I am using Python smbus write_word_data method to send int values from a Raspberry Pi to an Arduino using I²C.

This seems to be the correct method.

When I send values from 0-255, I see the following in my arduino serial monitor

0,0,0
0,1,0
0,2,0
…
0,255,0

Sending 256 I see
 

0,0,1

for 257 I see
0,1,1

etc etc

My question is how would I modify the following arduino code to properly 'reconstitute' the int values, and then send them back to the RPi?

 #include <Wire.h>    #define SLAVE_ADDRESS 0x04  int number = 0;  int state = 0; bool newData = false;    void setup() {   pinMode(13, OUTPUT);   Serial.begin(9600); // start serial for output   // initialize i2c as slave   Wire.begin(SLAVE_ADDRESS);   // define callbacks for i2c communication   Wire.onReceive(receiveData);   Wire.onRequest(sendData);   Serial.println("Ready!");  }    void loop() {   Serial.println(receivedValue);    newData=false; } }  // callback for received data  void receiveData(int byteCount){    while(Wire.available()) {   newData = true;    Wire.read();   if(Wire.available() == 2)  { receivedValue = Wire.read() | Wire.read() << 8; }   }    }    // callback for sending data  void sendData(){    Wire.write(number);  } 

I am using Python smbus write_word_data method to send int values from a Raspberry Pi to an Arduino using I²C.

This seems to be the correct method.

When I send values from 0-255, I see the following in my Arduino serial monitor

0,0,0
0,1,0
0,2,0
…
0,255,0

Sending 256 I see:

0,0,1

For 257 I see:

0,1,1

Etc, etc...

My question is, how would I modify the following Arduino code to properly 'reconstitute' the int values, and then send them back to the RPi?

#include <Wire.h> #define SLAVE_ADDRESS 0x04 int number = 0; int state = 0; bool newData = false; void setup() { pinMode(13, OUTPUT); Serial.begin(9600); // initialize i2c as slave Wire.begin(SLAVE_ADDRESS); // define callbacks for i2c communication Wire.onReceive(receiveData); Wire.onRequest(sendData); Serial.println("Ready!"); } void loop() { Serial.println(receivedValue); newData=false; } // callback for received data void receiveData(int byteCount) { while(Wire.available()) { newData = true; Wire.read(); if(Wire.available() == 2) {   receivedValue = Wire.read() | Wire.read() << 8; } } }   // callback for sending data void sendData() { Wire.write(number); } 

I am using Python smbus write_word_data method to send int values from a Raspberry Pi to an arduino.

0,0,0
0,1,0
0,2,0
etc
0,255,0

My question is how would I modify the following arduino code to properly 'reconsitute' the int values, and then send them back to the RPi?

 #include <Wire.h> #define SLAVE_ADDRESS 0x04 int number = 0; int state = 0; bool newData = false; void setup() { pinMode(13, OUTPUT); Serial.begin(9600); // start serial for output // initialize i2c as slave Wire.begin(SLAVE_ADDRESS); // define callbacks for i2c communication Wire.onReceive(receiveData); Wire.onRequest(sendData); Serial.println("Ready!"); } void loop() { Serial.println(receivedValue); newData=false; } } // callback for received data void receiveData(int byteCount){ while(Wire.available()) { newData = true; Wire.read(); if(Wire.available() == 2) { receivedValue = Wire.read() | Wire.read() << 8; } } } // callback for sending data void sendData(){ Wire.write(number); } 

I am using Python smbus write_word_data method to send int values from a Raspberry Pi to an Arduino using I²C.

0,0,0
0,1,0
0,2,0
…
0,255,0

My question is how would I modify the following arduino code to properly 'reconstitute' the int values, and then send them back to the RPi?

 #include <Wire.h> #define SLAVE_ADDRESS 0x04 int number = 0; int state = 0; bool newData = false; void setup() { pinMode(13, OUTPUT); Serial.begin(9600); // start serial for output // initialize i2c as slave Wire.begin(SLAVE_ADDRESS); // define callbacks for i2c communication Wire.onReceive(receiveData); Wire.onRequest(sendData); Serial.println("Ready!"); } void loop() { Serial.println(receivedValue); newData=false; } } // callback for received data void receiveData(int byteCount){ while(Wire.available()) { newData = true; Wire.read(); if(Wire.available() == 2) { receivedValue = Wire.read() | Wire.read() << 8; } } } // callback for sending data void sendData(){ Wire.write(number); } 

#include <Wire.h> #define SLAVE_ADDRESS 0x04 int number = 0; int state = 0; void setup() { pinMode(13, OUTPUT); Serial.begin(9600); // start serial for output // initialize i2c as slave Wire.begin(SLAVE_ADDRESS); // define callbacks for i2c communication Wire.onReceive(receiveData);  Wire.onRequest(sendData);   Serial.println("Ready!"); } void loop() {  delay(100); }  // callback for received data void receiveData(int byteCount){  while(Wire.available()) {  number = Wire.read();   Serial.print("data received: ");  Serial.println(number);     if (number == 1){ if (state == 0){   digitalWrite(13, HIGH); // set the LED on   state = 1;   }   else{   digitalWrite(13, LOW); // set the LED off   state = 0;   }  }     } } // callback for sending data void sendData(){ Wire.write(number); } 

 #include <Wire.h>    #define SLAVE_ADDRESS 0x04  int number = 0;  int state = 0; bool newData = false;  void setup() {   pinMode(13, OUTPUT);   Serial.begin(9600); // start serial for output   // initialize i2c as slave   Wire.begin(SLAVE_ADDRESS);     // define callbacks for i2c communication Wire.onReceive(receiveData); Wire.onRequest(sendData); Serial.println("Ready!"); }    void loop() {  Serial.println(receivedValue); newData=false;  } }     // callback for received data  void receiveData(int byteCount){    while(Wire.available()) { newData = true;    Wire.read(); if(Wire.available() == 2)  { receivedValue = Wire.read() | Wire.read() << 8; } }    } // callback for sending data  void sendData(){     Wire.write(number);  }