3.合宙Air32F103_USART_TIMER

一、简介

本章目的：在上一章已实现串口的基础上，添加定时器的功能。实现串口接收帧的时间间隔标志，当超过10ms没收到串口数据时处理当前已接收到的数据。

二、从例程移植

由于已经实现了串口的例程，只需要找到定时器的相关例程即可。

找到定时器工程的例程:

ModuleDemo\TIM\TIM_Basic\USER\TIM.uvprojx

三、移植

具体的移植过程，不再介绍了，将初始化和中断配置的部分复制过来就可以了。

3.1timer.c

在timer.c中包括定时器2和3初始化，使用串口3和串口配合实现时间间隔帧标志判断，串口2定时5秒定时发送欢迎语句。

#include #include "timer.h" #include "delay.h" #include "usart.h" void TIM2_Int_Init(u16 arr,u16 psc) {        TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;        NVIC_InitTypeDef NVIC_InitStructure;        RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); //时钟使能               //定时器TIM3初始化        TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值              TIM_TimeBaseStructure.TIM_Prescaler = psc; //设置用来作为TIMx时钟频率除数的预分频值        TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim        TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式        TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位        TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE ); //使能指定的TIM3中断,允许更新中断        //中断优先级NVIC设置        NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;  //TIM2中断        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //先占优先级0级        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;  //从优先级3级        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能        NVIC_Init(&NVIC_InitStructure);  //初始化NVIC寄存器        TIM_Cmd(TIM2, ENABLE);  //使能TIMx //     TIM_Cmd(TIM2, DISABLE);  //使能TIMx    } //通用定时器3中断初始化 //这里时钟选择为APB1的2倍，而APB1为36M //arr：自动重装值。 //psc：时钟预分频数 //这里使用的是定时器3! void TIM3_Int_Init(u16 arr,u16 psc) {   TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;        NVIC_InitTypeDef NVIC_InitStructure;        RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能               //定时器TIM3初始化        TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值              TIM_TimeBaseStructure.TIM_Prescaler = psc; //设置用来作为TIMx时钟频率除数的预分频值        TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim        TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式        TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位        TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE ); //使能指定的TIM3中断,允许更新中断        //中断优先级NVIC设置        NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //先占优先级0级        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;  //从优先级3级        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能        NVIC_Init(&NVIC_InitStructure);  //初始化NVIC寄存器 //     TIM_Cmd(TIM3, ENABLE);  //使能TIMx        TIM_Cmd(TIM3, DISABLE);  //使能TIMx } //定时器2中断服务程序 void TIM2_IRQHandler(void)   //TIM2中断 {        u8 st;        st= TIM_GetFlagStatus(TIM2, TIM_FLAG_Update);            if(st==SET)        {               TIM_ClearFlag(TIM2, TIM_FLAG_Update);               printf("wuzjjj,07-11\r\n");        } } //定时器3中断服务程序 void TIM3_IRQHandler(void)   //TIM3中断 {        u8 st;        st= TIM_GetFlagStatus(TIM3, TIM_FLAG_Update);            if(st==SET)        {               TIM_ClearFlag(TIM3, TIM_FLAG_Update);               //printf("wuzjjj\r\n");               USART1_RX_STA|=1<<15;  //标记接收完成                TIM_Cmd(TIM3, DISABLE);  //关闭TIM3        } }

3.2usart.h

#ifndef __TIMER_H__ #define __TIMER_H__ #include "sys.h" void TIM2_Int_Init(u16 arr,u16 psc); void TIM3_Int_Init(u16 arr,u16 psc); #endif

3.3usart.c

usart.c中添加相关处理。每次接收到数据后，将定时器清零，将数据存到数组USART1_RX_BUF。第一次接收数据，需要使能定时器中断。

void USART1_IRQHandler(void)                     //串口1中断服务程序 {        u8 st,sbuf;        st=USART_GetITStatus(USART1, USART_IT_RXNE);        if(st==SET)  //        {               sbuf=USART1->DR; //     usart1_1_byte(sbuf);               if((USART1_RX_STA&(1<<15))==0)//接收完的一批数据,还没有被处理,则不再接收其他数据               {                      if(USART1_RX_STA                      {                             TIM_SetCounter(TIM3,0);//计数器清空                                    //计数器清空                             if(USART1_RX_STA==0)                          //使能定时器7的中断                             {                                    TIM_Cmd(TIM3,ENABLE);//使能定时器7                             }                             USART1_RX_BUF[USART1_RX_STA++]=sbuf;  //记录接收到的值                           }else                      {                             USART1_RX_STA|=1<<15;                       //强制标记接收完成                      }               }        } }

