//Listing 1. Modyfikacja sekcji USER CODE 0
/* USER CODE BEGIN 0 */
void uart_write(UART_HandleTypeDef * handler, char * text) {
    HAL_UART_Transmit(handler, text, strlen(text), 1000);
}

void uart_write_line(UART_HandleTypeDef * handler, char * text) {
    HAL_UART_Transmit(handler, text, strlen(text), 1000);
    HAL_UART_Transmit(handler, „\r\n”, 2, 1000);
}
uart_read_line(UART_HandleTypeDef * handler, char * buffer, uint16_t buffer_size) {
    HAL_StatusTypeDef status;
    char current_char;
    uint16_t char_counter = 0;
    while (char_counter < buffer_size - 1) {
        status = HAL_UART_Receive(handler, &current_char, 1, 1);
        if (status == HAL_OK) {
            if (current_char == ‚\r’ || current_char == ‚\n’)
                if (char_counter == 0) continue; else break;
            *(buffer + char_counter++) = current_char;
        }
    }
    *(buffer + char_counter) = ‚\0’;
}
/* USER CODE END 0 */
//Listing 2. Obsługa korekcji gamma
/* USER CODE BEGIN 0 */
void set_led_brightness(TIM_HandleTypeDef * timer, uint32_t channel, double brightness) {
    int32_t value = powf(brightness, 2.2) * 49999;
    __HAL_TIM_SET_COMPARE(timer, channel, value);
}
/* USER CODE END 0 */

//Listing 3. Uruchomienie generatora PWM
/* USER CODE BEGIN 2 */
HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_1);
HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_2);
HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_3);
/* USER CODE END 2 */

//Listing 4. Odbiór danych i zmiana koloru świecenia LED
uint8_t key[1];
HAL_StatusTypeDef status = HAL_UART_Receive(&huart2, key, 1, 1);

if (status == HAL_OK) switch (key[0]) {
    case ‚q’: red += 0.01;   break;
    case ‚w’: green += 0.01; break;
    case ‚e’: blue += 0.01;  break;
    case ‚a’: red -= 0.01;   break;
    case ‚s’: green -= 0.01; break;
    case ‚d’: blue -= 0.01;  break;
}

if (red > 1)   red = 1;   if (red < 0)   red = 0;
if (green > 1) green = 1; if (green < 0) green = 0;
if (blue > 1)  blue = 1;  if (blue < 0)  blue = 0;

set_led_brightness(&htim1, TIM_CHANNEL_1, blue);
set_led_brightness(&htim1, TIM_CHANNEL_2, red);
set_led_brightness(&htim1, TIM_CHANNEL_3, green);

//Listing 5. Funkcja wywoływana przez przerwanie USART
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) {
    switch (key[0]) {
        case ‚q’: red += 0.01;   break;
        case ‚w’: green += 0.01; break;
        case ‚e’: blue += 0.01;  break;
        case ‚a’: red -= 0.01;   break;
        case ‚s’: green -= 0.01; break;
        case ‚d’: blue -= 0.01;  break;
    }
    if (red > 1)   red = 1;   if (red < 0)   red = 0;
    if (green > 1) green = 1; if (green < 0) green = 0;
    if (blue > 1)  blue = 1;  if (blue < 0)  blue = 0;
    set_led_brightness(&htim1, TIM_CHANNEL_1, blue);
    set_led_brightness(&htim1, TIM_CHANNEL_2, red);
    set_led_brightness(&htim1, TIM_CHANNEL_3, green);
    HAL_UART_Receive_IT(&huart2, key, 1);
}

//Listing 6. Zmiany w sekcji USER CODE 2
/* USER CODE BEGIN 2 */
HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_1);
HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_2);
HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_3);
HAL_UART_Receive_IT(&huart2, key, 1);
/* USER CODE END 2 */

//Listing 7. Modyfikacja sekcji USER CODE PV
/* USER CODE BEGIN PV */
/* Private variables ---...---*/
double red = 0, green = 0, blue = 0;
uint8_t key[1];
/* USER CODE END PV */