Mesh disconnection

RE: Mesh disconnection

Allen96 — Mon, 17 Feb 2020 08:08:02 GMT

Sorry for the late reply,

We got the opportunity to change part of the ground plane and make it more similar to the referenced one.

The result is perfect, the device will automatically reconnect as supposed to be.

Thanks for your help

RE: Mesh disconnection

Kenneth — Mon, 10 Feb 2020 08:38:01 GMT

Changes in (or more specific poor) grounding can lead to the design more prone to noise, for instance from serial interface, this can influence both transmissions, but also reception. So you may want to disable serial interfaces during testing to check if that may be the case.

Best regards,
Kenneth

RE: Mesh disconnection

Allen96 — Fri, 07 Feb 2020 11:22:19 GMT

Hi,

thank you for the information. We are using the module that use an external antenna, the area under the connector is free from copper anyways, the ground plane is not as indicated.

I've read that the changes in ground plane size can effect the power of the transmission, isn't that irrelevant since the signal is received clear before i take the antenna out?

Thanks for your time

RE: Mesh disconnection

Kenneth — Thu, 06 Feb 2020 19:02:18 GMT

Have you checked that you have followed chp 11. RF Design Notes:
https://www.mouser.com/datasheet/2/883/BMD-300-Series-DS-V1.11-1147364.pdf

RE: Mesh disconnection

Allen96 — Wed, 05 Feb 2020 20:53:59 GMT

Hi,

Sorry for the late reply.

The connections that we have done are the following:

- pin number 22 and 24 are used for the USART communication with an STM32

- pin number 43, 44 and 39 are used for the programming

No other pin are used. The module used is the BMD300, without any crystal (I've changed a portion of code about clock settings). We have used only 0.1uF capacitor for decoupling but should be good since the 4.7uF capacitor is included.

If you want i can post the portion of the code where I changed the clock configuration and the pcb design as well.

Thank you for the help.

RE: Mesh disconnection

Allen96 — Wed, 29 Jan 2020 21:50:12 GMT

Hi, thaks for the reply.

In the next days I'll put a list of all the hardware difference.

About the code, i have absolutely no asserts, and in the evaluation board as well in my board, no event are generated when the antenna is removed (which cause a lost connection in the provisioner RSSI information).

Thanks for the fast help

RE: Mesh disconnection

Kenneth — Wed, 29 Jan 2020 12:19:47 GMT

Sounds to me like some hardware issue, e.g. due to difference in hardware, maybe look for floating pins, undefined pins, difference lfclk source, supply voltage, poor grounding, electrical?

Is there no asserts or does it seem as the application is stuck somewhere in code execution?

Kenneth