nRF52832 get composition data very slow

[John Smith]

Hi I programmed the nRF mesh experimental dimming example on the nRF52832 chip. I noticed that, when using Bluetooth Mesh provisioning apps (I've tried several to verify this behavior), it takes a lot of time for me to get the composition data from the nRF52832 chip. I have run bluetooth mesh examples on a Silicon Labs Thunderboard Sense 2, and, in comparison, the Thunderboard Sense 2 gets the composition data almost instantly after request from the app. Is this a well known behavior from the nRF52832 chip? If so, are there any chips that are as fast as the Silicon Labs chip?

Thanks for the help.

[Hung Bui]

Hi John, 

Could you capture a sniffer trace when doing provisioning with the Silicon Lab board ? 

We would want to compare it to the provisioning trace when doing the same with the nRF52. How long it usually take to provision the nRF52 with your phone ?

The provisioning time depends largely on: 

- Advertising interval (how fast the phone can establish a connection to the device)

- Connection interval (how fast the data is transferred between the phone and the device)

- Is there any dead period that the phone wouldn't do anything. 

What you can do to test is to increase the preferred connection interval in nrf_mesh_config_examples.h 

Try changing MIN_CONN_INTERVAL to 7.5 and MAX_CONN_INTERVAL to 15ms you should see some improvement. 

However, the draw back of this is that the time domain for mesh will be affected and the mesh performance will be degraded when a phone connected to the device. So the longer connection interval should be used after the provisioning finished. By default in our configuration it's 150ms. 

 

[John Smith]

Thanks for the response. Unfortunately, changing this setting did not change the performance. I actually downloaded a zephyr ble mesh project onto the device, and the performance is very good. Instantaneous connections and transmissions between the iphone and the device. 

Do you guys not recommend using zephyr project? Is zephyr project different than your sdk?

[Hung Bui]

Hi John, 
Could you help taking a sniffer trace ? 
We have some improvement in the provisioning time in our SDK v4.0 . Have you used SDK v4.0 ? How long did it take to finish a provisioning process for you ? 

Zephyr mesh stack is not from us and we can't really say much about that stack. The implementation is totally different from our stack. You may not be able to use the softdevice with the zephyr stack.