diff --git a/firmware/at.c b/firmware/at.c
index 77a88e0..51f4da3 100644
--- a/firmware/at.c
+++ b/firmware/at.c
@@ -7,6 +7,7 @@
 #include "at.h"
 #include "uart.h"
 #include "config.h"
+#include "nightm.h"
 #include "time.h"
 #include "led.h"
 #include "rtc.h"
@@ -18,7 +19,8 @@ const struct AT_CMD at_commands[AT_NUM] PROGMEM = {
   { "ATI", cmd_ati_handler },
   { "AT+RST", cmd_at_rst_handler },
   { "AT+TIME", cmd_at_time_handler },
-  { "AT+BTNES", cmd_at_btnes_handler }
+  { "AT+BTNES", cmd_at_btnes_handler },
+  { "AT+NGT", cmd_at_ngt_handler }
 };
 
 void parse_at(char* at_cmd, char* arg, uint8_t mode)
@@ -115,7 +117,7 @@ int8_t cmd_at_rst_handler(uint8_t mode, char* arg)
 
 int8_t cmd_at_time_handler(uint8_t mode, char* arg)
 {
-  struct TIME time;
+  struct TIME_HMS time;
   char* val;
   char* tail;
 
@@ -171,8 +173,7 @@ int8_t cmd_at_btnes_handler(uint8_t mode, char* arg)
   switch(mode)
   {
     case M_GET:    
-      for(btness=0; btness<8; ++btness) if(ram_cfg.led_brightness & (1<<btness)) break;
-      uart_puti(btness, 10);
+      uart_puti(ram_cfg.led_brightness, 10);
       uart_puts("\n\r");
 
       break;
@@ -196,3 +197,69 @@ int8_t cmd_at_btnes_handler(uint8_t mode, char* arg)
 
   return 0;
 }
+
+int8_t cmd_at_ngt_handler(uint8_t mode, char* arg)
+{
+  struct NIGHTM_CFG nightm_cfg;
+  char* val;
+  char* tail;
+
+  switch(mode)
+  {
+    case M_GET:
+      uart_puti(ram_cfg.night_mode.led_btnes, 10);
+      uart_puts(ram_cfg.night_mode.led_btnes >= 0 ? " (EN)\n\r" : " (DIS)\n\r");
+      uart_puti(ram_cfg.night_mode.begin.hour, 10);
+      uart_puts(":");
+      uart_puti(ram_cfg.night_mode.begin.minute, 10);
+      uart_puts("\n\r");
+      uart_puti(ram_cfg.night_mode.end.hour, 10);
+      uart_puts(":");
+      uart_puti(ram_cfg.night_mode.end.minute, 10);
+      uart_puts("\n\r");
+      break;
+    
+    case M_SET:
+      if(!strlen(arg)) return -1;
+
+      val = strtok_r(arg, ",", &tail);
+      nightm_cfg.led_btnes = atoi(val);
+      if(nightm_cfg.led_btnes < -1 && 7 < nightm_cfg.led_btnes) return -1;
+
+      val = strtok_r(NULL, ",", &tail);
+      nightm_cfg.begin.hour = atoi(val);
+      if(nightm_cfg.begin.hour > 23) return -1;
+
+      val = strtok_r(NULL, ",", &tail);
+      nightm_cfg.begin.minute = atoi(val);
+      if(nightm_cfg.begin.minute > 59) return -1;
+
+      val = strtok_r(NULL, ",", &tail);
+      nightm_cfg.end.hour = atoi(val);
+      if(nightm_cfg.end.hour > 23) return -1;
+
+      val = strtok_r(NULL, ",", &tail);
+      nightm_cfg.end.minute = atoi(val);
+      if(nightm_cfg.end.minute > 59) return -1;
+
+      nightm_config(&nightm_cfg);
+
+      uart_puts("+NGT=");
+      uart_puti(nightm_cfg.led_btnes, 10);
+      uart_puts(",");
+      uart_puti(nightm_cfg.begin.hour, 10);
+      uart_puts(",");
+      uart_puti(nightm_cfg.begin.minute, 10);
+      uart_puts(",");
+      uart_puti(nightm_cfg.end.hour, 10);
+      uart_puts(",");
+      uart_puti(nightm_cfg.end.minute, 10);
+      uart_puts("\n\r");
+      break;
+
+    case M_NORM:
+      uart_puts("AT+NGT=(-1|0-7),(0-23),(0-59),(0-23),(0-59)");
+  }
+
+  return 0;
+}
\ No newline at end of file
diff --git a/firmware/at.h b/firmware/at.h
index 5e782f2..a527e7d 100644
--- a/firmware/at.h
+++ b/firmware/at.h
@@ -20,8 +20,9 @@ int8_t cmd_ati_handler(uint8_t mode, char* arg);
 int8_t cmd_at_rst_handler(uint8_t mode, char* arg);
 int8_t cmd_at_time_handler(uint8_t mode, char* arg);
 int8_t cmd_at_btnes_handler(uint8_t mode, char* arg);
+int8_t cmd_at_ngt_handler(uint8_t mode, char* arg);
 
