ESP32 using BLE and WiFi API calls gives error code -1 - c++

Question

I have a program trying to connect to a Bluetooth device and then sending an ack over a server (the server is private so I just used some pseudonym).
The first ACK on setup, goes through with 204 http return code which is fine, then it searches for a device, and whether it finds one or not it gives an error code of -1, then further on it gives 204 as well.
Here is the code that I have: (I have another project so this is just stripped down version trying things). This is also largely based form the Bluetooth client connect example on the esp32.
Code:
#include "BLEDevice.h"
#include "esp_bt.h"
#include "WiFi.h"
#include <HTTPClient.h>
#include <ArduinoJson.h>
#include <Arduino_JSON.h>
//WiFi variables
//HTTPClient http;
const char* ssid = "SSID";
const char* password = "Password";
char* serverName = "ServerName";
char* serverQR = "ServerName1";
String serverPath;
String httpRequestData;
bool wifiOn = 0;
bool wifiAck = 0;
int Connection = 0;
int httpResponseCode;
String Data = "";
String externalID = "";
bool answer = "false";
String payload = "{}";
BLEScan* pBLEScan;
// The remote service we wish to connect to.
static BLEUUID serviceUUID("0000fff0-0000-1000-8000-00805f9b34fb");
// The characteristic of the remote service we are interested in.
static BLEUUID charUUID("0000fff1-0000-1000-8000-00805f9b34fb");
static boolean doConnect = false; //should esp connect to ble device
static boolean connected = false; // is esp connected to a ble device
static boolean doScan = false; //should esp scan for ble devices
static BLERemoteCharacteristic* pRemoteCharacteristic; //init remote characterestic
static BLEAdvertisedDevice* myDevice; //init device found
static void notifyCallback( //beginning of functions, parameters follow
BLERemoteCharacteristic* pBLERemoteCharacteristic, //this is the device characterisitc value
uint8_t* pData, //data it received
size_t length,//length of data received
bool isNotify) {
Serial.print("Notify callback for characteristic ");
Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
Serial.print(" of data length ");
Serial.println(length);
Serial.print("data: ");
Serial.println((char*)pData);
esp_bt_controller_deinit();
esp_bt_controller_disable();
}
class MyClientCallback : public BLEClientCallbacks {
void onConnect(BLEClient* pclient) {//when connecting
connected = true;
Serial.println("onConnect");
}
void onDisconnect(BLEClient* pclient) {//when disconnecting
connected = false;
Serial.println("onDisconnect");
}
};
bool connectToServer() {//connect to ble device
Serial.print("Forming a connection to ");
Serial.println(myDevice->getAddress().toString().c_str());
BLEClient* pClient = BLEDevice::createClient();//create esp as a client
Serial.println(" - Created client");
pClient->setClientCallbacks(new MyClientCallback());//set the function of client callbacks
// Connect to the remove BLE server.
pClient->connect(myDevice); // if you pass BLEAdvertisedDevice instead of address, it will be
recognized type of peer device address (public or private)
Serial.println(" - Connected to server");
// Obtain a reference to the service we are after in the remote BLE server.
BLERemoteService* pRemoteService = pClient->getService(serviceUUID);//can we connect to ble device
if (pRemoteService == nullptr) {
Serial.print("Failed to find our service UUID: ");
Serial.println(serviceUUID.toString().c_str());
pClient->disconnect();
return false;
}
Serial.println(" - Found our service");
// Obtain a reference to the characteristic in the service of the remote BLE server.
pRemoteCharacteristic = pRemoteService->getCharacteristic(charUUID);//does the ble device have the
characteristic function we want?
if (pRemoteCharacteristic == nullptr) {
Serial.print("Failed to find our characteristic UUID: ");
Serial.println(charUUID.toString().c_str());
pClient->disconnect();
return false;
}
Serial.println(" - Found our characteristic");
// Read the value of the characteristic.
if (pRemoteCharacteristic->canRead()) {
std::string value = pRemoteCharacteristic->readValue();
Serial.print("The characteristic value was: ");
Serial.println(value.c_str());
}
if (pRemoteCharacteristic->canNotify()) //if ble server transmits data do a callback
pRemoteCharacteristic->registerForNotify(notifyCallback);
connected = true;
return true;
}
/**
Scan for BLE servers and find the first one that advertises the service we are looking for.
*/
class MyAdvertisedDeviceCallbacks: public BLEAdvertisedDeviceCallbacks {//When a scan is activated
/**
Called for each advertising BLE server.
*/
void onResult(BLEAdvertisedDevice advertisedDevice) {//when a ble device is found
Serial.print("BLE Advertised Device found: ");
Serial.println(advertisedDevice.toString().c_str());
// We have found a device, let us now see if it contains the service we are looking for.
if (advertisedDevice.haveServiceUUID() && advertisedDevice.isAdvertisingService(serviceUUID)) {
BLEDevice::getScan()->stop();
myDevice = new BLEAdvertisedDevice(advertisedDevice);//ble server connected
doConnect = true;//has to connect
doScan = true;//has to scan
} // Found our server
} // onResult
}; // MyAdvertisedDeviceCallbacks
void setup() {
Serial.begin(115200);
