PicoScope 7 Software
Available on Windows, Mac and Linux
Streaming mode, increase update frequency
Streaming mode, increase update frequency
Hi!
We use a PicoScope 5443D to record a signal in streaming mode. Our C programm collects the data via a callback function through ps5000aGetStreamingLatestValues(). The data is then processed in a FFT-analysis. Everything works fine so far.
Since we plot the FFT-data in real-time, we optimized the code for a high frame rate, only to find out, that we are limited by the update rate of the PicoScope device (or driver). Most of the times we call ps5000aGetStreamingLatestValues() our Callback function is not processed. The callback function will be called quite exactly 15 times a second. The size of the returned data is always the same. We tried several changes in the code, but the 15Hz didn't change.
In the manual for the streaming mode we could find: "Memory segmentation. The memory can be divided into segments to reduce the latency of data transfers to the PC.". We did try to segment the memory, even with high numbers, but there was no change to the frequency.
Is it possible to change the frequency the chunks of data are provided to the callback function or is this somehow hardcoded?
Thanks for any help,
Werner
We use a PicoScope 5443D to record a signal in streaming mode. Our C programm collects the data via a callback function through ps5000aGetStreamingLatestValues(). The data is then processed in a FFT-analysis. Everything works fine so far.
Since we plot the FFT-data in real-time, we optimized the code for a high frame rate, only to find out, that we are limited by the update rate of the PicoScope device (or driver). Most of the times we call ps5000aGetStreamingLatestValues() our Callback function is not processed. The callback function will be called quite exactly 15 times a second. The size of the returned data is always the same. We tried several changes in the code, but the 15Hz didn't change.
In the manual for the streaming mode we could find: "Memory segmentation. The memory can be divided into segments to reduce the latency of data transfers to the PC.". We did try to segment the memory, even with high numbers, but there was no change to the frequency.
Is it possible to change the frequency the chunks of data are provided to the callback function or is this somehow hardcoded?
Thanks for any help,
Werner
Re: Streaming mode, increase update frequency
Can you provide your code, either here or to support@picotech.com , so that we can take a look at how you have setup the scope and how you are collecting and processing the data.
Martyn
Technical Support Manager
Technical Support Manager
Re: Streaming mode, increase update frequency
Hi Martyn, I sent you the source code. I'll post the resolution to this problem, if there is any.
Regards,
Werner
Regards,
Werner