diff --git a/BMP280.h b/BMP280.h
index f6a2949..4722f4b 100644
--- a/BMP280.h
+++ b/BMP280.h
@@ -3,7 +3,7 @@
 
 #include "softspim.h"
 
-#define PRECOMP_COMPENSATION
+//#define PRECOMP_COMPENSATION
 
 class BMP280
 {
diff --git a/W433DataTransmitter.cpp b/W433DataTransmitter.cpp
index ececa05..1065d75 100644
--- a/W433DataTransmitter.cpp
+++ b/W433DataTransmitter.cpp
@@ -1,7 +1,7 @@
 #include "W433DataTransmitter.h"
 #include "writepin.h"
 
-W433DataTransmitter::W433DataTransmitter(volatile unsigned char *port, unsigned char pin): _port(port), _pin(pin)
+W433DataTransmitter::W433DataTransmitter(volatile unsigned char *port, const unsigned char pin): _port(port), _pin(pin)
 {
 }
 
@@ -10,7 +10,7 @@ void W433DataTransmitter::sendBit(const bool bit)
     switch(bit)
     {
         case true:
-        writePin(_port,_pin,true);
+		writePin(_port,_pin,true);
         _delay_us(SMALL_TIME);
         writePin(_port,_pin,false);
         _delay_us(LARGE_TIME);
diff --git a/W433DataTransmitter.h b/W433DataTransmitter.h
index 8d3304e..a6ed52c 100644
--- a/W433DataTransmitter.h
+++ b/W433DataTransmitter.h
@@ -14,7 +14,7 @@ private:
     
     static constexpr uint8_t signature = 0xA5;
     volatile unsigned char * const _port;
-    unsigned char _pin;
+    const unsigned char _pin;
     
     void sendBit(const bool bit);
     void sendSyncpulse();
@@ -23,9 +23,8 @@ private:
     
 public:
     
-    W433DataTransmitter(volatile unsigned char * const port, unsigned char pin);
+    W433DataTransmitter(volatile unsigned char * const port, const unsigned char pin);
     void send(const uint8_t* const data, uint16_t length);
     void send(const uint8_t data);
     void sendPacket(const uint32_t data);
-    
 };
diff --git a/dht11.cpp b/dht11.cpp
index f1c2dc3..d8920ef 100644
--- a/dht11.cpp
+++ b/dht11.cpp
@@ -1,6 +1,6 @@
 #include "dht11.h"
 
-Dht11::Dht11(volatile unsigned char *port, volatile unsigned char *inPort, volatile unsigned char *port_ctl, const unsigned char pin): _port(port), _inPort(inPort), _port_ctl(port_ctl), _pin(pin)
+Dht11::Dht11(volatile unsigned char * const port, volatile unsigned char * const inPort, volatile unsigned char * const port_ctl, const unsigned char pin): _port(port), _inPort(inPort), _port_ctl(port_ctl), _pin(pin)
 {}
 
 uint8_t Dht11::read()
@@ -53,9 +53,7 @@ uint8_t Dht11::read()
 		}
 		else cnt--;
 	}
-
-	// WRITE TO RIGHT VARS
-        // as bits[1] and bits[3] are allways zero they are omitted in formulas.
+	
 	uint8_t sum;
 	if constexpr(DHT22) sum= bits[0] + bits[1] + bits[2] + bits[3];
 	else sum = bits[1] + bits[3];
diff --git a/dht11.h b/dht11.h
index fbd0973..b1cb7e4 100644
--- a/dht11.h
+++ b/dht11.h
@@ -16,7 +16,7 @@ class Dht11
     const unsigned char _pin;
     
 public:
-    Dht11(volatile unsigned char *port, volatile unsigned char *inPort, volatile unsigned char *port_ctl, const unsigned char pin);
+    Dht11(volatile unsigned char * const port, volatile unsigned char * const inPort, volatile unsigned char * const port_ctl, const unsigned char pin);
     uint8_t read();
     int16_t humidity = 0;
     uint16_t temperature = 0;
diff --git a/main.cpp b/main.cpp
index 179c685..b7b6959 100644
--- a/main.cpp
+++ b/main.cpp
@@ -8,6 +8,7 @@
 #include "watchdog.h"
 #include "softspim.h"
 #include "BMP280.h"
+#include "comperator.h"
 
 #define TEMP_SENSOR_DATA PB4
 #define TRANSMITTER_DATA PD0
@@ -15,10 +16,12 @@
 #define POWER_PIN PD5
 #define LED_PIN PD1
 
