i2c esp8266: how to, rete 5V, 3.3V, velocità e pin personalizzati

	  Wire.pins(D2, D1);               // Pin predefiniti, puoi rimuoverlo

	  Wire.begin(0x12);                // unisciti al bus i2c con indirizzo 0x12
	  Wire.setClockStretchLimit(1500);
	  Wire.setClock(10000L);           // Max 50kHz

Scanning... 
Errore sconosciuto all'indirizzo 0x12
fatto

Scanning...
Trovato dispositivo I2C all'indirizzo 0x25  !
Trovato dispositivo I2C all'indirizzo 0x60  !
Trovato dispositivo I2C all'indirizzo 0x6B  ! 
fatto

	Wire.begin();          // join i2c bus (address optional for master)
	Wire.setClock(40000L); // Set speed at 40kHz

	Wire.beginTransmission(0x12); 	// Avvia canale con slave 0x12
	Wire.write(GET_NAME);        	// invia dati allo slave
	Wire.endTransmission();       	// Termina la trasmissione

	Wire.onReceive(receiveEvent);    // registra un gestore di eventi per i dati ricevuti

// funzione che si esegue ogni volta che i dati vengono ricevuti dal master
// questa funzione è registrata come un evento, vedere setup()
void receiveEvent(int numBytes) {
	if (numBytes==1){
		int requestVal = Wire.read();

		Serial.print(F("Richiesta ricevuta -> "));
		Serial.println(requestVal);
		request = static_cast<REQUEST_TYPE>(requestVal);
	}else{
		Serial.print(F("Nessun parametro ricevuto!"));
	}
}

	Wire.requestFrom(0x08, 14);    // richiede 14 byte dal dispositivo slave 0x08

// function that executes whenever data is requested by master
// this function is registered as an event, see setup()
void requestEvent() {
	switch (request) {
		case NONE:
			Serial.println(F("Not good, no request type!"));
			break;
		case GET_NAME:
			Wire.write("esp8266       "); // send 14 bytes to master
			request = NONE;
			break;
		case GET_AGE:
			Wire.write((byte)45); // send 1 bytes to master
			request = NONE;
			break;
		default:
			break;
	}
}

/**
 * i2c network: send parameter to client and receive response
 * with data relative to the request
 *
 * by Renzo Mischianti <www.mischianti.org>
 *
 * https://mischianti.org
 *
 * esp8266 	<------> 	esp8266
 * GND					GND
 * D1					D1
 * D2					D2
 *
 */

#include <Wire.h>

enum REQUEST_TYPE {
	NONE = -1,
	GET_NAME = 0,
	GET_AGE
};

void setup() {
	Wire.begin();          // join i2c bus (address optional for master)
	Wire.setClock(40000L); // Set speed at 40kHz

	Serial.begin(9600);  // start serial for output

	while (!Serial){}

	Serial.println();
	Serial.println(F("Starting request!"));


	Wire.beginTransmission(0x12); 	// Start channel with slave 0x12
	Wire.write(GET_NAME);        		// send data to the slave
	Wire.endTransmission();       	// End transmission

	delay(1000); // added to get better Serial print

	Wire.requestFrom(0x12, 14);    // request 14 bytes from slave device 0x12

	while (Wire.available()) { // slave may send less than requested
	      char c = Wire.read(); // receive a byte as character
	      Serial.print(c);         // print the character
	}

	Serial.println();

	delay(1000); // added to get better Serial print

	Wire.beginTransmission(0x12); 	// Start channel with slave 0x12
	Wire.write(GET_AGE);        		// send data to the slave
	Wire.endTransmission();       	// End transmission

	delay(1000); // added to get better Serial print

	Wire.requestFrom(0x12, 1);    // request 1 bytes from slave device 0x12

	while (Wire.available()) { // slave may send less than requested
		int c = (int)Wire.read(); // receive a byte as character
		Serial.println(c);         // print the character
	}
	delay(1000); // added to get better Serial print

	Serial.println();

}

void loop() {
}

/**
 * i2c network: send parameter to client and receive response
 * with data relative to the request. SLAVE SKETCH
 *
 * by Renzo Mischianti <www.mischianti.org>
 *
 * https://mischianti.org
 *
 * esp8266 	<------> 	esp8266
 * GND					GND
 * D1					D1
 * D2					D2
 *
 */

#include <Wire.h>

enum REQUEST_TYPE {
	NONE = -1,
	GET_NAME = 0,
	GET_AGE
};

void requestEvent();
void receiveEvent(int numBytes);

REQUEST_TYPE request = NONE;

void setup() {
//	  Wire.pins(D2, D1);

	  Wire.begin(0x12);                // join i2c bus with address 0x12
//	  Wire.setClockStretchLimit(1500);
//	  Wire.setClock(50000L);

	Serial.begin(9600);  // start serial for output

	while (!Serial){}

	Serial.println(F("Starting!!"));

