7. Device control
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Festo P.BE-CMMP-CO-SW-EN 0708NH
7.
Device control
7.1
Condition diagram (state machine)
7.1.1
Overview
The following chapter describes how the motor controller can be regulated under
CANopen, that is, how the final stage is switched on or an error is acknowledged, for
example.
Under CANopen, the entire regulation of the motor controller is achieved via two objects:
The host can regulate the motor controller via the
controlword
, while the status of the
motor controller can be read back in the object
statusword
. The following terms are used
to explain controller regulation:
Condition:
(state)
The motor controller is in different states, depending on whether
the final stage is switched on or an error has occurred, for
example. The conditions defined under CANopen are presented in
the course of the chapter.
Example:
SWITCH_ON_DISABLED
Condition transition
(state transition)
Just as with the conditions, CANopen also defines how to go from
one condition to another (e.g. to acknowledge an error). Condition
transitions are triggered by the host by setting bits in the
controlword
or internally through the motor controller, when it
recognises an error, for example.
Command
To trigger condition transitions, certain combinations of bits must
be set in the
controlword
. Such a combination is designated a
command.
Example:
Enable operation
Condition diagram
(state machine)
The conditions and condition transitions together form the
condition diagram, that is, the overview of all conditions and the
transitions possible from there.
Summary of Contents for CMMP Series
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