-EMPTY_INTERRUPT( WDT_OVERFLOW_vect);
+EMPTY_INTERRUPT(WDT_OVERFLOW_vect);
 
-static constexpr uint8_t id = 1;
+static constexpr uint8_t id = 3;
 static constexpr bool WATCH_DOOR = false;
+static constexpr bool BMP_280 = false;
+static constexpr bool DHT22   = true;
 
 
 static void power(const bool power)
@@ -27,16 +30,25 @@ static void power(const bool power)
 	{
 		PORTD |= 1 << POWER_PIN | 1 << LED_PIN;
 		DDRD = 1 << POWER_PIN | 1 << LED_PIN | 1 << TRANSMITTER_DATA;
-		DDRB = 1 << PB0 | 1 << PB1 | 1 << PB3;
+		DDRB = 1 << PB0 | 1 << PB3;
 	}
 	else 
 	{
 		PORTD &= ~(1 << POWER_PIN | 1 << LED_PIN | 1 << TRANSMITTER_DATA);
-		//DDRD &= ~(1 << TRANSMITTER_DATA);
 		DDRB = 0;
 	}
 }
 
+void debugBlink(bool fast = true)
+{
+	_delay_ms(100);
+	if(!fast) _delay_ms(200); 
+	PORTD &= ~(1 << LED_PIN);
+	_delay_ms(100);
+	if(!fast) _delay_ms(200); 
+	PORTD |= 1 << LED_PIN;
+}
+
 int main()
 {
 
@@ -49,53 +61,88 @@ int main()
 	//Transmitter and transmiter power
 	W433DataTransmitter transmiter(&PORTD, TRANSMITTER_DATA);
 	
+	Comperator comp;
+	
 	sei();
 	
 	wdt_set(WDTO_8S);
 	set_sleep_mode(SLEEP_MODE_PWR_DOWN);
 	
-	uint8_t couter = 50;
+	uint8_t couter = 200;
 	
 	while(true)
 	{
-		if(++couter > 1) 
+		if(++couter > 80)
 		{
 			couter = 0;
 		
 			power(true);
-			_delay_ms(2000);
+			comp.on();
+			for(uint8_t i = 0; i < 20; ++i)
+			{
+				debugBlink();
+			}
+			PORTD &= ~(1 << LED_PIN);
+			
+			uint32_t paketUint;
+			uint8_t * const paket = reinterpret_cast<uint8_t*>(&paketUint);
+			paket[1] = id;
+
 			
 			//temperature sensor
-			tempSensor.read();
-			uint8_t paket[4]; 
-			paket[0] = 1;
-			paket[1] = id;
-			paket[2] = tempSensor.temperature >> 8;
-			paket[3] = tempSensor.temperature;
-			transmiter.send(paket, 4);
+			if constexpr (DHT22)
+			{
+				debugBlink(false);
+				uint8_t readret;
+				readret = tempSensor.read(); 
+				paket[0] = 1;
+				paket[2] = tempSensor.temperature >> 8;
+				paket[3] = tempSensor.temperature;
+				transmiter.sendPacket(paketUint);
+			}
 			
 			//humidity sensor
-			paket[0] = 2;
-			paket[2] = tempSensor.humidity >> 8;
-			paket[3] = tempSensor.humidity;
-			transmiter.send(paket, 4);
+			if constexpr (DHT22)
+			{
+				debugBlink(false);
+				paket[0] = 2;
+				paket[2] = tempSensor.humidity >> 8;
+				paket[3] = tempSensor.humidity;
+				transmiter.sendPacket(paketUint);
+			}
+			
+			//low battery waring
+			if(comp.compare())
+			{
+				debugBlink(false);
+				paket[0] = 128;
+				paket[2] = 0;
+				paket[3] = 1;
+				transmiter.sendPacket(paketUint);
+			}
 			
 			//presure sensor
-			uint16_t pressure = pressSensor.getPressure();
-			paket[0] = 3;
-			paket[2] = pressure >> 8;
-			paket[3] = pressure;
-			transmiter.send(paket, 4);
+			if constexpr(BMP_280)
+			{
+				debugBlink(false);
+				uint16_t pressure = pressSensor.getPressure();
+				paket[0] = 3;
+				paket[2] = pressure >> 8;
+				paket[3] = pressure;
+				transmiter.sendPacket(paketUint);
+			}
 			
