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ESP32-CAM to Switch both

Setup ESP-32 CAM Programming Environment

Ref. ESP32-CAM_JP

Additional Boards manager URLs:

https://dl.espressif.com/dl/package_esp32_index.json

Boards Manager

ESP32

Setting

Connection

USB-Serial ESP32-CAM
RX U0T (UART 0 TX)
TX U0R (UART 0 RX)
VCC 5V
GND GND
IO0 to GND (When Programming)

Note

Select Bootloader Mode
GPIO0
The ESP32 will enter the serial bootloader when GPIO0 is held low on reset. Otherwise it will run the program in flash.

GPIO0 Input Mode
Low/GND ROM serial bootloader for esptool
High/VCC Normal execution mode

GPIO0 has an internal pullup resistor, so if it is left unconnected then it will pull high.

Ref. Boot Mode Selection

Code

void setup()
{
  Serial.begin(9600); // 通信速度
}


void loop()
{
  Serial.println("Hello, World"); // Hello, Worldを出力
  delay(1000); // 1秒待つ
}

Serial Monitor

  • IO0 disconnect to GND(connect to internal Pull-up to execution mode)
  • Push rest button on ESP32-CAM

Switch bot

Ref. ESP32 Swich bot_JP

Code

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//アクセスするときはURLパラメーターの最後に&をつけること!

#include <WiFi.h>

// 使用するWi-Fiとそのパスワードに書き換えてください
const char* ssid     = "fablabkannai";
const char* password = "marumie";

// ポート80番を使用
WiFiServer server(80);

// HTTPリクエストを格納する変数
String header;

// 値の設定に使用する変数
String valueString = String(5);
String delay_valueString = String(500);
int pos1 = 0;
int pos2 = 0;

//pin
const int servo_pin = 16;

//サーボモーターの回転角
const int servo_left   = 26;
const int servo_center = 75;
const int servo_right  = 123;


void setup() {
  pinMode(4, OUTPUT);

  //ledc setting
  ledcSetup(0, 50, 10);  // 0ch 50 Hz 10bit resolution
  ledcAttachPin(servo_pin, 0); // 15pin, 0ch

  //シリアル通信開始
  Serial.begin(115200);

  //起動時にフラッシュライトを点滅させる
  for(int i=0; i<5; i=i+1) {
    digitalWrite(4, HIGH);
    delay(50);
    digitalWrite(4, LOW);
    delay(50);
  }

  // Wi-Fiに接続
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  // ローカルIPを表示(このIPにスマホなどからアクセスします)
  Serial.println("");
  Serial.println("WiFi connected.");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
  server.begin();
}

void loop(){
  WiFiClient client = server.available();   // Listen for incoming clients

  if (client) {                             // If a new client connects,
    Serial.println("New Client.");          // print a message out in the serial port
    String currentLine = "";                // make a String to hold incoming data from the client
    while (client.connected()) {            // loop while the client's connected
      if (client.available()) {             // if there's bytes to read from the client,
        char c = client.read();             // read a byte, then
        Serial.write(c);                    // print it out the serial monitor
        header += c;
        if (c == '\n') {                    // if the byte is a newline character
          // if the current line is blank, you got two newline characters in a row.
          // that's the end of the client HTTP request, so send a response:
          if (currentLine.length() == 0) {
            // HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
            // and a content-type so the client knows what's coming, then a blank line:
            client.println("HTTP/1.1 200 OK");
            client.println("Content-type:text/html");
            client.println("Connection: close");
            client.println();


            // Display the HTML web page
            client.println("<!DOCTYPE html><html>");
            client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\" http-equiv=\"content-type\" charset=\"utf-8\"><title>ESP32 servo controller</title>");

