Triggering analog measurements with quadrature encoder

[consig]

I am trying to acquire in-cylinder pressure data from an internal combustion engine using a PCI 6036e hooked up to an SCB-68.  The encoder and pressure tranducer seem to be working, but I'm having problems synchronizing a pressure measurement with a trigger from the encoder.  I'm using 'Measure Angular Position.vi" as a starting point, and then included a DAQ Assistant within the case structure to acquire pressure.  I'm graphing the pressure trace against the angle that is calculated by the vi, but it seems as if the waveform can't keep up with the engine.  Is there a better way to trigger the measurement or synchronize it so that the angle and pressure measurements can be graphed at the same time?  I'd like to sample at 500kHz.

[Hillman]

Hi Consig,

I have an example which synchronises an AI (Temperature) and a Coutner Task (Quad Encoder) - see attachment. This vi also saves the data to a file text file.

So when the enocder position changes, this vi acquires and records the data of both tasks into the text file. 

If the rate is faster than the loop rate some sort of queue maybe required, but I wouldn't have thought so.

Let me know what you think!

Regards,