// Wire Master Reader // by devyte // based on the example of the same name by Nicholas Zambetti // Demonstrates use of the Wire library // Reads data from an I2C/TWI slave device // Refer to the "Wire Slave Sender" example for use with this // This example code is in the public domain. #include #include #define SDA_PIN 4 #define SCL_PIN 5 const int16_t I2C_MASTER = 0x42; const int16_t I2C_SLAVE = 0x08; void setup() { Serial.begin(115200); // start serial for output Wire.begin(SDA_PIN, SCL_PIN, I2C_MASTER); // join i2c bus (address optional for master) } void loop() { using periodic = esp8266::polledTimeout::periodic; static periodic nextPing(1000); if (nextPing) { Wire.requestFrom(I2C_SLAVE, 6); // request 6 bytes from slave device #8 while (Wire.available()) { // slave may send less than requested char c = Wire.read(); // receive a byte as character Serial.print(c); // print the character } } }