Hauwa Lawan

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12 years, 8 months ago.

Arduino + Mbed i2c?

Hello.

I am currently working on a project that requires me to send data from the mbed to the arduino using i2c... Does anyone have an idea of how i can do this? This is what i have tried so far.

mbed master code

#include "mbed.h"

Serial rn42(p9,p10);
DigitalOut myled(LED1);
I2C i2c (p28,p27);
int x;
int main()
{

    rn42.baud(115200);

    while (1) {
        if (rn42.readable()) {
            x = rn42.getc();
            printf("%d\n",x);
            myled = !myled;
            i2c.start();
            i2c.write(0xC0);
            i2c.write(x);
            i2c.stop();
        }
    }
}

arduino slave code

#include <Wire.h>

byte y;


void setup()
{

  Serial.begin(115200);
  Wire.begin(0xC0);
}

void loop()
{

Wire.onReceive(receiveEvent);  

}

void receiveEvent(int howMany)
{
  
   y = Wire.read();
   Serial.println (y); 
     
}

Thank you very much.

2 Answers

Jock Murphy
7 years, 8 months ago.

Be aware that mBed i2c addresses are shifted 1 bit to the left. So if you use the I2C address 0x0F (00001111) on the arduino, it will be 0x1E (00011110) on mBed

Scott Kirkwood
10 years ago.

I'm in the same boat. Arduino (Master) sending messages to mbed (slave or another master). Has this already been mastered?