LabVIEW FPGA FIFO Read

[LullabyIsland]

Hello Guys,

I have a question about FPGA FIFO Read. In our application, the FIFO Output is to control the speed of a motor. I am using FIFO because I need to control the execution time and the speed of the motor.

The question is , say I load 100 elements in FIFO from host and FIFO starts outputting the value- no problem here. But I have a problem with the status of FIFO element after FIFO Read. what should be the final value of the element? Should it be 0 or the final value of the array? I am confused, because the final value of the element is the final value of the array. 

I thought it would go to 0 because FIFO is completely read. Right? 

Thanks,

L

[Intaris]

No, it's important to monitor the output of the FIFO to make sure you adapt for whent he FIFO is empty, it simply returns the last value when empty.  I've run into this a couple of times.  This is the most efficient way to implement it on FPGA, but I admit is seems a bit random.

TL,DR : Always check the "Timed Out" output of your FIFO and handle accordingly.

[LullabyIsland]

Yeah. Actually I do check the timeout. I just wanted to confirm I am not doing any mistakes with the configuration or something.

Thanks mate.