I am working with Arduino Nano BLE and my device has Microchip RN4871 BLE module. When I use the code below, arduino retrieves its attributes faster and each time it connects to my device.
#include <ArduinoBLE.h>
void setup() {
Serial.begin(9600);
while (!Serial);
// begin initialization
if (!BLE.begin()) {
Serial.println("starting BLE failed!");
while (1);
}
Serial.println("BLE Central - Peripheral Explorer");
}
void loop() {
// start scanning for peripherals
BLE.scan();
// check if a peripheral has been discovered
BLEDevice peripheral = BLE.available();
if (peripheral) {
// discovered a peripheral, print out address, local name, and advertised service
Serial.print("Found ");
Serial.print(peripheral.address());
Serial.print(" '");
Serial.print(peripheral.localName());
Serial.print("' ");
Serial.print(peripheral.advertisedServiceUuid());
Serial.println();
if (peripheral.localName().substring(0,3) == "AP-") {
Serial.print("String Found \t \t");
// stop scanning
BLE.stopScan();
explorerPeripheral(peripheral);
}
}
}
void explorerPeripheral(BLEDevice peripheral) {
// connect to the peripheral
Serial.println("Connecting ...");
if (peripheral.connect()) {
Serial.println("Connected");
} else {
Serial.println("Failed to connect!");
return;
}
// discover peripheral attributes
Serial.println("Discovering attributes ...");
if (peripheral.discoverAttributes()) {
Serial.println("Attributes discovered");
} else {
Serial.println("Attribute discovery failed!");
peripheral.disconnect();
return;
}
// read and print device name of peripheral
Serial.println();
Serial.print("Device name: ");
Serial.println(peripheral.deviceName());
Serial.print("Appearance: 0x");
Serial.println(peripheral.appearance(), HEX);
Serial.println();
// loop the services of the peripheral and explore each
for (int i = 0; i < peripheral.serviceCount(); i++) {
BLEService service = peripheral.service(i);
exploreService(service);
}
Serial.println();
// we are done exploring, disconnect
Serial.println("Disconnecting ...");
peripheral.disconnect();
Serial.println("Disconnected");
}
void exploreService(BLEService service) {
// print the UUID of the service
Serial.print("Service ");
Serial.println(service.uuid());
// loop the characteristics of the service and explore each
for (int i = 0; i < service.characteristicCount(); i++) {
BLECharacteristic characteristic = service.characteristic(i);
exploreCharacteristic(characteristic);
}
}
void exploreCharacteristic(BLECharacteristic characteristic) {
// print the UUID and properties of the characteristic
Serial.print("\tCharacteristic ");
Serial.print(characteristic.uuid());
Serial.print(", properties 0x");
Serial.print(characteristic.properties(), HEX);
// check if the characteristic is readable
if (characteristic.canRead()) {
// read the characteristic value
characteristic.read();
if (characteristic.valueLength() > 0) {
// print out the value of the characteristic
Serial.print(", value 0x");
printData(characteristic.value(), characteristic.valueLength());
}
}
Serial.println();
// loop the descriptors of the characteristic and explore each
for (int i = 0; i < characteristic.descriptorCount(); i++) {
BLEDescriptor descriptor = characteristic.descriptor(i);
exploreDescriptor(descriptor);
}
}
void exploreDescriptor(BLEDescriptor descriptor) {
// print the UUID of the descriptor
Serial.print("\t\tDescriptor ");
Serial.print(descriptor.uuid());
// read the descriptor value
descriptor.read();
// print out the value of the descriptor
Serial.print(", value 0x");
printData(descriptor.value(), descriptor.valueLength());
Serial.println();
}
void printData(const unsigned char data[], int length) {
for (int i = 0; i < length; i++) {
unsigned char b = data[i];
if (b < 16) {
Serial.print("0");
}
Serial.print(b, HEX);
}
}
But when I try to connect to my device in same fashion to write to my microchip module, it often fails to connect or if it sends data then my devices doesn't acts on it thinking it is some junk data. Most of the time, with the code below, it fails to even scan my device.
#include <ArduinoBLE.h>
void setup() {
Serial.begin(9600);
while (!Serial);
// begin initialization
BLE.begin();
Serial.println("Trying to connect to Microchip UUID");
Serial.println();
}
void loop() {
// start scanning for peripherals
BLE.scan();
// check if a peripheral has been discovered
Serial.println("Scanning");
BLEDevice peripheral = BLE.available();
if (peripheral) {
Serial.print("Detected ");
Serial.print(peripheral.address());
Serial.print(" '");
Serial.print(peripheral.localName());
Serial.print("' ");
Serial.print(peripheral.advertisedServiceUuid());
Serial.println();
if (peripheral.localName().substring(0,3) == "AP-") {
// stop scanning
BLE.stopScan();
controlLed(peripheral);
Serial.println("RESTART");
}
}
delay(5000);
}
//----------------------------------------------------------------------------
void controlLed(BLEDevice peripheral) {
if (peripheral.connect()) {
Serial.println("Connected to receiver");
} else {
Serial.println("Failed!");
return;
}
Serial.println("Discovering devices ...");
if (peripheral.discoverAttributes()) {
Serial.println("devices discovered");
} else {
Serial.println("device discovery failed!");
peripheral.disconnect();
return;
}
BLECharacteristic ledCharacteristic = peripheral.characteristic("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx");
if (!ledCharacteristic) {
Serial.println("No characteristic");
peripheral.disconnect();
return;
} else if (!ledCharacteristic.canWrite()) {
Serial.println("Can't write");
peripheral.disconnect();
return;
}
Serial.print("peripheral connected? \t");
Serial.println(peripheral.connected());
if (peripheral.connected()) {
char arr[6] = "b440\r";
char arr1[6] = "b0\r";
Serial.println("transmitting data");
// Serial.println(arr);
for(int i=0; i<5; i++){
ledCharacteristic.writeValue((byte)arr[i]);
Serial.println(arr[i]);
}
delay(3000);
for(int i=0; i<5; i++){
ledCharacteristic.writeValue((byte)arr1[i]);
Serial.println(arr1[i]);
}
}
Serial.println("Peripheral disconnected");
}
Can someone tell me what am I doing wrong here? Also, I want if I want to send hex data after some ASCII chars how do I do that? So far, I have tried 0xdd but that didn't work.