	// event handler initializations
	Wire.onReceive(receiveEvent);    // register an event handler for received data
	Wire.onRequest(requestEvent);   // register an event handler for data requests
}

void loop() {
//  delay(100);
}

// function that executes whenever data is requested by master
// this function is registered as an event, see setup()
void requestEvent() {
	switch (request) {
		case NONE:
			Serial.println(F("Not good, no request type!"));
			break;
		case GET_NAME:
			Wire.write("esp8266       "); // send 14 bytes to master
			request = NONE;
			break;
		case GET_AGE:
			Wire.write((byte)45); // send 1 bytes to master
			request = NONE;
			break;
		default:
			break;
	}
}

// function that executes whenever data is received by master
// this function is registered as an event, see setup()
void receiveEvent(int numBytes) {
	if (numBytes==1){
		int requestVal = Wire.read();

		Serial.print(F("Received request -> "));
		Serial.println(requestVal);
		request = static_cast<REQUEST_TYPE>(requestVal);
	}else{
		Serial.print(F("No parameter received!"));
	}
}

17:10:06: Starting request!
17:10:07: esp8266       
17:10:09: 45

17:10:06: Received request -> 0
17:10:08: Received request -> 1

#include <Wire.h>

void setup()
{
  Wire.begin();

  Serial.begin(9600);
  Serial.println("\nI2C Scanner");
}


void loop()
{
  byte error, address;
  int nDevices;

  Serial.println("Scanning...");

  nDevices = 0;
  for(address = 1; address < 127; address++ ) 
  {
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();

    if (error == 0)
    {
      Serial.print("I2C device found at address 0x");
      if (address<16) 
        Serial.print("0");
      Serial.print(address,HEX);
      Serial.println("  !");

      nDevices++;
    }
    else if (error==4) 
    {
      Serial.print("Unknow error at address 0x");
      if (address<16) 
        Serial.print("0");
      Serial.println(address,HEX);
    }    
  }
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");

  delay(5000);           // wait 5 seconds for next scan
}

	  Wire.begin(0x12);                // join i2c bus with address 0x12
// ------ If you have throuble uncomment these lines --------
// ------ and compile with processor speed at 160Mhz --------
	  Wire.setClockStretchLimit(1500);
	  Wire.setClock(40000L);
// ----------------------------------------------------------

/**
 * i2c network: send parameter to client and receive response
 * with data relative to the request
 *
 * by Renzo Mischianti <www.mischianti.org>
 *
 * https://mischianti.org
 *
 *
 * Arduino UNO <------> 	Logic converter <------> 	esp8266 Master <------> 	esp8266 Slave
 * GND						GND			GND				GND							GND
 * 5v						HV			LV				3.3v
 * A4						HV1			LV1				D1							D1
 * A5						HV2			LV2				D2							D2
 *
 */

#include <Wire.h>

enum REQUEST_TYPE {
	NONE = -1,
	GET_NAME = 0,
	GET_AGE
};

void setup() {
	Wire.begin();          // join i2c bus (address optional for master)
	Wire.setClock(40000L); // Set speed at 40kHz

	Serial.begin(9600);  // start serial for output

	while (!Serial){}

	Serial.println();
	Serial.println(F("Starting request!"));


	Wire.beginTransmission(0x08); 	// Start channel with slave 0x08
	Wire.write(GET_NAME);        		// send data to the slave
	Wire.endTransmission();       	// End transmission

	delay(1000); // added to get better Serial print

	Wire.requestFrom(0x08, 14);    // request 14 bytes from slave device 0x08

	while (Wire.available()) { // slave may send less than requested
	      char c = Wire.read(); // receive a byte as character
	      Serial.print(c);         // print the character
	}

	Serial.println();

	delay(1000); // added to get better Serial print
	Wire.beginTransmission(0x12); 	// Start channel with slave 0x12
	Wire.write(GET_NAME);        		// send data to the slave
	Wire.endTransmission();       	// End transmission

	delay(1000); // added to get better Serial print

	Wire.requestFrom(0x12, 14);    // request 14 bytes from slave device 0x12

	while (Wire.available()) { // slave may send less than requested
	      char c = Wire.read(); // receive a byte as character
	      Serial.print(c);         // print the character
	}

	Serial.println();

	delay(1000); // added to get better Serial print

	Wire.beginTransmission(0x08); 	// Start channel with slave 0x08
	Wire.write(GET_AGE);        		// send data to the slave
	Wire.endTransmission();       	// End transmission

	delay(1000); // added to get better Serial print

	Wire.requestFrom(0x08, 1);    // request 1 bytes from slave device 0x08

	while (Wire.available()) { // slave may send less than requested
		int c = (int)Wire.read(); // receive a byte as character
		Serial.println(c);         // print the character
	}
	delay(1000); // added to get better Serial print

