stm32 调节RGB亮度
时间: 2023-11-13 19:44:52 浏览: 44
要调节RGB LED的亮度,可以使用PWM(脉冲宽度调制)技术。下面是一个基于STM32的代码示例,可以控制RGB LED的亮度:
```c
#include "stm32f4xx.h"
#define LED_RED_PIN GPIO_Pin_0
#define LED_GREEN_PIN GPIO_Pin_1
#define LED_BLUE_PIN GPIO_Pin_2
void init_pwm(void) {
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
GPIO_InitStructure.GPIO_Pin = LED_RED_PIN | LED_GREEN_PIN | LED_BLUE_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource0, GPIO_AF_TIM2);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource1, GPIO_AF_TIM2);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_TIM2);
TIM_TimeBaseStructure.TIM_Period = 255;
TIM_TimeBaseStructure.TIM_Prescaler = 83;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OC1Init(TIM2, &TIM_OCInitStructure);
TIM_OC2Init(TIM2, &TIM_OCInitStructure);
TIM_OC3Init(TIM2, &TIM_OCInitStructure);
TIM_Cmd(TIM2, ENABLE);
}
void set_pwm(uint8_t red, uint8_t green, uint8_t blue) {
TIM2->CCR1 = red;
TIM2->CCR2 = green;
TIM2->CCR3 = blue;
}
int main(void) {
init_pwm();
while (1) {
set_pwm(0, 0, 0); // 关闭LED
delay_ms(1000);
set_pwm(255, 0, 0); // 红色
delay_ms(1000);
set_pwm(0, 255, 0); // 绿色
delay_ms(1000);
set_pwm(0, 0, 255); // 蓝色
delay_ms(1000);
set_pwm(255, 255, 255); // 白色
delay_ms(1000);
}
}
```
代码中使用了TIM2定时器来控制PWM输出,分别使用了TIM2_CH1、TIM2_CH2、TIM2_CH3输出红、绿、蓝三色,具体的亮度值通过`TIM2->CCR1`、`TIM2->CCR2`、`TIM2->CCR3`来设置。在`set_pwm()`函数中,传入三个参数,分别是红色、绿色、蓝色的亮度值,范围是0~255。以红色为例,当参数为0时,LED灯会关闭,当参数为255时,LED灯会亮度最大,其他亮度值则会呈现不同的亮度效果。