PXIe 7841R Led blinken

[asmbeth]

Hallo every body,

Iam new in Labview FPGA, also i have simulated the PXIe 7841R and i want to generate a square pulse with a bandwidth of 1ms and a periode of 2ms.

for that i used a while loop and in the while loop a flat sequence with 4 compartements:

1c-I used a digital IO port and i wrote a True in it

2c-I use a Wait component with a constant =1ms

3c-I used the same digital IO port and i wrote a false in it

4c-I use a Wait component with a constant =2ms

i also attached a LED to the input of the DIO at 1c and a local variable of the same LED to the input of the DIO at 2c .

The result shows a blinkinf LED with a high takt not respecting the timin i gave.

wenn i use the debugging tool of labview which causes a small delay i see the wanted result.

So i think the problem ist that the loops run with the board frequency which is 40 Mhs or 25 ns very quick as the entended timing.(Iam not sure 😞 )

can you plz help me?

Thx.

[altenbach]

Please show us some code. How do you determine that the loop does not run at 1+2ms. This is probably too fast to see by eye.

Why do you think you need all that duplicate code?

[asmbeth]

I will do it tomorrow, because iam not at my office any more.
I know that the loop does not run properly because i also tried with time =some seconds with a high difference between the high and the low pegel an it is always showing a very fast blinking LED.

I will upload the project tomorrow.
Thx

[asmbeth]

Hi every body,

here is a pic of my code.

i just want to generate a square pulse.

you can also give me better ideas, because as i said am new in Labview and Labview FPGA.

thx a lot 🙂

[Duffy2007]

Hello asmbeth,

directly verify timing on windows with simulated hardware is not working.

Here some help for debugging FPGA code

Testing and Debugging LabVIEW FPGA Code

Using the LabVIEW FPGA Desktop Execution Node

Hope it helps.

[asmbeth]

Hello Duffy2007,

Thx for you answer, i had a look on the both articles, they are very informativ.

But i really need help creating a square pulse, du you know any idea how kann do this?

thx a lot.

[Duffy2007]

Hello asmbeth,

your code should working.