设计思路:
这个是一个STM32通过定时器产生PWM波控制小风扇的设计,首先STM32驱动ds18b20温度传感器采集环境温度,然后通过按键设置温度的阈值,不同的温度范围定时器产生的PWM波不同,相应的小风扇的转速也会不一样,温度越高,小风扇的转速越大。LCD1602显示屏显示当前温度,和设置的阈值,同时按键支持连按,也支持掉电数据保存。希望能够帮助到需要的朋友。需要参考的朋友可以在文章底部点击下载源码和原理图。
下面是main.c文件的代码
#include "stm32f10x.h"
#include "lcd.h"
#include <stdio.h>
#include "led.h"
#include "deputy.h"
#include "sys.h"
#include "delay.h"
#include "stmflash.h"
#include "ds18b20.h"
#include "LCD1602.h"
void KEY_Scan(void);
u8 KEY_scan(u8 mode);
void display_tem(void);
unsigned char Uart1_Buff[1024]; //串口1缓冲数组
unsigned char Uart1_Count=0; //串口1累加变量
u8 right=0,Tim_ms=0,state=0,s0=0,sec1=0,sec2=0,memory_flag=0;
float result=0.0000;
float table = 0.70;
int pm25Value;
float High,Low;
u8 Tem_L[20]={0};
u8 Tem_H[20]={0};
u8 showBuffer[20] = {0};
uint8_t key1_flag=0,key2_flag=0,key3_flag=0;
int main(void)
{
delay_init();
GPIO_init();
LCD1602_Init();
TIM2_Int_Init(350,7199); //10Khz,计数到5000是500ms
ds18b20_init_x();
GPIO_ResetBits(GPIOB,GPIO_Pin_10);
GPIO_SetBits(GPIOB,GPIO_Pin_11);
LCD1602_ClearScreen();
// Test_Write(0x08009100,(float)30.1);
// Test_Write(0x08009104,(float)19.2);
High=STMFLASH_ReadHalfWord(0x08009100)/16.;
Low=STMFLASH_ReadHalfWord(0x08009104)/16.;
while(1)
{
display_tem();
if(memory_flag)
{
memory_flag=0;
Test_Write(0x08009100,High*16.);//float类型扩大十倍,方便存储数据
Test_Write(0x08009104,Low*16.);
}
}
}
void display_tem(void)
{
float tem;
u16 z = 0;
z = ds18b20_read();
tem = z/16. ;
LCD1602_Show_Str(0, 0, (unsigned char *)showBuffer);
snprintf((char *)showBuffer, sizeof(showBuffer), "Cur_Tem: %2.1f", tem);
LCD1602_Write_Dat(0xDF);
LCD1602_Write_Dat(0x43);
snprintf((char *)Tem_H, sizeof(Tem_H), "H:%2.1f L:%2.1f", High,Low);
LCD1602_Show_Str(0, 1, (unsigned char *)Tem_H);
LCD1602_Write_Dat(0xDF);
LCD1602_Write_Dat(0x43);
if(tem>High)
{
TIM3_PWM_Config(9999);
}else if(tem>=Low&&tem<High)
{
TIM3_PWM_Config(4000);
}
else if(tem<Low)
{
TIM3_PWM_Config(2600);
}
}
void KEY_Scan(void)
{
if(KEY1==0)
{
state=(state+1)%3;
}while(!KEY1);
if(KEY2==0)
{
if(key2_flag==1)
{
key2_flag=0;
if(state==1)
{
if((High>0)&&(High>=Low))
High+=0.1;
else
High=Low+0.1;
}else if(state==2)
{
if((Low>0)&&(Low<=High))
Low+=0.1;
else
Low=High-0.1;
}
}
if(sec1==0)
{
if(state==1)
{
if((High>0)&&(High>=Low))
High+=0.1;
else
High=Low+0.1;
}else if(state==2)
{
if((Low>0)&&(Low<=High))
Low+=0.1;
else
Low=High-0.1;
}
}
}
else
{
sec1=7;
if(key2_flag==0)
{
key2_flag=1;
memory_flag=1;
}
}
if(KEY3==0)
{
if(key3_flag==1)
{
key3_flag=0;
if(state==1)
{
if((High>0)&&(High>=Low))
High-=0.1;
else
High=Low+0.1;
}else if(state==2)
{
if((Low>0)&&(Low<=High))
Low-=0.1;
else
Low=High-0.1;
}
}
if(sec2==0)
{
if(state==1)
{
if((High>0)&&(High>=Low))
High-=0.1;
else
High=Low+0.1;
}else if(state==2)
{
if((Low>0)&&(Low<=High))
Low-=0.1;
else
Low=High-0.1;
}
}
}
else
{
sec2=7;
if(key3_flag==0)
{
key3_flag=1;
memory_flag=1;
}
}
}
void TIM2_IRQHandler(void) //TIM2中断
{
if(TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) //检查TIM2更新中断发生与否
{
TIM_ClearITPendingBit(TIM2, TIM_IT_Update); //清除TIM2更新中断标志
Tim_ms++;
if(Tim_ms%6==0)
{
if(s0==1)
s0=0;
else
s0=1;
}
KEY_Scan();
if(state==1&&s0)
{
snprintf((char *)Tem_H, sizeof(Tem_H), "H: L:%2.1f", Low);
LCD1602_Show_Str(0, 1, (unsigned char *)Tem_H);
LCD1602_Write_Dat(0xDF);
LCD1602_Write_Dat(0x43);
}else if(state==2&&s0)
{
snprintf((char *)Tem_H, sizeof(Tem_H), "H:%2.1f L: ",High);
LCD1602_Show_Str(0, 1, (unsigned char *)Tem_H);
LCD1602_Write_Dat(0xDF);
LCD1602_Write_Dat(0x43);
}else
{
snprintf((char *)Tem_H, sizeof(Tem_H), "H:%2.1f L:%2.1f", High,Low);
LCD1602_Show_Str(0, 1, (unsigned char *)Tem_H);
LCD1602_Write_Dat(0xDF);
LCD1602_Write_Dat(0x43);
}
}
if(sec1!=0) sec1--;
if(sec2!=0) sec2--;
}
需要原理图和全部源码的朋友可以通过下面的链接下载:
源码和原理图