Server data throughput for Virtual COM port

Hello,

my name is Michele Sardo and I work for a company called STMicroelectronics. We are using VirtualHere in our lab PC (Windows 10) to make remote access to our DUT which are essentially USB Virtual COM Port (to be accurate mbed virtual com ports).

We have a situation where our DUT output 90 bytes every 10 ms and the PC read them.
If we read from the local PC where the USB is attached we can sustain this data rate without any problem.
When we use the same program via VirtualHere, we experience problems of overflow on the DUT and it appear to us as the server is not polling fast enough the DUT to read the data generated.
When the delay reach about 50 ms, the problems seems to disappear.

Any idea on how to improve the data throughput or define the polling rate on the server (if possible) ?

Best Regards

Michele Sardo

#2

VirtualHere doesn't poll for data, it will send/receive data as soon as it is available, there is no waiting. So your network latency must be quite high and causing the issue. When you right click USB Hubs->About->Statistics and run your test, what does the latency graph look like? Is it variable, or is it flat in the 1-2ms range?