RE: Strange Custom Proximity

dtt60 — Wed, 18 Dec 2019 02:11:17 GMT

Hi Kenneth

The ANT display can not receive the sensor when I set the custom proximity threshold to -50dBm today. It seems that the custom proximity is not work for any threshold value and any distance. Would you confirm the custom proximity threshold is workable?

Thanks

RE: Strange Custom Proximity

Kenneth — Tue, 17 Dec 2019 19:33:26 GMT

I don't have any explanation to this, but a few things to check:

I assume you are checking error codes for the various sd-api calls here? In general check out:
https://www.thisisant.com/resources/an12-proximity-search/

The valid range for the RSSI is -20 to -90dBm:
https://infocenter.nordicsemi.com/topic/ps_nrf52840/radio.html?cp=4_0_0_5_19_14_8#unique_1088842021

RSSI is an very inaccurate way of measure distance reliable, since the radiation pattern of antenna and reflections can impact the RSSI by as much as tens of dB.

I am not sure what boards you are using here. Do you see the same if you are using two nRF52840-DK? Have you done any antenna and matching network tuning on "display" and "sensor"?