Programming manual M238 | 3 MB - BERGER - POSITEC

Controller States and Behaviors
Task and I/O Behavior When Update IO While In Stop Is Not Selected
When the Update IO while in stop setting is not selected, the controller sets the
I/O to either the Keep current values or Set all outputs to default condition (as
adjusted for output forcing if used). After this, the following becomes true:
The Read Inputs operation ceases. The %I input memory variablea are frozen
at their last values.
The Task Processing operation is not executed.
The Write Outputs operation ceases. The %Q output memory variables can be
updated via the Serial, and USB connections. However, the physical outputs
are unaffected and retain the state specified by the configuration options.
NOTE: if Q0, Q1, Q2 or Q3 outputs are configured for PTO, PWM, FG, or HSC
operation, they fallback to a value of 0 irrespective of the configured fallback setting.
For PTO operation, outputs Q0, Q1, Q2, and Q3 execute a fast stop deceleration.
Outputs configured for PWM, FG, and HSC go immediately to 0.
WARNING
UNINTENDED EQUIPMENT OPERATION
Design and program your system so that controlled equipment assumes a
safe state when the controller enters fallback mode if you use outputs Q0,
Q1, Q2, or Q3 for PTO, PWM, FG, or HSC operation.
Failure to follow these instructions can result in death, serious injury,
or equipment damage.
CAN Behavior When Update IO While In Stop Is Not Selected
The following is true for the CAN buses when the Update IO while in stop setting
is not selected:
The CAN Master ceases communications. Devices on the CAN bus assume
their configured fallback states.
TPDO and RPDO exchanges cease.
Optional SDO, if configured, exchanges cease.
The Heartbeat and Node Guarding functions, if configured, stop.
The current or default values, as appropriate, are written to the TPDOs and
sent once before stopping the CAN Master.
52 EIO0000000384 04/2012