	Serial.println();

	delay(1000); // added to get better Serial print

	Wire.beginTransmission(0x12); 	// Start channel with slave 0x12
	Wire.write(GET_AGE);        		// send data to the slave
	Wire.endTransmission();       	// End transmission

	delay(1000); // added to get better Serial print

	Wire.requestFrom(0x12, 1);    // request 1 bytes from slave device 0x12

	while (Wire.available()) { // slave may send less than requested
		int c = (int)Wire.read(); // receive a byte as character
		Serial.println(c);         // print the character
	}
	delay(1000); // added to get better Serial print

	Serial.println();

}

void loop() {
}

/**
 * i2c network: send parameter to client and receive response
 * with data relative to the request. SLAVE SKETCH
 *
 * by Renzo Mischianti <www.mischianti.org>
 *
 * https://mischianti.org
 *
 * Arduino UNO <------> 	Logic converter <------> 	esp8266 Master <------> 	esp8266 Slave
 * GND						GND			GND				GND							GND
 * 5v						HV			LV				3.3v
 * A4						HV1			LV1				D1							D1
 * A5						HV2			LV2				D2							D2
 *
 */

#include <Wire.h>

enum REQUEST_TYPE {
	NONE = -1,
	GET_NAME = 0,
	GET_AGE
};

void requestEvent();
void receiveEvent(int numBytes);

REQUEST_TYPE request = NONE;

void setup() {
	Wire.begin(0x08);                // join i2c bus with address #8

	  Serial.begin(9600);  // start serial for output

	while (!Serial){}

	// event handler initializations
	Wire.onReceive(receiveEvent);    // register an event handler for received data
	Wire.onRequest(requestEvent);   // register an event handler for data requests
}

void loop() {
//  delay(100);
}

// function that executes whenever data is requested by master
// this function is registered as an event, see setup()
void requestEvent() {
	switch (request) {
		case NONE:
			Serial.println(F("Not good, no request type!"));
			break;
		case GET_NAME:
			Wire.write("ArduinoUNO    "); // send 14 bytes to master
			request = NONE;
			break;
		case GET_AGE:
			Wire.write((byte)43); // send 1 bytes to master
			request = NONE;
			break;
		default:
			break;
	}
}

// function that executes whenever data is received by master
// this function is registered as an event, see setup()
void receiveEvent(int numBytes) {
	if (numBytes==1){
		int requestVal = Wire.read();

		Serial.print(F("Received request -> "));
		Serial.println(requestVal);
		request = static_cast<REQUEST_TYPE>(requestVal);
	}else{
		Serial.print(F("No parameter received!"));
	}
}

22:33:55: Scanning...
22:33:55: I2C device found at address 0x08  !
22:33:55: I2C device found at address 0x12  !
22:33:55: done

22:51:28: Starting request!
22:51:29: ArduinoUNO    
22:51:31: esp8266       
22:51:33: 43
22:51:36: 45

	  Wire.pins(D6, D5);

/**
 * i2c network: send parameter to client and receive response
 * with data relative to the request. SLAVE SKETCH
 *
 * by Renzo Mischianti <www.mischianti.org>
 *
 * https://mischianti.org
 *
 * esp8266 	<------> 	esp8266
 * GND					GND
 * D1					D5
 * D2					D6
 *
 */

#include <Wire.h>

enum REQUEST_TYPE {
	NONE = -1,
	GET_NAME = 0,
	GET_AGE
};

void requestEvent();
void receiveEvent(int numBytes);

REQUEST_TYPE request = NONE;

void setup() {
	  Wire.pins(D6, D5);

	  Wire.begin(0x12);                // join i2c bus with address 0x12
// ------ If you have throuble uncomment these lines --------
// ------ and compile with processor speed at 160Mhz --------
	  Wire.setClockStretchLimit(1500);
	  Wire.setClock(40000L);
// ----------------------------------------------------------

	Serial.begin(9600);  // start serial for output

	while (!Serial){}

	Serial.println(F("Starting!!"));

	// event handler initializations
	Wire.onReceive(receiveEvent);    // register an event handler for received data
	Wire.onRequest(requestEvent);   // register an event handler for data requests
}

void loop() {
//  delay(100);
}

// function that executes whenever data is requested by master
// this function is registered as an event, see setup()
void requestEvent() {
	switch (request) {
		case NONE:
			Serial.println(F("Not good, no request type!"));
			break;
		case GET_NAME:
			Wire.write("esp8266       "); // send 14 bytes to master
			request = NONE;
			break;
		case GET_AGE:
			Wire.write((byte)45); // send 1 bytes to master
			request = NONE;
			break;
		default:
			break;
	}
}

// function that executes whenever data is received by master
// this function is registered as an event, see setup()
void receiveEvent(int numBytes) {
	if (numBytes==1){
		int requestVal = Wire.read();

		Serial.print(F("Received request -> "));
		Serial.println(requestVal);
		request = static_cast<REQUEST_TYPE>(requestVal);
	}else{
		Serial.print(F("No parameter received!"));
	}
}