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Boolean toggle within timed flat sequence.

Dear all,

 

Tried resolving this issue for the past few hours with no luck. I have built a VI to control a peristaltic pump and digital valve for a microfluidic setup. The user can define a sequence of operations that are automatically processed once the user presses start.

 

I have implemeneted a state machine whereby one of the states has a for-loop to unbundle an array (sequence) of clusters (settings). Within this for-loop I then have a flat sequence to ensure that the valve and pump are setup correctly before engaging the pump. 

 

I would also like the user to be able to select/deselect a 'recirculate' function whereby the pump oscilates between forward and reverse (maybe at a user defined rate, but 0.2 Hz should be fastest).  This is so that when we have very small volumes of an important sample we can maintain some sort of flow without losing the sample to waste.

 

I cannot seem to get this to work. I tried a shift register, using a digital waveform, etc.

 

Any suggestions would be welcomed.

 

Kindest regards,

 

Jules

 

 

 

 

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First of all, don't use a sequence structure, use data dependency on error clusters. Second get rid of the express VIs. They are inefficient and hide setups. Third, the digital IO: Is it all on the same port? If so, a port write is more efficient.

Mike...

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