通过PWM控制LED灯光的亮度,通过按键控制实现三档亮度的切换。 实现色温的切换,通过PWM调节白光和黄光的比例。 用stm32芯片

好的，这个问题涉及到硬件和软件两个方面，我会尽可能详细地解答。

首先，需要准备的硬件：

1. STM32开发板
2. LED灯
3. 按键
4. 电阻
5. 杜邦线

接下来，我们开始编写程序。

首先，需要初始化GPIO口作为PWM输出和按键输入。以下是初始化代码：

// 初始化LED灯的PWM输出
GPIO_InitTypeDef GPIO_InitStruct;
TIM_OC_InitTypeDef sConfigOC;
TIM_HandleTypeDef htim;

htim.Instance = TIM1;
htim.Init.Prescaler = 0;
htim.Init.CounterMode = TIM_COUNTERMODE_UP;
htim.Init.Period = 1000;
htim.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
HAL_TIM_PWM_Init(&htim);

sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
HAL_TIM_PWM_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_1);

GPIO_InitStruct.Pin = LED_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF1_TIM1;
HAL_GPIO_Init(LED_GPIO_Port, &GPIO_InitStruct);

// 初始化按键输入
GPIO_InitStruct.Pin = KEY_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_PULLUP;
HAL_GPIO_Init(KEY_GPIO_Port, &GPIO_InitStruct);

接下来，需要编写控制PWM输出的函数。我们可以将它封装成一个函数，方便后面的调用。以下是函数代码：

void setPWM(uint16_t dutyCycle) {
    TIM_OC_InitTypeDef sConfigOC;
    uint32_t pulse = (1000 * dutyCycle) / 100;
    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = pulse;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    HAL_TIM_PWM_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_1);
    HAL_TIM_PWM_Start(&htim, TIM_CHANNEL_1);
}

接下来，需要编写控制LED灯亮度的代码。我们可以将三档亮度分别设置为33%、66%和100%。以下是代码：

if (HAL_GPIO_ReadPin(KEY_GPIO_Port, KEY_Pin) == GPIO_PIN_RESET) {
    if (dutyCycle == 100) {
        dutyCycle = 33;
    } else if (dutyCycle == 33) {
        dutyCycle = 66;
    } else if (dutyCycle == 66) {
        dutyCycle = 100;
    }
    setPWM(dutyCycle);
}

最后，我们需要实现色温的切换。我们可以使用两个PWM输出分别控制白光和黄光的亮度，然后通过改变两个PWM输出的占空比比例来实现色温的调节。以下是代码：

uint16_t whiteDutyCycle = 50;
uint16_t yellowDutyCycle = 50;

while (1) {
    if (HAL_GPIO_ReadPin(KEY_GPIO_Port, KEY_Pin) == GPIO_PIN_RESET) {
        if (whiteDutyCycle == 50) {
            whiteDutyCycle = 33;
            yellowDutyCycle = 66;
        } else if (whiteDutyCycle == 33) {
            whiteDutyCycle = 50;
            yellowDutyCycle = 50;
        } else if (whiteDutyCycle == 66) {
            whiteDutyCycle = 50;
            yellowDutyCycle = 33;
        }
        setPWM(whiteDutyCycle);
        setPWM2(yellowDutyCycle);
    }
}

完整代码如下：

#include "main.h"

TIM_HandleTypeDef htim;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM1_Init(void);

void setPWM(uint16_t dutyCycle) {
    TIM_OC_InitTypeDef sConfigOC;
    uint32_t pulse = (1000 * dutyCycle) / 100;
    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = pulse;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    HAL_TIM_PWM_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_1);
    HAL_TIM_PWM_Start(&htim, TIM_CHANNEL_1);
}

void setPWM2(uint16_t dutyCycle) {
    TIM_OC_InitTypeDef sConfigOC;
    uint32_t pulse = (1000 * dutyCycle) / 100;
    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = pulse;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    HAL_TIM_PWM_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_2);
    HAL_TIM_PWM_Start(&htim, TIM_CHANNEL_2);
}

int main(void) {
    HAL_Init();
    SystemClock_Config();
    MX_GPIO_Init();
    MX_TIM1_Init();

    uint16_t dutyCycle = 100;
    uint16_t whiteDutyCycle = 50;
    uint16_t yellowDutyCycle = 50;

    while (1) {
        if (HAL_GPIO_ReadPin(KEY_GPIO_Port, KEY_Pin) == GPIO_PIN_RESET) {
            if (dutyCycle == 100) {
                dutyCycle = 33;
            } else if (dutyCycle == 33) {
                dutyCycle = 66;
            } else if (dutyCycle == 66) {
                dutyCycle = 100;
            }
            setPWM(dutyCycle);
        }

        if (HAL_GPIO_ReadPin(KEY_GPIO_Port, KEY_Pin) == GPIO_PIN_RESET) {
            if (whiteDutyCycle == 50) {
                whiteDutyCycle = 33;
                yellowDutyCycle = 66;
            } else if (whiteDutyCycle == 33) {
                whiteDutyCycle = 50;
                yellowDutyCycle = 50;
            } else if (whiteDutyCycle == 66) {
                whiteDutyCycle = 50;
                yellowDutyCycle = 33;
            }
            setPWM(whiteDutyCycle);
            setPWM2(yellowDutyCycle);
        }
    }
}

void SystemClock_Config(void) {
    RCC_OscInitTypeDef RCC_OscInitStruct = {0};
    RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

    /** Initializes the RCC Oscillators according to the specified parameters
    * in the RCC_OscInitTypeDef structure.
    */
    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
    RCC_OscInitStruct.HSIState = RCC_HSI_ON;
    RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
        Error_Handler();
    }
    /** Initializes the CPU, AHB and APB buses clocks
    */
    RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
            | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK) {
        Error_Handler();
    }
}

static void MX_TIM1_Init(void) {
    TIM_MasterConfigTypeDef sMasterConfig = {0};
    TIM_OC_InitTypeDef sConfigOC = {0};

    htim.Instance = TIM1;
    htim.Init.Prescaler = 0;
    htim.Init.CounterMode = TIM_COUNTERMODE_UP;
    htim.Init.Period = 1000;
    htim.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
    HAL_TIM_PWM_Init(&htim);

    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = 0;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    HAL_TIM_PWM_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_1);
    HAL_TIM_PWM_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_2);

    sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
    sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
    HAL_TIMEx_MasterConfigSynchronization(&htim, &sMasterConfig);
}

static void MX_GPIO_Init(void) {
    GPIO_InitTypeDef GPIO_InitStruct = {0};

    __HAL_RCC_GPIOA_CLK_ENABLE()
    ;
    __HAL_RCC_GPIOB_CLK_ENABLE()
    ;

    HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_RESET);

    GPIO_InitStruct.Pin = LED_Pin;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF1_TIM1;
    HAL_GPIO_Init(LED_GPIO_Port, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = KEY_Pin;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_PULLUP;
    HAL_GPIO_Init(KEY_GPIO_Port, &GPIO_InitStruct);
}

希望这个回答能够帮到你。