I can only receive Labview interrupts on falling edge

I have a distance/object detector that goes low when something is detected in range.
When I set rising edge false and falling edge true, I get interrupts.
When I set rising edge true and falling edge false, I don’t get any interrupts.
Reading the DI, I get changes of state as expected.
I put a scope on the line and the signals are going between 4.8 and 0 volts.
Any suggestions?

Could you provide more details on

  1. The model of the sensor
  2. How it is wired to the roboRIO
  3. The code you’re running
  4. What you mean by “interrupts”

Screenshots and pictures are welcome.

Looks like we had the same issue in 2019:
image

Only work around we had was to only use falling edge.

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That’s interesting. Both edges work from text based languages, so its not an fpga bug. Must be a labview side library bug somewhere. Interesting nobody ever noticed it before.

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Thanks for the response.
Can you report this to the LabView developers or point me to the bug report system?

Done.

Thanks for the response.
I have a boy who is good with hardware. I’ll give him a REV MXP development board and a 74ALS04 and tell him to figure it out.
The electronics store can’t remember the last time that they sold a 74 series part.

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