Serial.println("Starting Arduino BLE Client application...");
BLEDevice::init("");
// Retrieve a Scanner and set the callback we want to use to be informed when we
// have detected a new device. Specify that we want active scanning and start the
// scan to run for 5 seconds.
pBLEScan = BLEDevice::getScan();
pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
pBLEScan->setActiveScan(true);
//WiFi setup
Serial.println();
Serial.printf("Connecting to %s\n", ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED)
{
Serial.println("Connecting to WiFi...");
delay(1000);
}//end while
Serial.print("Connected, IP address: ");
Serial.println(WiFi.localIP());
HTTPClient http;
serverPath = serverName;
if (WiFi.status() == WL_CONNECTED) {
// Your Domain name with URL path or IP address with path
http.begin(serverPath.c_str());
// Data to send with HTTP POST
JSONVar json_test;
json_test["id"] = WiFi.macAddress();
httpRequestData = JSON.stringify(json_test);
// If you need an HTTP request with a content type: application/json, use the following:
http.addHeader("Content-Type", "application/json");
httpResponseCode = http.POST(httpRequestData);
payload = " {}";
if (httpResponseCode > 0) {
Serial.print("HTTP Response code: ");
Serial.println(httpResponseCode);
Serial.println("This is the response code");
}
else {
Serial.print("Error code: ");
Serial.println(httpResponseCode);
}
// Free resources
http.end();
WiFi.disconnect(true);
delay(1); // disable WIFI altogether
WiFi.mode(WIFI_OFF);
delay(1);
} else
{
Serial.println("WiFi disconnected");
}
} // End of setup.
// This is the Arduino main loop function.
void loop() {
esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
esp_bt_controller_init(&bt_cfg);
esp_bt_controller_enable(ESP_BT_MODE_BLE);
if (!connected)
{
Serial.println("Initialising");
pBLEScan = BLEDevice::getScan();
pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
pBLEScan->setActiveScan(true);
Serial.println("Scan starting");
pBLEScan->start(30, false);
Serial.println("Scan ended");
}
// If the flag "doConnect" is true then we have scanned for and found the desired
// BLE Server with which we wish to connect. Now we connect to it. Once we are
// connected we set the connected flag to be true.
if (doConnect == true) {//if ble server was found connect to it
if (connectToServer()) {
Serial.println("We are now connected to the BLE Server.");
} else {
Serial.println("We have failed to connect to the server; there is nothin more we will do.");
}
doConnect = false;
}
esp_bt_controller_deinit();
esp_bt_controller_disable();
//WiFi setup
Serial.println();
Serial.printf("Connecting to %s\n", ssid);
WiFi.begin(ssid, password);
//WiFi.config(staticIP, gateway, subnet);
while (WiFi.status() != WL_CONNECTED)
{
Serial.println("Connecting to WiFi...");
delay(1000);
}//end while
Serial.print("Connected, IP address: ");
Serial.println(WiFi.localIP());
HTTPClient http;
serverPath = serverName;
if (WiFi.status() == WL_CONNECTED) {
// Your Domain name with URL path or IP address with path
http.begin(serverPath.c_str());
// Data to send with HTTP POST
JSONVar json_test;
json_test["id"] = WiFi.macAddress();
httpRequestData = JSON.stringify(json_test);
// If you need an HTTP request with a content type: application/json, use the following:
http.addHeader("Content-Type", "application/json");
httpResponseCode = http.POST(httpRequestData);
if (httpResponseCode > 0) {
Serial.print("HTTP Response code: ");
Serial.println(httpResponseCode);
Serial.println("This is the loop");
}
else {
Serial.print("Error code: ");
Serial.println(httpResponseCode);
Serial.println("This is the loop");
}
// Free resources
http.end();
WiFi.disconnect(true);
delay(1); // disable WIFI altogether
WiFi.mode(WIFI_OFF);
delay(1);
} else
{
Serial.println("WiFi disconnected");
}
delay(1000); // Delay a second between loops.
} // End of loop
The output of the code is:
Starting Arduino BLE Client application...
Connecting to SSID Connecting to WiFi... Connected, IP address: IP HTTP Response code: 204 This is the response code IS this done? Initialising Scan starting BLE Advertised Device found: Name: , Address: address, manufacturer data:random stuff Scan ended Forming a connection to addresss
- Created client onConnect
- Connected to server
- Found our service
- Found our characteristic We are now connected to the BLE Server.
Connecting to SSID Connecting to WiFi... Connected, IP address: IP Error code: -1 This is the loop
Connecting to SSID Connecting to WiFi... Connected, IP address: IP HTTP Response code: 204 This is the loop
Connecting to SSID Connecting to WiFi... Connected, IP address: IP HTTP Response code: 204 This is the loop
My question basically is does anyone know what an erro0 rcode if -1 is? On my main project I am unable to send a get request after scanning for a ble device even if I disabl the controller.

Answer 1

To answer your question about error code -1:
It means that a connection was not successful according to this example from the HTTPClient repository.
Your log shows that you are able to connect to your server and afterwards to your BLE peripheral. But it seems like you never disconnect from the peripheral and continue to block the other wifi connections. Have a look at this for further ideas on using BLE and WiFi together.