VI_ERROR_TMO (-1073807339) when printing buffer data

[vuhoang8]

I'm currently writing a script for a pulse train on the Keithley 2612B and have run into a timeout error when attempting to print the readings from the two designated buffers.

I created the buffers using the code below:

smua = inst.commands.smu["a"]
    
ibuffer = inst.commands.buffer_var["smua.nvbuffer1"]
vbuffer = inst.commands.buffer_var["smua.nvbuffer2"]
    
inst.commands.reset()
    
ibuffer.clear()
ibuffer.appendmode = 1
ibuffer.collecttimestamps = 1
    
vbuffer.clear()
vbuffer.appendmode = 1
vbuffer.collecttimestamps = 1

Afterwards, I created the pulse train using an example adapted from the 2600B Reference Manual, page 3-49. However, when I run the following code:

inst.print_buffers("smua.nvbuffer2.readings", "smua.nvbuffer1.readings")

I get the timeout error. Does anyone have any idea what is going wrong here? I was able to print fine from the buffers when I ran a continuous DC sweep, so I suspect there may be something in the trigger model I've written. Happy to share any code if needed.

[amccann-Tek]

Hi @vuhoang8 Sorry for the delayed response. Do you still need help with this issue?

[vuhoang8]

Hi! Unfortunately, I am. This is what my terminal looks like when the error occurs:

  File ~\Environments\venv\Lib\site-packages\tm_devices\drivers\pi\pi_device.py:400 in query
    response = self._visa_resource.query(query).strip()

  File ~\Environments\venv\Lib\site-packages\pyvisa\resources\messagebased.py:647 in query
    return self.read()

  File ~\Environments\venv\Lib\site-packages\pyvisa\resources\messagebased.py:485 in read
    message = self._read_raw().decode(enco)

  File ~\Environments\venv\Lib\site-packages\pyvisa\resources\messagebased.py:441 in _read_raw
    chunk, status = self.visalib.read(self.session, size)

  File ~\Environments\venv\Lib\site-packages\pyvisa\ctwrapper\functions.py:2336 in read
    ret = library.viRead(session, buffer, count, byref(return_count))

  File ~\Environments\venv\Lib\site-packages\pyvisa\ctwrapper\highlevel.py:226 in _return_handler
    return self.handle_return_value(session, ret_value)  # type: ignore

  File ~\Environments\venv\Lib\site-packages\pyvisa\highlevel.py:251 in handle_return_value
    raise errors.VisaIOError(rv)

VisaIOError: VI_ERROR_TMO (-1073807339): Timeout expired before operation completed.


The above exception was the direct cause of the following exception:

Traceback (most recent call last):

  File ~\Environments\venv\Lib\site-packages\spyder_kernels\py3compat.py:356 in compat_exec
    exec(code, globals, locals)

  File c:\users\peem\environments\venv\workspace\pulsed sweep\pulsed_script2.py:131
    pulsed_sweep(smu)

  File c:\users\peem\environments\venv\workspace\pulsed sweep\pulsed_script2.py:117 in pulsed_sweep
    inst.print_buffers("smua.nvbuffer2.readings", "smua.nvbuffer1.readings" )

  File ~\Environments\venv\Lib\site-packages\tm_devices\drivers\pi\tsp_device.py:172 in print_buffers
    buffer_data = self.get_buffers(*args)

  File ~\Environments\venv\Lib\site-packages\tm_devices\drivers\pi\tsp_device.py:124 in get_buffers
    buffer_str = self.query(f"printbuffer(1, {buffer_size_name}.n, {buffer_name})")

  File ~\Environments\venv\Lib\site-packages\tm_devices\drivers\pi\pi_device.py:406 in query
    raise visa.Error(msg) from error

Error: The query failed with the following message: VisaIOError('VI_ERROR_TMO (-1073807339): Timeout expired before operation completed.')

[amccann-Tek]

I am not an SMU expert, and as I try to find one to support in detail I think I have an idea:

And keep in mind the SMU model you are using is not fully complete.

I believe the printbuffer command you are looking for is not actually equivalent to print_buffers and might not be implemented correctly or completely at this time.

Does inst.commands.printbuffer() method do what you are looking for?

[vuhoang8]

Unfortunately, I get the timeout again when I use inst.commands.printbuffer() as follows:

    inst.commands.printbuffer(1, NUM_PULSES, "smua.nvbuffer2.readings")
    inst.commands.printbuffer(1, NUM_PULSES, "smua.nvbuffer1.readings" )

In this case, NUM_PULSES is set to 10. I'm wondering if I've set up the trigger model incorrectly, since inst.print_buffers() had worked when I used it in a continuous sweep script without a trigger model. At the moment, I've set up the measurement in this case like so:

    smua.trigger.measure.iv("smua.nvbuffer1", "smua.nvbuffer2")
    smua.trigger.measure.action = 1
    smua.trigger.measure.stimulus = period_timer.EVENT_ID
    smua.measure.rangei = 0.1

[amccann-Tek]

@vuhoang8 I think the best approach at this point would be to open up an official support ticket

That is where most of our support engineers reside and will get you assigned to some SMU experts. Let me know if you do not hear back from someone in a timely manner.

[vuhoang8]

Noted - thank you for your help and guidance!

[vuhoang8]

The issue has been resolved. In my script, I was setting attributes like so:
smua.trigger.source.stimulus = period_timer.EVENT_ID

However, to properly set them, you must set them as strings:
smua.trigger.source.stimulus = "period_timer.EVENT_ID"

[amccann-Tek]

Thanks for following up and I am glad you got the problem sorted out.

I am the Product Manager for this package at Tek so let me know if you have any other issues, or suggestions for improving it.