RSSI value of 127?

[rshankle]

Hi All,

Sanity check here.  I'm reading the RSSI value from a received packet

if (nrf_esb_read_rx_payload(&rx_payload) == NRF_SUCCESS)
{
    if (rx_payload.length > 0)
    {
        i8WMSB_RSSI = rx_payload.rssi;
        esb_received_data = true; // we don't want to do much in this interrupt service routine. We will process data in main or elsewhere.
    }
}

Every so often I'm getting a value of 127.  Does this mean anything?   (I'm looking through my code to see what might be causing that but wanted to check.)

thanks!

Bob

[Sigurd]

Hi,

I suspect it's caused by interference , reflections/multi-paths, etc

[rshankle]

I thought the "lowest" RSSI would be around 101 or so.   How is it even detecting the signal if 127 really represents -127dBm?   (I was hoping 127 or 0x7F was a flag to represent some error condition.)

I would also expect random numbers between 101 and 127 but nothing shows up in that range.

[Sigurd]

The RSSISAMPLE can hold values in the range of [0..127] in theory, but the stated accuracy of ±2 dB is only valid in the range -90 to -20, so you can consider a reading at -127 as non-valid.

[rshankle]

thanks.  I'll ignore the reading if 127.

Bob