C语言驱动之配置定时器（基于S3C2440开发板）

这是timer.c文件

#include <s3c2440.h>
#include "timer.h"
#include "irq.h"

void timer0_init(int pre, MUX_E mux, int ms, IRQHandler irq)
{
   //1. 设置预分频
   TCFG0 &= ~(0xff << 0); //249
   TCFG0 |= (pre & 0xff) << 0;

   //2. 设置固定分频
   TCFG1 &= ~(0xf << 0); //8分频
   TCFG1 |= (mux << 0);

   //3. 设置 TCNTB，计数值，根据延时来计算的
   TCNTB0 = ms * 25; //ms * 1000 / 40(us)

   //4. 设置手动更新位，把TCNTB的值写入TCNT
   TCON |= (1 << 1); //定时器0 设置手动更新

   //5. 设置自动重装载，并且清除手动更新位
   TCON |= (1 << 3); // 定时器0设置为自动重装载
   TCON &= ~(1 << 1); //清除手动重装载

   //设置好定时器超时事件
   irq_install(IRQ_TIMER0, irq);

   //6. 启动定时器0
   TCON |= (1 << 0);

}

/*
   时间计算：
       PCLK = 50M, PCLK/(precalu+1)/(2 << (mux)) = Pin 输入的频率
       输出的时间： ms 毫秒
   count = 50000 * ms / (precalu+1)/(2 << (mux))
*/

void timer_create(TIMER_T *pstConfig)
{
   unsigned short count = 50000 * pstConfig->ms / (pstConfig->precalu + 1) / (2 << (pstConfig->mux));

   //1. 设置预分频
   if(pstConfig->id == TIMER_ID0 || pstConfig->id == TIMER_ID1)
   {
       TCFG0 &= ~(0xff); //249
       TCFG0 |= (pstConfig->precalu & 0xff);
   }
   else
   {
       TCFG0 &= ~(0xff << 8); //249
       TCFG0 |= ((pstConfig->precalu & 0xff) << 8);
   }


   //2. 设置固定分频
   TCFG1 &= ~(0xf << (pstConfig->id << 2)); //8分频
   TCFG1 |= (pstConfig->mux << (pstConfig->id << 2));

   //3. 设置 TCNTB，计数值，根据延时来计算的
   switch(pstConfig->id)
   {
       case TIMER_ID0 :
           TCNTB0 = count;
       break;
       case TIMER_ID1:
           TCNTB1 = count;
       break;
       case TIMER_ID2:
           TCNTB2 = count;
       break;
       case TIMER_ID3:
           TCNTB3 = count;
       break;
       case TIMER_ID4:
           TCNTB4 = count;
       break;
   }

   //4. 设置手动更新位，把TCNTB的值写入TCNT
   if(pstConfig->id == TIMER_ID0)
   {
       TCON |= (1 << 1); //定时器0 设置手动更新

       //5. 设置自动重装载，并且清除手动更新位
       TCON |= (1 << 3); // 定时器0设置为自动重装载
       TCON &= ~(1 << 1); //清除手动重装载
   }
   else
   {
       BIT_SET(TCON, (pstConfig->id * 4 + 5));//定时器0 设置手动更新

       //5. 设置自动重装载，并且清除手动更新位
       if(pstConfig->bAutoload)
       {
           if(pstConfig->id == TIMER_ID4)
           {
               BIT_SET(TCON, 22);
           }
           else
           {
               BIT_SET(TCON, (pstConfig->id * 4 + 7));// 定时器0设置为自动重装载
           }
       }
       else
       {
           if(pstConfig->id == TIMER_ID4)
           {
               BIT_CLR(TCON, 22);
           }
           else
           {
               BIT_CLR(TCON, (pstConfig->id * 4 + 7));// 定时器0设置为自动重装载
           }
       }
       BIT_CLR(TCON, (pstConfig->id * 4 + 5)); //清除手动重装载
   }

   //设置好定时器超时事件
   irq_install((IRQ_E)(pstConfig->id + IRQ_TIMER0), pstConfig->irq);

}

void timer_start(TIMER_ID_E timer)
{
   //6. 启动定时器0
   if(timer == TIMER_ID0)
       BIT_SET(TCON, 0);
   else
       BIT_SET(TCON, (timer*4 + 4));
}

void timer_stop(TIMER_ID_E timer)
{
   if(timer == TIMER_ID0)
       BIT_CLR(TCON, 0);
   else
       BIT_CLR(TCON, (timer*4 + 4));
}

void timer_destroy(TIMER_ID_E timer)
{
timer_stop(timer);
irq_unstall((IRQ_E)(timer + IRQ_TIMER0));
}

--------------------------------------------------华丽分割线-------------------------------------------------------

这是timer.h文件

#ifndef __TIMER_H__
#define __TIMER_H__

#include "irq.h"
#include "type.h"

// 分频比
typedef enum
{
   MUX2 = 0,
   MUX4,
   MUX8,
   MUX16

}MUX_E;

// 定时器的编号ID
typedef enum
{
   TIMER_ID0,
   TIMER_ID1,
   TIMER_ID2,
   TIMER_ID3,
   TIMER_ID4,

}TIMER_ID_E;

typedef struct {

   TIMER_ID_E id;
   unsigned char precalu; //预分频
   MUX_E mux; //固定分频
   int bAutoload; //自动重装载
   unsigned short ms; //定时时间，ms
   IRQHandler irq;

}TIMER_T;

/******************************************************************

* 函数名称： timer_create

   * 功能描述：
   *       创建定时器
   * 参数说明
   *       @id：定时器的序号
*       @prescaler：预分频值
*       @mux：固定分频比
   *       @ms：定时的时间，单位(ms)
   *       @bAuto：是否自动重装载，0：非自动加载，1：自动加载
   *       @handler：中断处理函数
   * 返回值
   *    无
******************************************************************/
void timer_create(TIMER_T *pstConfig);

void timer_start(TIMER_ID_E timer);
void timer_stop(TIMER_ID_E timer);
void timer_destroy(TIMER_ID_E timer);

void timer0_init(int pre, MUX_E mux, int ms, IRQHandler irq);

#endif /*__TIMER_H__ */

C语言驱动之配置定时器（基于S3C2440开发板）

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