//  Week 15 - Networking and Communications
//  ATtiny44A board, 20 Mhz external clock
//  Network node 2
//
//  Author: Jari Uusitalo
//  Modified by Kati Pitkänen on May 31, 2018
//  ATtiny45 board, 8 Mhz internal clock, Network NODE 1

#include <SoftwareSerial.h>

#define rxPin 2                             // 0 as INPUT receives request from the Bridge board
#define txPin 0                             // 2 as OUTPUT transmits data to the Bridge board

SoftwareSerial mySerial(rxPin, txPin);      // Set up Serial Port RX, TX

const char node = '1';                      // Network address of this NODE2 board

const int ledPin = 2;                       // Green LED is in OUTPUT pin 2
char incomingbyte;                          // Variable to store the data (NODE2)

int lightSensPin = 3;                       // Declare the lightSensPin as an INPUT
int sensorValueL = 0;                       // Variable to store the value coming from the light sensor
char reading;
int threshold = 200;

void setup() {

  pinMode(ledPin, OUTPUT);                  // Green LED is OUTPUT
  pinMode(rxPin, INPUT);                    // RX is INPUT
  pinMode(sensorValueL, INPUT);

  mySerial.begin(9600);                     // Open Serial communication between NODEs and Bridge (data rate 9600 bps)
}


void loop() {

    sensorValueL = analogRead(lightSensPin);
    
    while(mySerial.available())             // Waits for node to be available and response through serial
     {
          incomingbyte = mySerial.read();   // Read the incoming byte

          if(incomingbyte == '1') {

          pinMode(txPin, OUTPUT);           // Change TX as OUPUT to send a signal to the BRIDGE
      
          if (sensorValueL < threshold){    // SensorValueL increases in the dark - when LOW, it is BRIGHT
            reading = 'L';
          }
          else {
            reading = 'H';                  // SensorValuL decreases in the dark - when HIGH, it is DARK
          }
          
          mySerial.print(reading);  
          /*    
              digitalWrite(ledPin, HIGH);   // Blink the green LED as a sign that the request is received
              delay(500);
              digitalWrite(ledPin, LOW);
*/
          pinMode(txPin, INPUT);            // Change TX back as INPUT to listen a request of the BRIDGE
          }
          else {
          }
      }
}