Hardware Connection

As shown in the diagram, connect the red, green, and blue pins of the RGB-LED module to the Arduino pins 1, 2, and 3 on the development board. The RGB-LED used here is a common cathode LED, with the common pin connected to GND. If using a common anode LED, it should be connected to 3.3V.

RGB-LED Module Schematic：https://oshwhub.com/jinleili/rgb-led-module

Code Analysis

 #include "BLEDevice.h"

 

 // Choose the RGB LED type

 // #define AnodeRGB

 #define CathodeRGB

 

 // Choose 3 PWM pins for RGB LED pins refer to the pinmap of using board

 #define LED_RED 1

 #define LED_GRN 2

 #define LED_BLU 3

 

 #define UART_SERVICE_UUID      "6E400001-B5A3-F393-E0A9-E50E24DCCA9E"

 #define CHARACTERISTIC_UUID_RX "6E400002-B5A3-F393-E0A9-E50E24DCCA9E"

 #define CHARACTERISTIC_UUID_TX "6E400003-B5A3-F393-E0A9-E50E24DCCA9E"

 

 #define STRING_BUF_SIZE 100

 

 BLEService UartService(UART_SERVICE_UUID);

 BLECharacteristic Rx(CHARACTERISTIC_UUID_RX);

 BLECharacteristic Tx(CHARACTERISTIC_UUID_TX);

 BLEAdvertData advdata;

 BLEAdvertData scndata;

 bool notify = false;

 

 void readCB(BLECharacteristic* chr, uint8_t connID)

 {

     printf("Characteristic %s read by connection %d \n", chr->getUUID().str(), connID);

 }

 

 void writeCB(BLECharacteristic* chr, uint8_t connID)

 {

     printf("Characteristic %s write by connection %d :\n", chr->getUUID().str(), connID);

     uint16_t datalen = chr->getDataLen();

     if (datalen > 0) {

         if (chr->readData8() == '!') {

             uint8_t command[datalen];

             chr->getData(command, datalen);

             if (command[1] == 'C') {

                 // print hex

                 printf("Color command R = %x G = %x B = %x \n", command[2], command[3], command[4]);

                 // print decimal

                 // printf("Color command R = %d G = %d B = %d \n", command[2], command[3], command[4]);

 #if defined(CathodeRGB)

                 analogWrite(LED_RED, command[2]);

                 analogWrite(LED_GRN, command[3]);

                 analogWrite(LED_BLU, command[4]);

 #elif defined(AnodeRGB)

                 analogWrite(LED_RED, (255 - command[2]));

                 analogWrite(LED_GRN, (255 - command[3]));

                 analogWrite(LED_BLU, (255 - command[4]));

 #else

                 printf("Error, please choose the RGB LED type \n");

 #endif

             }

         } else {

             Serial.print("Received string: ");

             Serial.print(chr->readString());

             Serial.println();

         }

     }

 }

 

 void notifCB(BLECharacteristic* chr, uint8_t connID, uint16_t cccd)

 {

     if (cccd & GATT_CLIENT_CHAR_CONFIG_NOTIFY) {

         printf("Notifications enabled on Characteristic %s for connection %d \n", chr->getUUID().str(), connID);

         notify...