Send multiple variable values between 2 Arduinos over I2C

Projects Networking, Protocols, and Devices
12

You can more easily communicate over I2C using SerialTransfer.h.

Directions on how to install.

Here's an example:

TX:

#include "I2CTransfer.h"


I2CTransfer myTransfer;

struct STRUCT {
  char z;
  float y;
} testStruct;

char arr[] = "hello";


void setup()
{
  Serial.begin(115200);
  Wire.begin();

  myTransfer.begin(Wire);

  testStruct.z = '$';
  testStruct.y = 4.5;
}


void loop()
{
  // use this variable to keep track of how many
  // bytes we're stuffing in the transmit buffer
  uint16_t sendSize = 0;

  ///////////////////////////////////////// Stuff buffer with struct
  sendSize = myTransfer.txObj(testStruct, sendSize);

  ///////////////////////////////////////// Stuff buffer with array
  sendSize = myTransfer.txObj(arr, sendSize);

  ///////////////////////////////////////// Send buffer
  myTransfer.sendData(sendSize);
  delay(500);
}

RX:

#include "I2CTransfer.h"


I2CTransfer myTransfer;

struct STRUCT {
  char z;
  float y;
} testStruct;

char arr[6];


void hi()
{
  // use this variable to keep track of how many
  // bytes we've processed from the receive buffer
  uint16_t recSize = 0;

  recSize = myTransfer.rxObj(testStruct, recSize);
  Serial.print(testStruct.z);
  Serial.print(testStruct.y);
  Serial.print(" | ");

  recSize = myTransfer.rxObj(arr, recSize);
  Serial.println(arr);
}

// supplied as a reference - persistent allocation required
const functionPtr callbackArr[] = { hi };


void setup()
{
  Serial.begin(115200);
  Wire.begin(0);

  configST myConfig;
  myConfig.debug        = true;
  myConfig.callbacks    = callbackArr;
  myConfig.callbacksLen = sizeof(callbackArr) / sizeof(functionPtr);
  
  myTransfer.begin(Wire, myConfig);
}


void loop()
{
  // Do nothing
}