Experimental Physics and
Industrial Control System

Mark Rivers <[email protected]> · Wed, 29 Jun 2016 19:39:41 +0000

I think the motor record does always sets the VAL field to match the RBV field when motion completes.  This is true regardless of whether you are using deferred moves or not.

What happens if you do the same camonitor on a normal move of this axis, not a deferred move? 

Why your controller is saying that the position is 3.993 and that the move is complete, when it was told to go to 4.000?  Does this motor have an encoder?  Are you using the encoder for readback, i.e. what is the value of the UEIP field? 

Mark

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Ron Sluiter
Sent: Wednesday, June 29, 2016 2:23 PM
To: Jacob DeFilippis
Cc: [email protected]
Subject: Re: Motor Module, Deferred Movement, .VAL field set to .RBV after motion

Hello Jacob,

What version (VERS field) of the motor record are you using?

The folks at Diamond are the experts in the use of the motor record 
deferred move function. I defer to them on this topic.

Ron

On 6/29/2016 1:32 PM, Jacob DeFilippis wrote:
> Hello,
>     I am working on implementing a multiple axis synchronized motion 
> using the motor module's asynController base class (model 3). The move 
> function is set up such that  it stores the .VAL to variables inside 
> the physical controller when the deferredMove flag is 1, and when 
> there is a transition from 1-> 0 on the flag I issue the controller 
> command that moves the motors synchronously to the commanded target.
>
>     My problem is when the move completes the .VAL field is set to the 
> .RBV field.  This happens when the .DMOV is returned to 1. I tracked 
> down the cause, which is found in motorRecord.cc in function  
> postProcess(motorRecord * pmr) line 762 (In the github repo). It 
> executes "pmr->val = pmr->rbv" . I am unsure why this postprocess is 
> occurring.  Is there anything extra I should implement in my function 
> that issues synchronized motion?  or possibly something extra in the 
> polling function. Is this because the RTRY field is set to 0?
>
> An example of the bad behavior:
> SMOTOR:AXIS:1.VAL                 2016-06-29 11:05:24.259733 4
> SMOTOR:AXIS:1.DMOV            2016-06-29 11:05:24.474977 1
> SMOTOR:AXIS:1.RBV                2016-06-29 11:05:27.892752 3.0181
> SMOTOR:AXIS:1.DMOV            2016-06-29 11:05:27.892752 0
> SMOTOR:AXIS:1.RBV                2016-06-29 11:05:30.090092 3.4665
> SMOTOR:AXIS:1.RBV                2016-06-29 11:05:32.287451 3.9155
> SMOTOR:AXIS:1.RBV                2016-06-29 11:05:34.484984 3.9993
> SMOTOR:AXIS:1.VAL                 2016-06-29 11:05:34.484984 3.9993 
> <--My problem
> SMOTOR:AXIS:1.DMOV            2016-06-29 11:05:34.484984 1
>
> My motor record
> record(motor, "$(P):$(M):$(ADDR)") {
>   field(SCAN, "Passive")
>   field(DTYP, "asynMotor")
>   field(DISS, "NO_ALARM")
>   field(DIR, "$(DIR)")
>   field(VELO, "$(VELO)")
>   field(VBAS, "$(VBAS)")
>   field(VMAX, "$(VMAX)")
>   field(URIP, "No")
>   field(PREC, "4")
>   field(EGU, "mm")
>   field(MRES, "$(MRES)")
>   field(OUT, "@asyn($(PORT),$(ADDR))")
>   field(TWV, ".1")
>   field(ASG, "MC_MAINT")
>   field(FOFF, "Frozen")
>   field(PRIO, "HIGH")
>   field(OMSL, "closed_loop")
>   field(RTRY, "0")
> }
>
> My function that triggers synchronized motion
> asynStatus Axis::processDeferredMoves()
> {
>   asynStatus status;
>
>   /*resets controller flag*/
>    status = resetFlags();
>    if(status) goto skip;
>
>   /*sends command to start synchronized motion*/
>    sprintf(pC_->outString_,GOSYNC);
>    status = pC_->writeController();
>
>    skip:
>    setIntegerParam(pC_->motorStatusDone_, 0);
>    setIntegerParam(pC_->motorStatusCommsError_, status ? 1:0);
>    callParamCallbacks();
>    pC_->wakeupPoller();
>    return asynSuccess;
> }
>
> Thanks in advance,
> Jacob

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System