Timeout when using Merlin

[GearoidM]

Hello,

I am getting the following error after running Instamatic on a Merlin detector for a short time ( < 5 minutes).

Exception in thread Thread-2:
Traceback (most recent call last):
File "c:\users\merlin\appdata\local\programs\python\python38\lib\threading.py", line 932, in _bootstrap_inner
self.run()
File "c:\users\merlin\appdata\local\programs\python\python38\lib\threading.py", line 870, in run
self._target(*self._args, **self._kwargs)
File "c:\users\merlin\appdata\local\programs\python\python38\lib\site-packages\instamatic\camera\videostream.py", line 56, in run
frame = self.cam.getImage(exposure=self.frametime, binsize=self.binsize)
File "c:\users\merlin\appdata\local\programs\python\python38\lib\site-packages\instamatic\camera\camera_merlin.py", line 196, in getImage
framedata = self.receive_data(nbytes=self._frame_length)
File "c:\users\merlin\appdata\local\programs\python\python38\lib\site-packages\instamatic\camera\camera_merlin.py", line 86, in receive_data
data.extend(self.s_data.recv(nbytes - len(data)))
socket.timeout: timed out

[stefsmeets]

Thanks for report! When acquiring data using software trigger, I set Merlin to collect 10k frames:

instamatic/instamatic/camera/camera_merlin.py

Lines 141 to 143 in 5397b11

	# Set NUMFRAMESTOACQUIRE to a large number
	# Merlin will only collect this number of frames with SOFTTRIGGER
	self.merlin_set('NUMFRAMESTOACQUIRE', 10_000)

I think you may be hitting this number, after which Merlin will no longer send frames and the command needs to be refreshed. Changing the exposure time will reset the acquisition, and also the frame counter. Does this sound possible?

[stefsmeets]

I added a check that tracks the frame number and resets when the number of frames to acquire gets hit. I will test and merge it on Friday.

[GearoidM]

Yeah, that seems to be what is happening. The timeout occurred at around 8.35 minutes for a 0.05 s exposure time. So that's about 10000 frames. I then tested changing the exposure time and Instamatic did not timeout after this, implying the counter was reset by this action. I think your check should solve this issue, then. Thanks!

[stefsmeets]

I set the number to the maximum value of 42949672950. This means you can collect for over a year with continuous 1 ms exposures to hit the limit 😅