ぱぱーんの日記

int型の変数の値を読みたいということと、２バイトのレジスターの値を読みたいということで受信側のソフトウエアも修正しました。

slave_receiver2

// Wire Slave Receiver
// by Nicholas Zambetti <http://www.zambetti.com>

// Demonstrates use of the Wire library
// Receives data as an I2C/TWI slave device
// Refer to the "Wire Master Writer" example for use with this

// Created 29 March 2006

// This example code is in the public domain.


#include <Wire.h>

void setup() {
  Wire.begin(8);                // join i2c bus with address #8
  Wire.onReceive(receiveEvent); // register event
  Serial.begin(230400);        // start serial for output
}

void loop() {
  delay(100);
}

// function that executes whenever data is received from master
// this function is registered as an event, see setup()
char c;
int x, y;

void receiveEvent(int howMany) {
  while (2 < Wire.available()) { // loop through all but the last
    c = Wire.read();             // receive byte as a character
    if (c == '*'){
      break;
    }
    Serial.print(c);       // print the character
  }
  Serial.print(" is ");
 
  if (c == '*'){
    //debugRegPrint
    x = Wire.read();
    y = Wire.read();   // receive byte as an integer
    x = 256 * y + x;
    Serial.print("0x");
    Serial.println(x, HEX);// print the integer

  } else {
    //debugPrint
    x = Wire.read();
    y = Wire.read();   // receive byte as an integer
    x = 256 * y + x;
    Serial.println(x);// print the integer
  }
}

void receiveEvent(int howMany)を修正しました。

文字列の最後が「*」で終わると、HEXとして処理します。それ以外はint型として処理します。