BLE Server Get RSSI, MAC, Name etc

[TheUruguayo]

Hello everyone,
I want to do something that seems really elemental to a server, but at this point I'm not available to do.
I want my BLE server to report, the RSSI, MAC and name of connected devices (first 2 most of all). The scan is not good for me, I need to know which ones are connected.
It seems that the function get RSSI is implemented in the client side (which I don't need) is there a way of doing this. I've seen a post that does the following (#893), but is not working for me, the values of that gives are apparently random, (RSSI and MAC, are very different from the scan).
I want to call a function, lets say myserver.getRssi() or simply getRssi(), and have the RSSI and mac of a device connected to me. At this stage only one client is connected. I do not understand how this libraries work yet, and how to move functions around, so any tips on that regard will be appreciated.
(I'm working on a robot that follows this signal).

#include <BLEUtils.h>
#include <BLE2902.h>
#include <BLEScan.h>

String valor;
int aleatorio1;
int aleatorio2;
String alea1;
String alea2;
String alea3;

#define SERVICE_UUID "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"

//para el servicio 2
#define SERVICE2_UUID "45ecddcf-c316-488d-8558-3222e5cb9b3c"
#define CHARACTERISTIC2_UUID "4a78b8dd-a43d-46cf-9270-f6b750a717c8"

int data;
int LED_BUILTIN = 2;
bool deviceConnected = false;
int CUTOFF = -60;

class myServerCallback : public BLEServerCallbacks {

void onConnect(BLEServer* pServer, esp_ble_gatts_cb_param_t *param) {

char remoteAddress[18];

sprintf(
  remoteAddress,
  "%.2X:%.2X:%.2X:%.2X:%.2X:%.2X",
  param->connect.remote_bda[0],
  param->connect.remote_bda[1],
  param->connect.remote_bda[2],
  param->connect.remote_bda[3],
  param->connect.remote_bda[4],
  param->connect.remote_bda[5]
);

ESP_LOGI(LOG_TAG, "myServerCallback onConnect, MAC: %s", remoteAddress);
Serial.println("onConnect");
Serial.println(remoteAddress);
deviceConnected = true;

}

void onDisconnect(BLEServer* pServer, esp_ble_gatts_cb_param_t *param) {

char remoteAddress[20];

sprintf(
  remoteAddress,
  "%.2X:%.2X:%.2X:%.2X:%.2X:%.2X",
  param->disconnect.remote_bda[0],
  param->disconnect.remote_bda[1],
  param->disconnect.remote_bda[2],
  param->disconnect.remote_bda[3],
  param->disconnect.remote_bda[4],
  param->disconnect.remote_bda[5]
);

ESP_LOGI(LOG_TAG, "myServerCallback onDisconnect, MAC: %s", remoteAddress);

deviceConnected = false;

}
};

class MyCallbacks: public BLECharacteristicCallbacks {
void onWrite(BLECharacteristic *pCharacteristic) {
std::string value = pCharacteristic->getValue();

if (value.length() > 0) {
    valor = "";
    for (int i = 0; i < value.length(); i++){
      // Serial.print(value[i]); // Presenta value.
      valor = valor + value[i];
    }

    Serial.println("*********");
    Serial.print("valor = ");
    Serial.println(valor); // Presenta valor.

    if(valor == "off") { //esto puede ser moverse adelante por ejemplo
     digitalWrite(LED_BUILTIN, LOW); 
     Serial.println("LED turned on OFF");
    pCharacteristic->setValue(alea1.c_str()); // Pone el numero aleatorio
      }
    if(valor == "on") {
      digitalWrite(LED_BUILTIN, HIGH); 
     Serial.println("LED turned on");
    pCharacteristic->setValue("LED turned on"); // Pone el numero aleatorio
      }
    if(valor == "r") {
      pCharacteristic->setValue(alea3.c_str());
     
            
    
    }//en if 
  }
}

};
static void my_gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t* param) {

Serial.print("RSSI status");
Serial.println(param->read_rssi_cmpl.status);
Serial.print("RSSI ");
Serial.println(param->read_rssi_cmpl.rssi);
Serial.print("Address ");
Serial.println(BLEAddress(param->read_rssi_cmpl.remote_addr).toString().c_str());
}

void setup() {
Serial.begin(115200);
pinMode (LED_BUILTIN, OUTPUT);//pin y su salida

