Use angular Encoder position to trigger Digital out

Hi,
I am a beginner labview user, I have access to three modules, two NI9201 and one NI9401.
I have an angular encoder that is used to measure the angular position of a motors crankshaft, what I'm trying to do is use the encoder to trigger a digital out (spark event in the engine) at a certain angular position. For example, I would like to trigger at top dead center (or 0 degrees on the encoder), then I want to be able to change this to +5 degrees on the encoder, etc.
So far I am able to read in the angular encoder when the motor is running, I am also able to output digital out signals although I can't find a way to link the two together.
If anyone has any idea how to do this, it would be greatly appreciated, I have attached my VI.
Thanks in advance,
Nick
Solved!
Go to Solution.
Attachments:
Encoder_Spark.vi ‏40 KB
Encoder_Spark.vi ‏40 KB

Hi Nick,
I hope the attached vi will get you on track. It's just a general concept.
The while loop will run until you hit the stop button.
   I take it you will need one spark per revoultion.
This VI is really just an If/Then
   If the encoder value is equal to (in this example ) zero,
   Then trigger the digital output.
I know I have a broken wire, but I didn't know how to get the angular position from you DAQmx.
Let me know if this help. (Also let me know if I'm off target)
Good luck,
Bill
Attachments:
Trigger spark concept.vi ‏9 KB

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melvinfeng wrote:
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