diff --git a/Core/Src/main.c b/Core/Src/main.c
index 2766bad..67c7413 100644
--- a/Core/Src/main.c
+++ b/Core/Src/main.c
@@ -68,6 +68,88 @@ static void MX_ADC1_Init(void);
 /* Private user code ---------------------------------------------------------*/
 /* USER CODE BEGIN 0 */
 
+void button_init_and_test(void)
+{
+	// letting the buttons be tested
+	display_write_data_seq("Fill any bar:");
+	DISPLAY_SET_CURSOR(1, 5);
+	display_write_data_seq("[-] [-----]");
+
+	size_t pressed_elements;
+
+	uint32_t sw_button_locations[5][2] = {
+			{GPIOC, GPIO_PIN_11},
+			{GPIOA, GPIO_PIN_15},
+			{GPIOC, GPIO_PIN_9},
+			{GPIOC, GPIO_PIN_6},
+			{GPIOC, GPIO_PIN_8}
+	};
+
+	do {
+		HAL_Delay(100);
+		pressed_elements = 0;
+
+		DISPLAY_SET_CURSOR(1, 6);
+
+		if (HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_0)) {
+			pressed_elements |= 0x20;
+			display_write_data_byte('*');
+		} else {
+			display_write_data_byte('-');
+		}
+
+		DISPLAY_SET_CURSOR(1, 10);
+
+		for (size_t i = 0; i < 5; i++) {
+			pressed_elements >>= 1;
+
+			size_t input = !HAL_GPIO_ReadPin(sw_button_locations[i][0], sw_button_locations[i][1]);
+
+			if (input) {
+				pressed_elements |= 0x20;
+				display_write_data_byte('*');
+			} else {
+				display_write_data_byte('-');
+			}
+		}
+	} while (pressed_elements != 0x1 && pressed_elements != 0x3E);
+
+
+	// visual reaction to bar fill
+	GPIOD->ODR = 0x1000;
+	HAL_Delay(500);
+	GPIOD->ODR = 0x2000;
+	HAL_Delay(500);
+	GPIOD->ODR = 0x4000;
+	HAL_Delay(500);
+	GPIOD->ODR = 0x8000;
+	HAL_Delay(500);
+	GPIOD->ODR = 0x0000;
+
+	// waiting for control buttons to be released
+	while (HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_0) | !HAL_GPIO_ReadPin(GPIOC, GPIO_PIN_8));
+	HAL_Delay(500);
+
+	// switch mode for user button
+	GPIO_InitTypeDef GPIO_InitStruct = {0};
+	GPIO_InitStruct.Pin = GPIO_PIN_0;
+	GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
+	GPIO_InitStruct.Pull = GPIO_NOPULL;
+	HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
+
+	HAL_NVIC_SetPriority(EXTI0_IRQn, 0, 0);
+	HAL_NVIC_EnableIRQ(EXTI0_IRQn);
+
+	// switch mode for SW5 (alternative advancing method)
+	GPIO_InitStruct.Pin = GPIO_PIN_8;
+	GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
+	GPIO_InitStruct.Pull = GPIO_NOPULL;
+	HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
+
+	HAL_NVIC_SetPriority(EXTI9_5_IRQn, 0, 0);
+	HAL_NVIC_EnableIRQ(EXTI9_5_IRQn);
+}
+
 /* USER CODE END 0 */
 
 /**
@@ -104,85 +186,9 @@ int main(void)
 
   GPIOD->ODR = 0x1000;
   display_init();
+
   GPIOD->ODR = 0xF000;
-
-  // init showcase
-  display_write_data_seq("Fill any bar:");
-  DISPLAY_SET_CURSOR(1, 5);
-  display_write_data_seq("[-] [-----]");
-
-  size_t pressed_elements;
-
-  uint32_t sw_button_locations[5][2] = {
-		  {GPIOC, GPIO_PIN_11},
-		  {GPIOA, GPIO_PIN_15},
-		  {GPIOC, GPIO_PIN_9},
-		  {GPIOC, GPIO_PIN_6},
-		  {GPIOC, GPIO_PIN_8}
-  };
-
-  do {
-	  HAL_Delay(100);
-	  pressed_elements = 0;
-
-	  DISPLAY_SET_CURSOR(1, 6);
-
-	  if (HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_0)) {
-		  pressed_elements |= 0x20;
-		  display_write_data_byte('*');
-	  } else {
-		  display_write_data_byte('-');
-	  }
-
-	  DISPLAY_SET_CURSOR(1, 10);
-
-	  for (size_t i = 0; i < 5; i++) {
-		  pressed_elements >>= 1;
-
-		  size_t input = !HAL_GPIO_ReadPin(sw_button_locations[i][0], sw_button_locations[i][1]);
-
-		  if (input) {
-			  pressed_elements |= 0x20;
-			  display_write_data_byte('*');
-		  } else {
-			  display_write_data_byte('-');
-		  }
-	  }
-  } while (pressed_elements != 0x1 && pressed_elements != 0x3E);
-
-
-  GPIOD->ODR = 0x1000;
-  HAL_Delay(500);
-  GPIOD->ODR = 0x2000;
-  HAL_Delay(500);
-  GPIOD->ODR = 0x4000;
-  HAL_Delay(500);
-  GPIOD->ODR = 0x8000;
-  HAL_Delay(500);
-  GPIOD->ODR = 0x0000;
-  while (HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_0));
-  HAL_Delay(500);
-
-  // switch mode for user button
-  GPIO_InitTypeDef GPIO_InitStruct = {0};
-  GPIO_InitStruct.Pin = GPIO_PIN_0;
-  GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
-  GPIO_InitStruct.Pull = GPIO_NOPULL;
-  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
-
-  HAL_NVIC_SetPriority(EXTI0_IRQn, 0, 0);
-  HAL_NVIC_EnableIRQ(EXTI0_IRQn);
-
-  // switch mode for SW5 (alternative advancing method)
-  GPIO_InitStruct.Pin = GPIO_PIN_8;
-  GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
-  GPIO_InitStruct.Pull = GPIO_NOPULL;
-  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
-
-  HAL_NVIC_SetPriority(EXTI9_5_IRQn, 0, 0);
-  HAL_NVIC_EnableIRQ(EXTI9_5_IRQn);
-
-
+  button_init_and_test();
 
   /* USER CODE END 2 */