BLEDevice::init("Hide&Seek");// nombre del dispositivo bl
BLEServer *pServer = BLEDevice::createServer(); // Create the BLE Server
BLEService *pService = pServer->createService(SERVICE_UUID);
BLECharacteristic *pCharacteristic = pService->createCharacteristic(
CHARACTERISTIC_UUID,
BLECharacteristic::PROPERTY_READ |
BLECharacteristic::PROPERTY_NOTIFY |
BLECharacteristic::PROPERTY_WRITE
);
pServer->setCallbacks(new myServerCallback());
pCharacteristic->setCallbacks(new MyCallbacks());

BLEDevice::setCustomGapHandler(my_gap_event_handler);

pCharacteristic->setValue("Iniciado.");
pCharacteristic->addDescriptor(new BLE2902());
pService->start();

BLEAdvertising *pAdvertising = pServer->getAdvertising();

pAdvertising->start();

}

void loop() {

delay(1000);
aleatorio1 = random(1,50); // Crea el numero aleatorio.
alea1 = (String) aleatorio1; // Lo convierte en String.aleatorio
aleatorio2 = random(100,200); // Crea el numero aleatorio.
alea2 = (String) aleatorio2; // Lo convierte en String.aleatorio
//alea3 = alea1 + "," + alea2;

// BLEScan *scan = BLEDevice::getScan();
// scan->setActiveScan(true);
// BLEScanResults results = scan->start(1);
// int best = CUTOFF;
// Serial.print("---------NUEVO ESCANER-------------------- ");
// Serial.print('\n');
// for (int i = 0; i < results.getCount(); i++) {
// BLEAdvertisedDevice device = results.getDevice(i);
//
// int rssi = device.getRSSI();
// if ("Pixel 3a XL"==device.getName()) {
// alea3=device.getName().c_str()+(String)device.getRSSI();
// }
// Serial.print("----------------------------- ");
// Serial.print('\n');
// Serial.println(device.getName().c_str());
// Serial.println((String)device.getRSSI());
// Serial.println(device.getAddress().toString().c_str());
// Serial.print('\n');
// if (rssi > best) {
// best = rssi;
// }//endif
// }//endfor
delay(15000);

[TheUruguayo]

After a while I manage to do it:
class myServerCallback : public BLEServerCallbacks {//get the address for example after conection happens

void onConnect(BLEServer* pServer, esp_ble_gatts_cb_param_t *param) {

memcpy(&peerAddress, param->connect.remote_bda, 6); //this way youll have the peerdevice addres

}
};
static void my_gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t* param) {
ESP_LOGW(LOG_TAG, "custom gap event handler, GAP event: %d", (uint8_t)event);

Serial.print("RSSI from gap event"); //be carefull with the speed you ask for the rssi if you have problems
rssi2=param->read_rssi_cmpl.rssi;
Serial.println(rssi2);

}

[Ranajayy]

hi, i tried using this but im getting an error that peerAddress was not declared in this scope, i need to do the same thing, get the rssi of the client connected to my esp, can you please help me on this im new to the ble concept

[hoangducnghi2207]

After a while I manage to do it: class myServerCallback : public BLEServerCallbacks {//get the address for example after conection happens

void onConnect(BLEServer* pServer, esp_ble_gatts_cb_param_t *param) {

memcpy(&peerAddress, param->connect.remote_bda, 6); //this way youll have the peerdevice addres

} }; static void my_gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t* param) { ESP_LOGW(LOG_TAG, "custom gap event handler, GAP event: %d", (uint8_t)event);

Serial.print("RSSI from gap event"); //be carefull with the speed you ask for the rssi if you have problems rssi2=param->read_rssi_cmpl.rssi; Serial.println(rssi2);

}

I also got the same error like KanaJayy, What should i do to solve this problem ?

[Hoffa25]

@hoangducnghi2207 did you get it to work?

[TheUruguayo]

I dont remember anything about what I did here, it was too long ago. I'll give you the link to the full project so you can check it out. https://github.com/TheUruguayo/BLE-ESP32-tracking-robot
I made a robot that tracks you using BLE.
Hope it helps

[TheUruguayo]

I will unsubscribe to this so I will not get further emails about it. If anyone has issues that have no answer my recomendation is to read the documentation.