-#define AT_NUM 5
+#define AT_NUM 6
 extern const struct AT_CMD at_commands[AT_NUM] PROGMEM;
 
 #endif
\ No newline at end of file
diff --git a/firmware/config.c b/firmware/config.c
index 5f2c0cd..18e3869 100644
--- a/firmware/config.c
+++ b/firmware/config.c
@@ -3,7 +3,8 @@
 struct CFG ram_cfg;
 struct CFG eem_cfg EEMEM;
 const struct CFG pgm_cfg PROGMEM = {
-  LED_BRIGHTNESS
+  LED_BRIGHTNESS,
+  NIGHT_MODE
 };
 
 void map_eem2ram(void)
diff --git a/firmware/config.h b/firmware/config.h
index 439d732..1678444 100644
--- a/firmware/config.h
+++ b/firmware/config.h
@@ -3,12 +3,24 @@
 
 #include <avr/eeprom.h>
 #include <avr/pgmspace.h>
+#include "time.h"
 
-#define LED_BRIGHTNESS 127
+#define AUTO_BTNES_SIZE 4
+
+#define LED_BRIGHTNESS 7
+#define NIGHT_MODE { -1, { 0, 0 }, { 0, 0 } }
+
+struct NIGHTM_CFG
+{
+  int8_t led_btnes;
+  struct TIME_HM begin;
+  struct TIME_HM end;
+};
 
 struct CFG
 {
   uint8_t led_brightness;
+  struct NIGHTM_CFG night_mode;
 };
 
 extern struct CFG ram_cfg;
diff --git a/firmware/led.c b/firmware/led.c
index 4bcef2f..4b4cc63 100644
--- a/firmware/led.c
+++ b/firmware/led.c
@@ -3,10 +3,14 @@
 #include "config.h"
 #include "led.h"
 
-volatile struct TIME led_display = { 0, 0, 0 };
+volatile struct TIME_HMS led_display = { 0, 0, 0 };
+volatile uint8_t led_btnes;
 
 void led_init(void) 
 {
+  // Set brightness
+  led_btnes = 1<<(ram_cfg.led_brightness);
+
   // Set outputs
   ANODES_DIR |= HOUR_ANODE | MINUTE_ANODE | SECOND_ANODE; 
   LED_DIR |= 0x3F; // 0b00111111
@@ -19,17 +23,18 @@ void led_init(void)
   TIMSK |= (1<<TOIE0);
 }
 
-void led_set_btness(uint8_t btness)
+void led_set_btness(uint8_t btnes)
 {
-  ram_cfg.led_brightness = (1<<btness);
-  if(!ram_cfg.led_brightness) ram_cfg.led_brightness = 1;
+  if(btnes > 7) btnes = 0;
+  led_btnes = 1<<btnes;  
+  ram_cfg.led_brightness = btnes;
   dump_ram2eem();
 }
 
 void led_inc_btness(void)
 {
-  ram_cfg.led_brightness <<= 1;
-  if(!ram_cfg.led_brightness) ram_cfg.led_brightness = 1;
+  if(++(ram_cfg.led_brightness) > 7) ram_cfg.led_brightness = 0;
+  led_btnes = 1<<(ram_cfg.led_brightness);
   dump_ram2eem();
 }
 
@@ -44,15 +49,15 @@ ISR(TIMER0_OVF_vect)
   {
     case 1: 
       LED_PORT = ~led_display.hour;   
-      ANODES_PORT = ram_cfg.led_brightness >= pwm_counter ? ~HOUR_ANODE : 0xFF;
+      ANODES_PORT = led_btnes >= pwm_counter ? ~HOUR_ANODE : 0xFF;
       break;
     case 2: 
       LED_PORT = ~led_display.minute;   
-      ANODES_PORT = ram_cfg.led_brightness >= pwm_counter ? ~MINUTE_ANODE : 0xFF;  
+      ANODES_PORT = led_btnes >= pwm_counter ? ~MINUTE_ANODE : 0xFF;  
       break;
     case 4: 
       LED_PORT = ~led_display.second;
-      ANODES_PORT = ram_cfg.led_brightness >= pwm_counter ? ~SECOND_ANODE : 0xFF; 
+      ANODES_PORT = led_btnes >= pwm_counter ? ~SECOND_ANODE : 0xFF; 
       break;
   }
 
diff --git a/firmware/led.h b/firmware/led.h
index 8514291..7b61e49 100644
--- a/firmware/led.h
+++ b/firmware/led.h
@@ -12,7 +12,8 @@
 #define MINUTE_ANODE (1<<PD6)
 #define SECOND_ANODE (1<<PD7)
 
-extern volatile struct TIME led_display;
+extern volatile struct TIME_HMS led_display;
+extern volatile uint8_t led_btnes;
 
 void led_init(void);
 void led_set_btness(uint8_t btness);
diff --git a/firmware/main.c b/firmware/main.c
index 5a20855..c3936b7 100644
--- a/firmware/main.c
+++ b/firmware/main.c
@@ -1,19 +1,19 @@
-#include <avr/io.h>
 #include <avr/interrupt.h>
-#include "config.h"
+#include <avr/io.h>
 #include "keyboard.h"
 #include "ptimer.h"
+#include "config.h"
+#include "nightm.h"
 #include "time.h"
+#include "uart.h"
 #include "i2c.h"
 #include "rtc.h"
 #include "led.h"
 #include "at.h"
 
