进阶——第十六届蓝桥杯嵌入式熟练度练习（开发板输出占空比和频率）

定义变量

uint16_t PA6_frq,PA7_frq;
uint16_t PA6_duty=10,PA7_duty=20;

开启定时器PWM 

 HAL_TIM_PWM_Start(&htim16,TIM_CHANNEL_1);
 HAL_TIM_PWM_Start(&htim17,TIM_CHANNEL_1);

给变量赋值

  PA6_frq=80000000/8000/TIM16->ARR+1;
  PA7_frq=80000000/4000/TIM17->ARR+1;
  TIM16->CCR1=PA6_duty;
  TIM17->CCR1=PA7_duty;

按键改变变量

uint8_t key_scan(void)
{
uint8_t key_val=0;
	if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_0)==GPIO_PIN_RESET)
	{
	key_val=1;
	}
    if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_1)==GPIO_PIN_RESET)
	{
	key_val=2;
	}
	if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_2)==GPIO_PIN_RESET)
	{
	key_val=3;
	}
    if(HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0)==GPIO_PIN_RESET)
	{
	key_val=4;
	}
return key_val;
}
void key_proc(void)
{   key_val=key_scan();
    key_down=key_val&(key_val^key_old);
	key_up=~key_val&(key_val^key_old);
	key_old=key_val;
   if(key_down==1)
   {
	  PA6_duty+=10;
	  if(PA6_duty==100) PA6_duty=10;
	   TIM16->CCR1=PA6_duty;
   }
   if(key_down==2)
   {
	   PA7_duty+=20;
	   if(PA7_duty==100) PA7_duty=20;
	   TIM17->CCR1=PA7_duty;
   }
   if(key_down==3)
   {
   }
   if(key_down==4)
   {
   }
}

LCD显示

void lcd_proc(void)
{
	sprintf(buf,"   PA6_frq:%dHZ    ",PA6_frq);
	LCD_DisplayStringLine(Line5,(uint8_t*)buf);
    sprintf(buf,"   PA7_frq:%dHZ    ",PA7_frq);
	LCD_DisplayStringLine(Line6,(uint8_t*)buf);
    sprintf(buf,"   PA6_duty:%d%%    ",PA6_duty);
	LCD_DisplayStringLine(Line7,(uint8_t*)buf);
    sprintf(buf,"   PA7_duty:%d%%   ",PA7_duty);
	LCD_DisplayStringLine(Line8,(uint8_t*)buf);

}