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<== Date ==> <== Thread ==>

Subject: seq and synchronous writes
From: "Konrad, Martin" <[email protected]>
To: "[email protected]" <[email protected]>, "[email protected]" <[email protected]>
Date: Thu, 5 Sep 2013 19:54:51 +0000
Hello,
I am using a state machine to control a motor setup. In each step it 
basically sends a command to the motor record and waits for it to 
complete. This can be detected by the "done moving" field (DMOV).

Here is how I implemented this:

state1 {
   entry {
     sprintf(stateMsg, "state 1");
     pvPut(stateMsg);
   }

   when(foo) {
     motor = bar;
     pvPut(motor, SYNC);
   } state state2
}

state2 {
   entry {
     sprintf(stateMsg, "state 2");
     pvPut(stateMsg);
   }
}

Unfortunately this leads to a long delay between the motor starting to 
move and the update of the status message (sometimes 10 seconds!).

I suspect I'm using sequencer the wrong way here. Are synchronous pvPuts 
necessary to make sure the command has been send to the motor record? 
Should I move the pvPut line to the end of the entry block of state2? 
Are there some best practices how to keep the state machine code clean 
and readable?

Thanks,

Martin


Replies:
Re: seq and synchronous writes Pete Jemian
RE: seq and synchronous writes Mark Rivers
RE: seq and synchronous writes Mooney, Tim M.

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