-#include "uart.h"
-
 #define I2C_BITRATE 100000UL // 100kHz
 
-char buffer[20];
+void update_time(void);
 
 int main() 
 {
@@ -28,14 +28,30 @@ int main()
 
   sei();
 
+  char uart_buf[20];
+
   while(1) 
   {
     keyboard_handle_input();
-    uart_handle_event(buffer);
+    uart_handle_event(uart_buf);
+
+    update_time();    
   }
 }
 
+void update_time(void)
+{
+  if(!(GIFR & (1<<INTF0)))
+  {
+    struct TIME_HMS curr_time = rtc_read_time();
+    led_display = curr_time;
+    nightm_handle(&curr_time);
+  }
+  
+  GIFR |= 1<<INTF0;
+}
+
 ISR(INT0_vect)
 {
-  led_display = rtc_read_time();
+
 }
\ No newline at end of file
diff --git a/firmware/nightm.c b/firmware/nightm.c
new file mode 100644
index 0000000..e27a183
--- /dev/null
+++ b/firmware/nightm.c
@@ -0,0 +1,24 @@
+#include "nightm.h"
+#include "led.h"
+
+#define TIME2INT(TIME) ((TIME).hour*60 + (TIME).minute)
+
+void nightm_config(struct NIGHTM_CFG* cfg)
+{  
+  ram_cfg.night_mode = *cfg;
+  dump_ram2eem();
+}
+
+void nightm_handle(struct TIME_HMS* curr_time)
+{  
+  if(ram_cfg.night_mode.led_btnes >= 0)
+  {
+    uint16_t current = TIME2INT(*curr_time);  
+    uint16_t begin = TIME2INT(ram_cfg.night_mode.begin);
+    uint16_t end = TIME2INT(ram_cfg.night_mode.end);
+
+    led_btnes = (begin <= current && current < end)
+    ? 1<<(ram_cfg.night_mode.led_btnes)
+    : 1<<(ram_cfg.led_brightness);
+  }
+}
\ No newline at end of file
diff --git a/firmware/nightm.h b/firmware/nightm.h
new file mode 100644
index 0000000..16b157a
--- /dev/null
+++ b/firmware/nightm.h
@@ -0,0 +1,10 @@
+#ifndef __NIGHTM_H__
+#define __NIGHTM_H__
+
+#include "config.h"
+#include "time.h"
+
+void nightm_config(struct NIGHTM_CFG* cfg);
+void nightm_handle(struct TIME_HMS* curr_time);
+
+#endif
\ No newline at end of file
diff --git a/firmware/rtc.c b/firmware/rtc.c
index a993c24..8e2a7d8 100644
--- a/firmware/rtc.c
+++ b/firmware/rtc.c
@@ -22,18 +22,18 @@ void rtc_set_time_part(uint8_t part, uint8_t value)
   i2c_writebuf(RTC_I2C_ADDR, part, 1, &bcd);
 }
 
-void rtc_set_time(struct TIME* time)
+void rtc_set_time(struct TIME_HMS* time)
 {  
   uint8_t buf[] = { DEC_2_BCD(time->second), DEC_2_BCD(time->minute), DEC_2_BCD(time->hour) };
   i2c_writebuf(RTC_I2C_ADDR, SECOND, 3, buf); // SECOND is the first memory cell (0x02)
 }
 
-struct TIME rtc_read_time(void) 
+struct TIME_HMS rtc_read_time(void) 
 {
   uint8_t buffer[3];
   i2c_readbuf(RTC_I2C_ADDR, 0x02, 3, buffer);
 
-  struct TIME curr_time = {
+  struct TIME_HMS curr_time = {
     BCD_2_DEC(buffer[2]),
     BCD_2_DEC(buffer[1]),
     BCD_2_DEC(buffer[0])
diff --git a/firmware/rtc.h b/firmware/rtc.h
index 28a551c..2396d53 100644
--- a/firmware/rtc.h
+++ b/firmware/rtc.h
@@ -21,8 +21,8 @@
 
 void rtc_int0_init(void);
 void rtc_int1_init(void);
-void rtc_set_time(struct TIME* time);
+void rtc_set_time(struct TIME_HMS* time);
 void rtc_set_time_part(uint8_t part, uint8_t value);
-struct TIME rtc_read_time(void);
+struct TIME_HMS rtc_read_time(void);
 
 #endif
\ No newline at end of file
diff --git a/firmware/time.h b/firmware/time.h
index 249fff6..7795032 100644
--- a/firmware/time.h
+++ b/firmware/time.h
@@ -1,11 +1,17 @@
 #ifndef __TIME_H__
 #define __TIME_H__
 
-struct TIME 
+struct TIME_HMS 
 {
   uint8_t hour;
   uint8_t minute;
   uint8_t second;
 };
 
+struct TIME_HM
+{
+  uint8_t hour;
+  uint8_t minute;
+};
+
 #endif
\ No newline at end of file