can read motion status and configuration parameters in your logic
using two methods.
ATTENTION
!
Tags used for the motion control operand of motion
instruction should only be used once. Re-use of the
same motion control operand in other instructions
can cause unintended operation of the control
variables.
Method: Example:
Directly accessing the MOTION_GROUP
and AXIS structures
•
Axis faults
•
Motion status
Using the GSV instruction Actual position
Enable the Auto Tag Update attribute for a
motion group CommandAcceleration
The
Motion control
operand
Allen-Bradley HMIs