/* Outside transmitter
 *  
 * 
 * 
 * Send data via RF 433MHz to receiver
 * 
 * CONNECTIONS
 * RF 433MHz: VCC -> 5V
              GND -> GND
              Data -> D12
 * Si7021:     VCC -> 5V
              GND -> GND
              SCL -> SCL
              SDA -> SDA
 
 */




#include <VirtualWire.h>
#include <Wire.h>
#include "SPI.h"   // Is it really neaded for BMP280 SPI?
#include "Adafruit_Si7021.h"


Adafruit_Si7021 sensor = Adafruit_Si7021();
#include "LowPower.h"

int ledPin = 13;
char Msg[30];// The string that we are going to send trought rf transmitter 
 
void setup() 
{
  Serial.begin(9600);
  
  sensor.begin();
  
  pinMode(ledPin,OUTPUT); // Set LED at D13 as output
  
  // VirtualWire setup
  vw_setup(2000); // Bits per sec for RF
  vw_set_tx_pin(12);// Set the Tx pin. Default is 12
}
 
void loop() {
  
  // si7021 Read and store values
  float humidity_float = sensor.readHumidity();
  float temp_float = sensor.readTemperature();

  // For debugging
  Serial.println("VALUES READ:");
  Serial.print("Temperature: ");
  Serial.print(temp_float);
  Serial.println("C");
  Serial.print("Humidity: ");
  Serial.print(humidity_float);
  Serial.println("%");
  Serial.println();
  
  // Convert si7021 float values to integers to be send by RF with 2 decimal point precision

  temp_float = temp_float * 100;   // Multiply by 100 for 2 decimal point precision
  int b = int(temp_float);    // http://forum.arduino.cc/index.php?topic=82462.0
  int temperature = round(b);    // Round float number to nearest integer
  
  humidity_float = humidity_float * 100;   // Multiply by 100 for 2 decimal point precision
  int a = int(humidity_float);    // http://forum.arduino.cc/index.php?topic=82462.0
  int humidity = round(a);    // Round float number to nearest integer


  // Send message through RF  
  sprintf(Msg, "%d,%d", humidity,temperature);
 // Turn on a light to show transmitting
  Serial.println("Read Values OK!");
  digitalWrite(ledPin, HIGH); 
  delay(1000); 
  vw_send((uint8_t *)Msg, strlen(Msg));
  vw_wait_tx(); // Wait until the whole message is gone
  digitalWrite(ledPin, LOW);  // Turn off a light after transmission
  
 // Lowpower library supports max sleep time of 8s 
 // use loop as many times as needed to achieve longer sleep
 //30 * 8s = 240s 
  for(int i=0;i<30;i++) // sleep for 4 minutes
  {
 LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF); }

  }