Hello,
I’m new to instrument control and I am using an old code from my lab to try and get data out of a measurement setup and the sampling rate is much slower than what I would expect.
Our setup involves an infrared detector connected to a Tektronix 754D oscilloscope which uses a Prologix GPib-usb controller (v. 6.1.4) to connect to a PC using a labview VI (see attached). The maximum sampling rate that I’ve been able to achieve using this setup seems quite limited – only about 8-10 measurements per second or 10 Hz. Given the baud rate of the controller (9600), I believe this number should be much higher. The number of bytes being written from one measurement are 19 or so. While I don’t understand why that’s so high – a single “double” would only be 8 bytes and we don’t even end up with that much precision – even at 20 bytes, if we have 9600 baud we should probably be seeing 60 Hz if 1 byte = 8 bits (right?).
When I segment and time test my code, as I do in the attached VI, the bottleneck seems to be isolated at the “read serial” portion of the code since that portion takes ~100 ms. I was hoping someone might know what this bottleneck could be and if there is a way of achieving faster measurement sampling.
If it’s a hardware thing, what would be a good direction to speed things up? Perhaps replacing the controller? I saw something about a “scope card” on something similar: (https://forums.ni.com/t5/Instrument-Control-GPIB-Serial/sample-rate-problems/m-p/721997#M30346)
Many thanks!
