RE: problem using motor record and SNL

[Mark Rivers <rivers@cars.uchicago.edu>]

The problem must be that your SNL code is effectively doing a ca_put_callback when it writes to the VAL field.  That will wait for the motor to complete the move.  Are you using the "SYNC" option on pvPut()?  If so you should remove it.

Mark


> -----Original Message-----
> From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf
> Of Hovanes Egiyan
> Sent: Friday, March 09, 2018 10:36 AM
> To: tech-talk@aps.anl.gov
> Cc: Vanik Kakoyan <kakoyan@jlab.org>
> Subject: problem using motor record and SNL
> 
> Hi,
> 
> we are trying to move a motor and then stop it using EPICS sequencer
> code and motor record.
> The state code dials the desired location into the VAL field via pvPut()
> and makes
> the motor move. If the user requests the motion to be aborted during the
> motion, the
> state code attempts to stop the motor either using STOP field or SPMG
> fields. And for some reason this does not work. Actual change of the
> SPMG field to
> "Stop" only happens when the motor motion is complete, and setting
> STOP field to 1 from the state code does not have any effect.
> 
> But if either moving the motor is done using caput to the VAL field or
> the stopping the motor is done via caput to the STOP or SPMG fields, it
> works. What is
> the reason for such a behavior? Is this expected? Any advice would be
> appreciated.
> 
> We are using motorR6-8 and seq-2.1.12 for this with R3-14-12-3 on RHEL6.
> 
> Thanks,
>      Hovanes Egiyan.