NodeMCU32_WebRGBLED.ino
/*
* This sketch run on ESP32 with Arduino core for ESP32,
* demonstrates how to set up a simple HTTP-like server.
* The server will set a GPIO pins depending on the request,
* to control the brightness of RGB LED connected to:
* 23 : BLUE
* 22 : GREEN
* 21 : RED
*
* http://server_ip/rgb/rrggbb/
* where rr is the value set RED
* where gg is the value set GREEN
* where bb is the value set BLUE
* then terminate with '/'
* server_ip is the IP address of the ESP32, will be
* printed to Serial when the module is connected.
*/
#include <WiFi.h>
const char* ssid = "ssid";
const char* password = "password";
WiFiServer server(80);
#define MAX_LED_VALUE 99
// use first 3 channels of 16 channels (started from zero)
#define LEDC_CHANNEL_0_R 0
#define LEDC_CHANNEL_1_G 1
#define LEDC_CHANNEL_2_B 2
// use 13 bit precission for LEDC timer
#define LEDC_TIMER_13_BIT 13
// use 5000 Hz as a LEDC base frequency
#define LEDC_BASE_FREQ 5000
// LED PINs
#define LED_PIN_R 21
#define LED_PIN_G 22
#define LED_PIN_B 23
/*
Because Multiple libraries were found for "WiFi.h",
Arduino IDE will:
Used: ...\Arduino\hardware\espressif\esp32\libraries\WiFi
Not used: C:\Program Files (x86)\Arduino\libraries\WiFi
And exit with error:
'min' was not declared in this scope
So I have to program my own min()
*/
uint32_t min(uint32_t num1, uint32_t num2){
if(num1 < num2){
return num1;
}else{
return num2;
}
}
// Arduino like analogWrite
// value has to be between 0 and valueMax
void ledcAnalogWrite(uint8_t channel, uint32_t value, uint32_t valueMax = MAX_LED_VALUE) {
// calculate duty
uint32_t duty = (LEDC_BASE_FREQ / valueMax) * min(value, valueMax);
// write duty to LEDC
ledcWrite(channel, duty);
}
void setup() {
Serial.begin(115200);
delay(10);
// Setup timer and attach timer to a led pins
ledcSetup(LEDC_CHANNEL_0_R, LEDC_BASE_FREQ, LEDC_TIMER_13_BIT);
ledcAttachPin(LED_PIN_R, LEDC_CHANNEL_0_R);
ledcSetup(LEDC_CHANNEL_1_G, LEDC_BASE_FREQ, LEDC_TIMER_13_BIT);
ledcAttachPin(LED_PIN_G, LEDC_CHANNEL_1_G);
ledcSetup(LEDC_CHANNEL_2_B, LEDC_BASE_FREQ, LEDC_TIMER_13_BIT);
ledcAttachPin(LED_PIN_B, LEDC_CHANNEL_2_B);
// Connect to WiFi network
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
// Start the server
server.begin();
Serial.println("Server started");
// Print the IP address
Serial.println(WiFi.localIP());
}
void loop() {
// Check if a client has connected
WiFiClient client = server.available();
if (!client) {
return;
}
// Wait until the client sends some data
Serial.println("new client");
while(!client.available()){
delay(1);
}
// Read the first line of the request
String req = client.readStringUntil('\r');
Serial.println(req);
client.flush();
// Match the request
int valR, valG, valB;
String subStringR, subStringG, subStringB;
int index = req.indexOf("/rgb/");
if(index != -1){
if(req.charAt(index+11)=='/'){
subStringR = req.substring(index+5, index+7);
subStringG = req.substring(index+7, index+9);
subStringB = req.substring(index+9, index+11);
Serial.println("R: " + subStringR);
Serial.println("G: " + subStringG);
Serial.println("B: " + subStringB);
valR = subStringR.toInt();
valG = subStringG.toInt();
valB = subStringB.toInt();
Serial.println("valR: " + String(valR));
Serial.println("valG: " + String(valG));
Serial.println("valB: " + String(valB));
}
else{
Serial.println("Not terminated with /");
client.stop();
return;
}
}
else {
Serial.println("No /rgb/ found");
client.stop();
return;
}
// Set GPIOs according to the request
// No check valid of the requested setting
ledcAnalogWrite(LEDC_CHANNEL_0_R, valR);
ledcAnalogWrite(LEDC_CHANNEL_1_G, valG);
ledcAnalogWrite(LEDC_CHANNEL_2_B, valB);
client.flush();
// Prepare the response
String s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n<!DOCTYPE HTML>\r\n<html>\r\nGPIOs of RGB is now ";
s += String(valR) +":" + String(valG) + ":" + String(valB);
s += "</html>\n";
// Send the response to the client
client.print(s);
delay(1);
Serial.println("Client disonnected");
// The client will actually be disconnected
// when the function returns and 'client' object is detroyed
}
Connection:
