PSoC™ 4 Forum Discussions

[EyGe_3183606]

Hello,

We have a PSOC 4 MCU and we are using it as a peripheral. 

We are trying to measure the RSSI with the function CyBle_GetRssi after we are connected to our BLE dongle (using CySmart 1.3). 

It is very unstable and usually, it gives completely unreliable data going all over the range and even exceeding the given range of -85 to 5 db. 

In rare cases, it gives the correct data but once we move our device it suddenly stops becoming accurate and data that is completely unrelated gets printed all the time. 

Our code is fairly simple. Every second (once we are connected) we do the following:

int8_t scRSSI = CyBle_GetRssi();
uint8_t ucRSSI = scRSSI*(-1);
iprintf2_ISR(True,E_DEBUG_CODE,"[BLE] ### RSSI : -%d, %x",ucRSSI, scRSSI);

Here is the type of data that we get (as an example):

01/01 00:00:09.967 [BLE] ################# RSSI: -141, 73

01/01 00:00:11.009 [BLE] ################# RSSI: -49, ffffffcf

01/01 00:00:12.010 [BLE] ################# RSSI: -219, 25

01/01 00:00:13.013 [BLE] ################# RSSI: -57, ffffffc7

01/01 00:00:13.977 [BLE] ################# RSSI: -142, 72

01/01 00:00:15.009 [BLE] ################# RSSI: -50, ffffffce

01/01 00:00:15.980 [BLE] ################# RSSI: -43, ffffffd5

01/01 00:00:16.970 [BLE] ################# RSSI: -43, ffffffd5

01/01 00:00:17.972 [BLE] ################# RSSI: -213, 2b

01/01 00:00:19.008 [BLE] ################# RSSI: -206, 32

01/01 00:00:19.978 [BLE] ################# RSSI: -22, ffffffea

01/01 00:00:21.007 [BLE] ################# RSSI: -192, 40

01/01 00:00:22.009 [BLE] ################# RSSI: -100, ffffff9c

01/01 00:00:23.012 [BLE] ################# RSSI: -8, fffffff8

01/01 00:00:24.007 [BLE] ################# RSSI: -92, ffffffa4

01/01 00:00:25.010 [BLE] ################# RSSI: -6, fffffffa

01/01 00:00:26.008 [BLE] ################# RSSI: -91, ffffffa5

01/01 00:00:26.978 [BLE] ################# RSSI: -175, 51

RARELY it is reliable like here (which matches the RSSI measurement in the CySmart 1.3 program): 

01/01 00:00:16.008 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:17.007 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:18.014 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:18.979 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:20.008 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:20.973 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:22.007 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:23.012 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:24.007 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:25.006 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:26.007 [BLE] ################# RSSI: -34, ffffffde

01/01 00:00:27.007 [BLE] ################# RSSI: -34, ffffffde

Any idea why this is completely unreliable?

Thanks,

Eyal