菜农NUC100学习笔记4(从无败绩的I2C主控模式)

 

#include "main.h"

#ifndef __NUC1xxI2c_H__

#define __NUC1xxI2c_H__

#ifdef __cplusplus

 extern "C" {

#endif 

class I2cObj;

class I2cObj {//I2C类

public://构造函数

    I2cObj(unsigned int I2CAddress = 0xa0);//默认通用EEPROM地址

private://私有方法

    inline void I2cInit(void);//I2C接口初始化

    inline void Open(void);//打开I2C接口

    inline void Start(void);//复位I2C

    inline void REStart(void);//重复位I2C

 inline void Wait(void);//超时等待

 inline void Exit(void);//出错退出

    inline void Stop(void);//成功结束

public://公有方法及属性

 static void Exec(void);//I2C中断回调函数(方法)

 unsigned char ReadByte(unsigned int, unsigned char &);//读字节函数(方法)

 unsigned char WriteByte(unsigned int, unsigned char);//写字节函数(方法)

 unsigned char ReadBuffer(unsigned int, unsigned char *, unsigned int);//读块函数(方法)

 unsigned char WriteBuffer(unsigned int, unsigned char *, unsigned int);//写块函数(方法)

 void SetAddress(unsigned int I2CAddress);//公有只写方法(属性)

 void WriteWait(void);//EEPROM写入等待函数(方法)

 unsigned int GetState(void);//公有只读方法(属性)

 void SetSystickCount(void);//公有只写方法(属性)

private://私有属性

 volatile bool Busy;//忙属性

 volatile unsigned int State;//私有属性

 volatile unsigned int SystickCount;//私有属性

 volatile unsigned int Count;//私有属性 

 volatile unsigned int MainCount, SubCount;//主从计数

 volatile unsigned int SubAddr;//私有属性

 volatile unsigned char MainComm, SubComm;//主从通讯命令

 volatile unsigned char TxBuffer[16], RxBuffer[16];//接收数据缓冲区

public://公有属性

};

#ifdef __cplusplus

}

#endif

#endif//__NUC1xxI2c_H__

 

#include "i2c.h"

I2cObj::I2cObj (unsigned int I2CAddress)

{

 SubAddr = I2CAddress;

    I2cInit();

}

void I2cObj::I2cInit(void)

{

 Open(); 

 for (int i = 0; i < sizeof(TxBuffer); i ++) {

  TxBuffer[i] = 0;

  RxBuffer[i] = 0;

 }

 Exit();//通讯失败

}

void I2cObj::Open(void)

{

   SYSs.GPAMFP.Regs |= (1 << GCR_GPAMFP_I2C0_SDA)//PA.8 Pin功能选择I2C0_SDA 

                  |  (1 << GCR_GPAMFP_I2C0_SCL);//PA.9 Pin功能选择I2C0_SCL

 SYSCLKs.APBCLK.Bits.I2C0_EN = 1;

 SYSs.IPRSTC2.Bits.I2C0_RST = 1;

 SYSs.IPRSTC2.Bits.I2C0_RST = 0; 

 I2C0s.CLK.Regs = ((DrvSYS_GetHCLKFreq()*10)/(50000 * 4) + 5) / 10 - 1;

 I2C0s.CON.Regs &= ~((1 << I2C_CON_STA)

                 |   (1 << I2C_CON_STO)

                 |   (1 << I2C_CON_AA));

 I2C0s.CON.Regs |= (1 << I2C_CON_EI)

                 | (1 << I2C_CON_ENSI)

        | (1 << I2C_CON_SI);

 comIRQ_InstallCallbackFn(I2C0_IRQn, &I2cObj::Exec);//安装I2C回调函数,并打开I2C中断

// comIRQ_InstallCallbackFn(I2C0_IRQn, &I2c.Exec);//安装I2C回调函数,并打开I2C中断

}

unsigned int I2cObj::GetState(void)

{

 return State;

}

void I2cObj::SetSystickCount(void)

{

 SystickCount ++;

}

void I2cObj::SetAddress(unsigned int I2CAddress)

{

 SubAddr = I2CAddress;

}

void I2cObj::Start(void)

{

 Busy = true;

   State = I2C_START;//主机准备发送启始位

   Count = 0;//发送数据个数

 SystickCount = 0;//清除节拍计数器

 I2C0s.CON.Regs &= ~((1 << I2C_CON_STO)

                 |   (1 << I2C_CON_AA));

 I2C0s.CON.Regs |= (1 << I2C_CON_EI)

                 | (1 << I2C_CON_ENSI)

        | (1 << I2C_CON_SI);

 I2C0s.CON.Bits.STA = 1;

 Wait(); 

}

void I2cObj::REStart(void)

{

 Busy = true;

   State = I2C_REP_START;//主机准备发送启始位

   Count = 0;//发送数据个数

 I2C0s.CON.Regs |=  (1 << I2C_CON_STA) | (1 << I2C_CON_SI);

}

void I2cObj::Stop(void)

{

 Busy = false;

 State = I2C_BUS_OK;//通讯成功

 I2C0s.CON.Regs |= (1 << I2C_CON_STO) | (1 << I2C_CON_SI);

}

void I2cObj::Exit(void)

{

 Busy = false;

 State = I2C_BUS_ERROR;//通讯失败

  I2C0s.CON.Bits.SI = 1;//清除中断标志

}

void I2cObj::Wait(void)

{

 SystickCount = 0;//清除节拍计数器

 while (Busy && SystickCount < 10);//100mS超时

}

void I2cObj::WriteWait(void)

