Reading SR400 photon counter buffer at every period

[LBPGroup]

Hello,

We are using a photon counter SR400 with Labview. We had an old code that was working properly on Labview 2010 (on Windows XP), but we have now rewritten a new code in Labview 2018, on a new computer running on Windows 10, to be able to use other equipment together with the photon counter. We are re-using the same DAQ card on the new computer, and interfacing the photon counter through RS-232 port.

In our old code, we used the ET command to read the content of the photon counter buffer. By doing this, we were able to plot the number of counts for each channel at every period (i.e, continuously while measuring).

In our new configuration, we use a similar part of the old code structure and the same ET command to read the buffer. However this time, we can only access the content of the buffer at the end of the full task (i.e. only once, after N periods). Every attempt to read the buffer before N periods gives us as output an empty string, and a red light is flashing on the front panel of the photon counter. 

This is not an error that prevents us from continuing counting, but it is preventing us to monitor the data continuously while measuring (i.e unable to plot it).

Is there a specific configuration of the photon counter that we are missing in order to access the content of the buffer after every period? Because we know by our previous code that it is indeed possible to read the buffer at every period. 

Thank you for help!

[cstorey]

Without sharing any code, I doubt you'll get a solution to your problem.  Are you using the SR400 LabVIEW driver or just GPIB and SCPI commands?  Did the interface change from serial to GPIB/USB/LAN? 

Posting both the old and new code would help at least shed some light on the way you are handling things differently.  Also, usually the act of preparing your code for display leads to the solution...or at least tidier, better code. 😉