//Master Arduino Code: //SPI MASTER (ARDUINO) //SPI COMMUNICATION BETWEEN TWO ARDUINO //CIRCUIT DIGEST #include //Library for SPI #define LED 7 #define ipbutton 2 int buttonvalue; int x; void setup (void) { Serial.begin(115200); //Starts Serial Communication at Baud Rate 115200 pinMode(ipbutton,INPUT); //Sets pin 2 as input pinMode(LED,OUTPUT); //Sets pin 7 as Output SPI.begin(); //Begins the SPI commnuication SPI.setClockDivider(SPI_CLOCK_DIV8); //Sets clock for SPI communication at 8 (16/8=2Mhz) digitalWrite(SS,HIGH); // Setting SlaveSelect as HIGH (So master doesnt connnect with slave) } void loop(void) { byte Mastersend,Mastereceive; buttonvalue = 8; digitalWrite(SS, LOW); //Starts communication with Slave connected to master Mastersend = buttonvalue; Mastereceive=SPI.transfer(Mastersend); //Send the mastersend value to slave also receives value from slave Serial.println(Mastereceive); delay(50); }