            // CSS to style the on/off buttons
            // Feel free to change the background-color and font-size attributes to fit your preferences
            client.println("<style>.block{display: inline-block; vertical-align: middle; height: 50px; font-size: 0;}");
            client.println(".btn-square-shadow {display: inline-block; width: 300px; height: 50px; text-decoration: none; background: #668ad8; color: #FFF; border-bottom: solid 4px #627295; border-radius: 3px; font-size: 30px;}");
            client.println(".btn-square-shadow:active {-webkit-transform: translateY(4px); transform: translateY(4px);  box-shadow: 0px 0px 1px rgba(0, 0, 0, 0.2);  border-bottom: none;}");
            client.println("</style>");
            client.println("<script src=\"https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js\"></script>");

            // Web Page
            client.println("</head><body style='text-align: center;'><h1>ESP32 サーボモーター コントロールパネル</h1>");
            //servo slide bar <--------------------------------------------------------------------------------------------------------------------------------------------------------------------ESP32's IP address. To find open serial monitor with 115200bps
            client.println("<div class='left block'> <a href='http://192.168.2.111/?angle=50&delay=500&'><button id='entrance_button' class='btn-square-shadow' type='button'>玄関の電気</button></a></div>");          
            client.println("<div class='right block'><a href='http://192.168.2.111/?angle=100&delay=500&'><button id='room_button' class='btn-square-shadow' type='button'>部屋の電気</button></a></div>");
            client.println("</body></html>");     


            //HTTPリクエストの処理部分
            delay_valueString = "500";
            pos1 = header.indexOf('=',18);
            pos2 = header.indexOf('&',18);
            if(pos1!=-1 && pos2!=-1) {
              delay_valueString = header.substring(pos1+1, pos2);
              Serial.print("pos:");
              Serial.println(pos1);
              Serial.println(pos2);

            } else {
              Serial.print("defaultサーボ待機時間:");
              Serial.println(delay_valueString.toInt());
            }
            Serial.print("サーボ待機時間:");
            Serial.println(delay_valueString.toInt());


            pos1 = header.indexOf('=');
            pos2 = header.indexOf('&');
            valueString = header.substring(pos1+1, pos2);
            Serial.print("URLパラメーター:");
            Serial.println(valueString);


            if(valueString.toInt()>=26 && valueString.toInt()<=123) {

              //サーボモーターを回転
              digitalWrite(4, HIGH);
              delay(50);
              digitalWrite(4, LOW);


              ledcWrite(0, servo_center);
              delay(delay_valueString.toInt());
              ledcWrite(0, valueString.toInt());
              delay(delay_valueString.toInt());
              ledcWrite(0, servo_center);
              // バグ防止
              delay(delay_valueString.toInt());
              ledcWrite(0, 0);

              digitalWrite(4, HIGH);
              delay(50);
              digitalWrite(4, LOW);


            } else {
              Serial.println("URLパラメーター エラー!");
            }


            // HTTPレスポンスの終了
            client.println();
            // Break out of the while loop
            break;
          } else {
            currentLine = "";
          }
        } else if (c != '\r') {
          currentLine += c;
        }
      }
    }
    // Clear the header variable
    header = "";
    // 接続を切断
    client.stop();
    Serial.println("Client disconnected.");
    Serial.println("");
  }
}

Connection

ESP32-CAM
5V 5V (Power+)
GND GND(Power-)
3V3 Servo VCC
IO16 Servo signal
GND Servo GND

How to use

Find IP address

  • Open Serial monitor and Find IP address

Replace the IP address in this part of the code

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client.println("<div class='left block'> <a href='http://192.168.2.111/?angle=50&delay=500&'><button id='entrance_button' class='btn-square-shadow' type='button'>玄関の電気</button></a></div>");          
client.println("<div class='right block'><a href='http://192.168.2.111/?angle=100&delay=500&'><button id='room_button' class='btn-square-shadow' type='button'>部屋の電気</button></a></div>");

Direct switch

Access from browser

http://192.168.2.111/?angle=50&delay=500&
  • 192.168.2.111: loacal IP address of ESP32-CAM in Arduio Sketch
  • angle : servo rotate degree (23-123)
  • delay: set delay when servo move back

Switches on screen

Open in browser

http://192.168.2.111


Last update: May 3, 2022