problem with elapsed timer sub vi - RPM data

[c ryan]

I'm trying to find RPM of a motor using a proximity sensor connected to my cRIO 9012, module 9205.  I'm using the Elapsed Timer sub vi in order to find the amount of time between pulses of the prox sensor.  My issue is that it doesn't seem to reset every time there is a pulse, only sometimes.  The pulse is boolean and is connected to the reset terminal for the Elapsed Timer.  The pulses happen quickly, maybe around a tenth of a second, yet the elapsed timer gets up to a second or more before it resets.  

Can anyone help me here? I'm somewhat new to Labview and am having a lot of trouble learning the FPGA stuff.  I got thermocouples working, but can't get RPM working.  If anyone can think of a better way to find RPM, any help is welcome.  Please take a look at my code and tell me if I'm doing anything wrong for FPGA usage.  

Thanks!

[Blayne_K · Accepted solution]

Hello Ryan,

I think you might benefit from taking a look at the following link which is an example of tachometer implemented on a cRIO with Labview FPGA http://zone.ni.com/devzone/cda/epd/p/id/2326. The example is configured with a NI 9234, but you should be able to use your 9205 as an alternative to that module.

Regards,

Blayne Kettlewell

ELP Engineer

National Instruments  

[c ryan]

The code from tha example worked great! thanks a lot