tim4.h
#ifndef __TIM4_H__
#define __TIM4_H__
#include "stm32mp1xx_rcc.h"
#include "stm32mp1xx_gpio.h"
#include "stm32mp1xx_tim.h"
void timer4_init();#endiftim4.c
#include "tim4.h"void timer4_init()
{// 1. 设置GPIOB，TIM4的时钟使能 RCC_MP_AHB4ENSETR RCC_MP_APB1ENSETRRCC->MP_AHB4ENSETR |= (0x1 << 1);RCC->MP_APB1ENSETR |= (0x1 << 2);// 2. 设置PB6引脚为复用功能 GPIOB_MODERGPIOB->MODER &= (~(0x3 << 12));GPIOB->MODER |= (0x2 << 12);// 3. 设置PB6引脚为TIM4_CH1功能 GPIOB_AFRLGPIOB->AFRL &= (~(0xF << 24));GPIOB->AFRL |= (0x2 << 24);// 4. 设置预分频寄存器，TIM4_PSC[15:0] CK_PSC = 209MHz // 提供给TIM4的时钟源的频率是209MHzTIM4->PSC = 20900-1; // 5. 设置PWM方波的最终的周期 TIM4_ARR[15:0] 自动装载寄存器// 得到一个1000-2000Hz的方波TIM4->ARR =10000;// 5. 设置PWM方波的占空比 TIM4_CCR1[15:0] 比较寄存器TIM4->CCR1 = 7000;// 6. 设置TIM4_CH1通道为PWM1模式 // TIM4_CCMR1[16] TIM4_CCMR1[6:4] pwm模式1 = 0b0110TIM4->CCMR1 &= (~(0x1 << 16));TIM4->CCMR1 &= (~(0x7 << 4));TIM4->CCMR1 |= (0x6 << 4);// 7. 设置TIM4_CH1通道使能TIMx_CCR1预加载使能寄存器 比较寄存器使能// TIM4_CCMR1[3] = 0x1TIM4->CCMR1 |= (0x1 << 3);// 8. 设置TIM4_CH1通道输出PWM方波的极性，// TIM_CCER[3] = 0b0 TIM4_CCER[1] = 0x1 or 0x0TIM4->CCER &= (~(0x1 << 3));TIM4->CCER |= (0x1 << 1);//TIM4->CCER &= (~(0x1 << 1));// 9. 设置TIM4_CH1通道的输出使能位，输出PWM方波 // TIM4_CCER[0] = 0x1TIM4->CCER |= (0x1 << 0);// 10. 设置TIM4_CH1通道的预装载寄存器的缓冲区的使能// TIM4_CR1[7] = 0x1TIM4->CR1 |= (0x1 << 7);// 11. 设置定时器的计数方式，边沿对齐// TIM4_CR1[6:5] = 0x0TIM4->CR1 &= (~(0x3 << 5));// 12 设置定时器计数的方向，采用递减计数/递增计数 // TIM4_CR1[4] = 0x1 TIM4->CR1 |= (0x1 << 4);// 13. 使能TIM4_CH1计数器 // TIM4_CR1[0] = 0x1TIM4->CR1 |= (0x1 << 0);
}main.c
#include "tim4.h"void delay(int ms){int i,j;for(i=0;i<ms;i++){for(j=0;j<2000;j++);}}int num[10] = {0xFC,0x60,0xDA,0xF2,0x66,0xB6,0x3E,0xE0,0xFE,0xF6};int main(){timer4_init();while(1){}//保证程序不结束return 0;}
