nRF52840 dongle communications very slow in Windows

[Hanowar123]

Hi All,

I have a system with an nRF52840-dongle (PCA10059) acting as a serial port in windows 10. It runs extremely slowly. Sending 8kB over the interface takes 3 minutes.

Is there any way in Windows to adjust memory allocation, or see why the driver is running so slow?

The system is used for testing hundreds of bluetooth units, resulting in huge wasted time.

Thanks,

Rob.

[Hanowar123]

Hi Edvin,

I am on holiday this week but will forward those questions to the windows software people when I get back.

In the embedded code I set the MTU (transfer length) to 247 bytes. So it gets the data in fairly long messages. I have limited control as the PC side software is (politically) difficult to change as it was written by someone outside my group. From what he told me the windows side 'promises' the right number of bytes, and this maybe where the bottleneck is happening.

What maybe causing the problem is the embedded device has a Telit BlueMod+S50 module. I assumed (which is lethal) that having the same BT chip both ends of the chain would be most reliable.

Rgeards,

Rob.

[Edvin]

Hello Rob,

Without knowing more about how the application is running, it is difficult to say what the bottleneck can be. You can try a simple USB CDC application:

NCS\zephyr\samples\subsys\usb\cdc_acm, and you should see that you don't have that same bottleneck our of the box with a CDC application, so I would guess that the limiting factor is elsewhere.

Have a nice vacation

Best regards,

Edvin