NI PXIe-6345 digital signal edge detection

[skinnyLiam]

Im trying to detect the falling edge of the digital signal coming in Dev1/port0/line0 of NI-6345 using NIDAQMX python library.

This is my code snippet

    with nidaqmx.Task() as task:
        channel=task.di_channels.add_di_chan(channel)
        task.timing.cfg_change_detection_timing(rising_edge_chan="/Dev1/port0/line0",
                                                falling_edge_chan="/Dev1/port0/line0",
                                                sample_mode=AcquisitionType.CONTINUOUS)

        start=time.time()
        while True:
            sample= task.read()
            print(f"Falling edge detected: {sample}")
            break
        difftime= time.time()-start
        print("difftime=",difftime)   

but I'm getting the following error

Traceback (most recent call last):
  File "/home/user/measurePulse.py", line 201, in <module>
    waitUntilSignalTransition()
  File "/home/user/measurePulse.py", line 95, in waitUntilSignalTransition
    sample= task.read()
  File "/home/user/.pyenv/versions/3.10.7/lib/python3.10/site-packages/nidaqmx/task/_task.py", line 623, in read
    _, samples_read, _ = self._interpreter.read_digital_lines(
  File "/home/user/.pyenv/versions/3.10.7/lib/python3.10/site-packages/nidaqmx/_library_interpreter.py", line 4541, in read_digital_lines
    self.check_for_error(error_code, samps_per_chan_read=samps_per_chan_read.value)
  File "/home/user/.pyenv/versions/3.10.7/lib/python3.10/site-packages/nidaqmx/_library_interpreter.py", line 6408, in check_for_error
    raise DaqReadError(extended_error_info, error_code, samps_per_chan_read)
nidaqmx.errors.DaqReadError: A hardware failure has occurred. The operation could not be completed as specified.

Task Name: _unnamedTask<0>

Status Code: -50152

I'm a bit new with NI cards, and I couldn't figure out if the NI6345 digital lines can detect edges.

Any help on this matter is greatly appreciated

[santo_13]

What do you want to do after detecting the falling edge?

[skinnyLiam]

I wanted to detect the falling edge of the signal and return from this function.

[santo_13]

So, you need a way to detect a digital edge transition to proceed/do something in software.

[skinnyLiam]

Exactly