 			//door
 			if constexpr(WATCH_DOOR)
 			{
+				debugBlink(false);
 				paket[0] = 0;
 				paket[1] = 2;
 				paket[2] = 0;
 				paket[3] = readPin(&PIND, DOOR_PIN); 
-				transmiter.send(paket, 4);
+				transmiter.sendPacket(paketUint);
 			}
+			comp.off();
 			power(false);
 		}
 		sleep_mode();
diff --git a/softspim.h b/softspim.h
index bb31f1c..65567b3 100644
--- a/softspim.h
+++ b/softspim.h
@@ -10,8 +10,8 @@ private:
 	static constexpr uint8_t CLOCK_PHASE    = 1;
 	static constexpr uint8_t BIT_ORDER      = 1;
 
-    volatile uint8_t *_port        = &PORTB;
-    volatile uint8_t *_pinReg      = &PINB;
+    volatile uint8_t * const _port        = &PORTB;
+    volatile uint8_t * const _pinReg      = &PINB;
     static constexpr uint8_t _pinIn       = PB2;
     static constexpr uint8_t _pinOut      = PB0;
     static constexpr uint8_t _pinClock    = PB3;
diff --git a/watchdog.h b/watchdog.h
index de49320..c683aa0 100644
--- a/watchdog.h
+++ b/watchdog.h
@@ -9,7 +9,7 @@
         "sts %0,%1" "\n\t"  \
         "out __SREG__,__tmp_reg__" "\n\t"   \
         "sts %0,%2" \
-        : /* no outputs */  \
+        :  \
         : "M" (_SFR_MEM_ADDR(_WD_CONTROL_REG)), \
         "r" (_BV(_WD_CHANGE_BIT) | _BV(WDE)), \
 			   "r" ((uint8_t) ((value & 0x08 ? _WD_PS3_MASK : 0x00) | \
@@ -25,7 +25,7 @@
         "wdr" "\n\t"    \
         "sts %0,%1" "\n\t"  \
         "sts %0,%2" \
-        : /* no outputs */  \
+        : \
         : "M" (_SFR_MEM_ADDR(_WD_CONTROL_REG)), \
         "r" (_BV(_WD_CHANGE_BIT) | _BV(WDE)), \
 			   "r" ((uint8_t) (0x00)) \
diff --git a/writepin.cpp b/writepin.cpp
index 744a47d..2caaf88 100644
--- a/writepin.cpp
+++ b/writepin.cpp
@@ -1,19 +1,20 @@
 #include "writepin.h"
 
-void writePin(volatile unsigned char *port, const unsigned char pin, const bool state) //waste 2 cycles
+void writePin(volatile unsigned char * const port, const unsigned char pin, const bool state)
 {
-    if(!state) *port  &= ~(1 << pin);
-    else *port |= (1 << pin);
+	*port = (*port & ~(1 << pin)) | (1 << pin)*state;
+    //if(!state) *port &= ~(1 << pin);
+    //else *port |= (1 << pin);
 }
 
-void setBit( volatile unsigned char *reg, const unsigned char bit, bool value )
+void setBit( volatile unsigned char * const reg, const unsigned char bit, const bool value )
 {
     writePin(reg, bit, value);
 }
 
-void setDirection( volatile unsigned char *portDirReg, const unsigned char pin, bool makeOutput )
+void setDirection( volatile unsigned char * const portDirReg, const unsigned char pin, const bool makeOutput )
 {
     writePin(portDirReg, pin, makeOutput);
 }
 
-bool readPin( volatile unsigned char *inPort, const unsigned char pin){ return (bool) (*inPort & (1 << pin));}
+bool readPin( volatile const unsigned char * const inPort, const unsigned char pin){ return (bool) (*inPort & (1 << pin));}
diff --git a/writepin.h b/writepin.h
index 616d4c5..0cf8943 100644
--- a/writepin.h
+++ b/writepin.h
@@ -2,13 +2,12 @@
 #define WRITEPIN_H
 #include <avr/io.h>
 
+void  writePin(volatile unsigned char * const port, const unsigned char pin, const bool state);
 
-void  writePin(volatile unsigned char *port, const unsigned char pin, const bool state);
+void setBit( volatile unsigned char * const reg, const unsigned char bit, const bool value );
 
-void setBit( volatile unsigned char *reg, const unsigned char bit, bool value );
+void setDirection( volatile unsigned char * const portDirReg, const unsigned char pin, const bool makeOutput );
 
-void setDirection( volatile unsigned char *portDirReg, const unsigned char pin, bool makeOutput );
-
-bool readPin( volatile unsigned char *inPort, const unsigned char pin);
+bool readPin( volatile const unsigned char * const inPort, const unsigned char pin);
 
 #endif