3.4main.c

main.c中包括初始化等操作。将官方例程中的CLK打印封装到CLK_Printf中。

#include #include #include #include "delay.h" #include "led.h" #include "usart.h" #include "timer.h" void CLK_Printf(void); int main(void) {        int t=0;        delay_init();                                                                        //延时初始化        uart1_init(115200);                                                      //串口1初始化        TIM3_Int_Init(10000-1,72-1);               //定时器3初始化,10ms        TIM2_Int_Init(10000-1,36000-1);         //定时器2初始化,5000ms        clear_usart1_buffer();                                           //清空串口1接受buffer               CLK_Printf();                                                                            //打印时钟频率               LED_GPIO_Init();                                                             //LED闪烁               printf("wuzjjj\r\n");                                               //打印欢迎语句        while (1)        {               if(USART1_RX_STA&0x8000)                         //收到串口数据               {                      USART1_RX_STA = USART1_RX_STA&0x7FFF;             //去掉标志位,剩下数据长度                      printf("received,%d:",USART1_RX_STA);        //发送辅助信息及收到的数据长度                      printf("%s\r\n",USART1_RX_BUF);                                //将收到的数据发回                      clear_usart1_buffer();                                                                //清空串口1接受buffer               }                             if(t%200)                                                                                   //200ms执行一次LED控制               {                      LED_Set(t/200);                                                   //LED控制命令               }               t++;                                                                                            //时间+1               delay_ms(1);                                                                       //延时1ms        } } void CLK_Printf(void) {        RCC_ClocksTypeDef clocks;        RCC_GetClocksFreq(&clocks); //获取系统时钟频率        printf("SYSCLK:%.1fMhz,HCLK:%.1fMhz,PCLK1:%.1fMhz,PCLK2:%.1fMhz,ADCCLK:%.1fMhz\r\n",               (float)clocks.SYSCLK_Frequency/1000000,(float)clocks.HCLK_Frequency/1000000,               (float)clocks.PCLK1_Frequency/1000000,(float)clocks.PCLK2_Frequency/1000000,(float)clocks.ADCCLK_Frequency/1000000); }

四、调试

4.1下载程序

按照上一章的接线图，将A9 A10接到DAP-Link虚拟串口的A2 A3上。

 

4.2调试结果

复位后，打印当前的时钟频率，并且定时发送欢迎语句。

 串口发送后将自动回复数据。

 发回的数据是在主函数中，进行处理的。

4.3控制LED

可以在处理的地方，添加对字符串的比较，对LED进行控制。

main.c

#include #include #include #include "delay.h" #include "led.h" #include "usart.h" #include "timer.h" void CLK_Printf(void); int main(void) {        delay_init();                                                                        //延时初始化        uart1_init(115200);                                                      //串口1初始化        TIM3_Int_Init(10000-1,72-1);               //定时器3初始化,10ms //     TIM2_Int_Init(10000-1,36000-1);         //定时器2初始化,5000ms        clear_usart1_buffer();                                           //清空串口1接受buffer               CLK_Printf();                                                                            //打印时钟频率               LED_GPIO_Init();                                                             //LED闪烁               printf("wuzjjj\r\n");                                               //打印欢迎语句        while (1)        {               if(USART1_RX_STA&0x8000)                         //收到串口数据               {                      if(strcmp((char*)USART1_RX_BUF,"LEDR_ON")==0)                             LEDR_ON;                      else if(strcmp((char*)USART1_RX_BUF,"LEDR_OFF")==0)                             LEDR_OFF;                      else if(strcmp((char*)USART1_RX_BUF,"LEDG_ON")==0)                             LEDG_ON;                      else if(strcmp((char*)USART1_RX_BUF,"LEDG_OFF")==0)                             LEDG_OFF;                      else if(strcmp((char*)USART1_RX_BUF,"LEDB_ON")==0)                             LEDB_ON;                      else if(strcmp((char*)USART1_RX_BUF,"LEDB_OFF")==0)                             LEDB_OFF;                      USART1_RX_STA = USART1_RX_STA&0x7FFF;             //去掉标志位,剩下数据长度                      printf("received,%d:",USART1_RX_STA);        //发送辅助信息及收到的数据长度                      printf("%s\r\n",USART1_RX_BUF);                                //将收到的数据发回                      clear_usart1_buffer();                                                                //清空串口1接受buffer               }        } } void CLK_Printf(void) {        RCC_ClocksTypeDef clocks;        RCC_GetClocksFreq(&clocks); //获取系统时钟频率        printf("SYSCLK:%.1fMhz,HCLK:%.1fMhz,PCLK1:%.1fMhz,PCLK2:%.1fMhz,ADCCLK:%.1fMhz\r\n",               (float)clocks.SYSCLK_Frequency/1000000,(float)clocks.HCLK_Frequency/1000000,               (float)clocks.PCLK1_Frequency/1000000,(float)clocks.PCLK2_Frequency/1000000,(float)clocks.ADCCLK_Frequency/1000000); }

编译后下载程序，使用串口助手发送如下命令，即可完成对LED的控制。