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FPGA target NI 9146 publishing user-defined variables to a network

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I am currently developing code to use on the NI 9146 ethernet expansion chassis with 3 modules hooked up, NI 9205, NI 9264, and NI 9476.


The code is suppose to be downloaded onto the chassis as FPGA code and for the chassis to run the code by itself and output the information on the network it is hooked up into.  The code is simple (measuring voltages of pressure readings and converting them to Pressure).


When the code is on the Host pc it can be run through the target and runs successfully.  The there parts are just have thing chassis User FPGA 1 LED blink a few times a second, convert voltage into pressure and output a variable on the network, and read a few boolean variables that are on the network.  All of the variables do appear on the network when run this way (pressing the run button of a compiled FPGA VI from the host PC)


When the FPGA VI is downloaded onto the chassis flash memory, set to run when downloaded and on device reboot, the FPGA VI runs, because the User FPGA 1 LED blinks at the rate specifided in the code, but the variables do not get put onto the network.


Attached are several screen shots of the code and project window.


Thank you for your time



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Accepted by topic author MWorner



The FPGA cannot write to variables by itself.  It is usually used to do some high speed task.  In order to communicate with a host PC, you will need some code running on the controller that uses the FPGA Interface VIs.

-Jim B
Applications Engineer, National Instruments
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