Experimental Physics and
Industrial Control System

Torsten Bögershausen <[email protected]> · Mon, 16 Nov 2015 09:54:27 +0100

On 11/11/15 16:18, Pearson, Matthew R. wrote:


Hi,

There seems to be a problem with issuing a motor record STOP while we are waiting for a DLY settling time to expire. I can lock up the motor record if I issue a STOP after MOVN has gone to zero and before DMOV goes to 1. This only seems to be a problem if there are no further updates from the driver (so we have already stopped moving). It’s easy to reproduce using a simulation driver.


Now I can reproduce it.
Are you using a model 3 driver ?


If yes, then one reason is, that the poll() updates are "filtered" here, and

the motorRecord is not processed,

when the encoder/motor is not moving at all in the DLY phase:

asynStatus asynMotorAxis::callParamCallbacks()
{
  if (statusChanged_) {
    statusChanged_ = 0;
    pC_->doCallbacksGenericPointer((void *)&status_, pC_->motorStatus_, axisNo_);
  }
  return pC_->callParamCallbacks(axisNo_);
}
----------------------
A "first aid help" quickfix can look like this:

Expose the statusChanged_ (move it out from private to protected in

asynMotorAxis.h)

diff --git a/motorApp/MotorSrc/asynMotorAxis.h b/motorApp/MotorSrc/asynMotorAxis.h
index 4b22e85..1342b20 100644
--- a/motorApp/MotorSrc/asynMotorAxis.h
+++ b/motorApp/MotorSrc/asynMotorAxis.h
@@ -63,10 +63,10 @@ class epicsShareFunc asynMotorAxis {

 double *profileReadbacks_; /**< Array of readback positions for

profile moves */

 double *profileFollowingErrors_; /**< Array of following errors for

profile moves */

   int referencingMode_;
+  int statusChanged_;

   private:
   MotorStatus status_;
-  int statusChanged_;
   int referencingModeMove_;

   friend class asynMotorController;


-----------------
The change the driver to set statusChanged_ = 1 in the poll() function:
+  statusChanged_ = 1;


----------------------
This will make the motorRecord to be processed and get out of the DLY phase.

A better handling may be to have a flag that does not filter the callbacks,
whenever the motor record is used with a model 3 driver.

asynStatus asynMotorAxis::callParamCallbacks()
{
  if (statusChanged_ || isMotorRecordnowFilterButAlwaysProcess_) {
    statusChanged_ = 0;
    pC_->doCallbacksGenericPointer((void *)&status_, pC_->motorStatus_, axisNo_);
  }
  return pC_->callParamCallbacks(axisNo_);
}

Any thoughts ?


Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System