{

 SystickCount = 0;//清除节拍计数器

 while (SystickCount < 10);//延时100mS等待写入完成

}

//I2C回调函数(静态成员函数)

void I2cObj::Exec(void)

{

  switch(I2C0s.STATUS.Regs & 0xf8) {

    case I2C_START://主机收到自己发送的开始信号

        if (I2c.State == I2C_START) {//本次中断应该接收TW_START信号

          I2C0s.DATA.Regs = I2c.SubAddr & 0xfe;//发送子机地址(写)

          I2C0s.CON.Bits.STA = 0;//此位必须清除，否则死机

     I2C0s.CON.Bits.SI = 1;//清除中断标志

    I2c.State = I2C_MT_SLA_ACK;//Status下次I2C_MT_SLA_ACK

     }

     else I2c.Exit();//通讯失败

        break;

 case I2C_REP_START://主机收到自己发送的重新开始信号

        if (I2c.State == I2C_REP_START) {//本次中断应该接收TW_RESTART信号

          I2C0s.DATA.Regs = I2c.SubAddr | 0x01;//发送子机地址(读)

       I2c.State = I2C_MR_SLA_ACK;//Status下次I2C_MR_SLA_ACK

    I2C0s.CON.Bits.STA = 0;//此位必须清除，否则读不出数据

    I2C0s.CON.Regs |= (1 << I2C_CON_SI) | (1 << I2C_CON_AA);

     }

     else I2c.Exit();//通讯失败

        break;

 case I2C_MT_SLA_ACK://主发机接收到从机的地址应答信号后发送命令

        if (I2c.State == I2C_MT_SLA_ACK) {//本次中断应该接收TW_MT_SLA_ACK信号

       I2c.State = I2C_MT_DATA_ACK;//Status下次应该收TW_MT_DATA_ACK

             I2C0s.DATA.Regs = I2c.SubComm;//发送子机命令

    I2C0s.CON.Regs |= (1 << I2C_CON_SI) | (1 << I2C_CON_AA);

     }

     else I2c.Exit();//通讯失败

        break;

 case I2C_MR_SLA_ACK://主收机接收到从机的地址应答信号

        if ((I2c.State == I2C_MR_SLA_ACK) && I2c.SubCount) {//本次中断应该接收TW_MR_SLA_ACK信号

       I2c.State = I2C_MR_DATA_ACK;//Status下次应该收TW_MR_DATA_ACK

//    I2C0s.DATA.Regs = 0XFF;//

    I2C0s.CON.Bits.SI = 1;//清除中断标志

     }

     else I2c.Exit();//通讯失败

     break;

 case I2C_MT_DATA_ACK://主收机接收到从机的数据应答信号

        if ((I2c.State == I2C_MT_DATA_ACK) && (I2c.Count < I2c.MainCount)) {//本次中断应该接收TW_MT_DATA_ACK信号

          I2C0s.DATA.Regs = I2c.TxBuffer[I2c.Count ++];//发送子机数据

       I2C0s.CON.Regs |= (1 << I2C_CON_SI) | (1 << I2C_CON_AA);

     }

     else {

          if ((I2c.State == I2C_MT_DATA_ACK) && (I2c.Count == I2c.MainCount) && (I2c.SubAddr & 1)) {//本次中断应该接收TW_MT_DATA_ACK信号

           I2c.REStart();//

    }

             else I2c.Stop();//通讯成功

     }

     break;

 case I2C_MR_DATA_ACK:

        if ((I2c.State == I2C_MR_DATA_ACK) && (I2c.Count < I2c.SubCount)) {

          I2c.RxBuffer[I2c.Count ++] = I2C0s.DATA.Regs;//接收子机数据

    if (I2c.Count < I2c.SubCount) {

         I2C0s.CON.Regs |= (1 << I2C_CON_SI) | (1 << I2C_CON_AA);//主机转入接收状态

    }

    else {

      I2C0s.CON.Bits.AA = 0;//清除ACK标志

      I2C0s.CON.Bits.SI = 1;//清除中断标志

      I2c.State = I2C_MR_DATA_NACK;//下次进入I2C_MR_DATA_NACK，接收数据准备完成

    }

     }

     else I2c.Exit();//通讯失败

     break;

 case I2C_MR_DATA_NACK://数据接收结束

        if ((I2c.State == I2C_MR_DATA_NACK) && (I2c.Count == I2c.SubCount)) {

       I2c.Stop();//通讯成功

     }

     else I2c.Exit();//通讯失败

     break;

// case I2C_MT_DATA_NACK:

//     Exit();//通讯失败

//     break;

 default:

     I2c.Exit();//通讯失败

  }

}

unsigned char I2cObj::ReadByte(unsigned int Address, unsigned char &Data)

{

 SubAddr |= 0x01;

 MainCount = 0;//发送0个数据(只读)

//本程序为通用I2C,故发送器件后一般为命令，对EEPROM来说，命令实际是EEPROM地址

 SubComm = Address;//读出地址

 SubCount = 1;//接收1个数据

 Start();//启动I2C模块

 if (State == I2C_BUS_OK) {//通讯成功

  Data = RxBuffer[0];//从接收缓冲区取出一个字节

 }

 return State;//(读出数据在RxBuffer[0]~RxBuffer[15])

}

unsigned char I2cObj::ReadBuffer(unsigned int Address, unsigned char *Data, unsigned int Cnt)

{

 SubAddr |= 0x01;

 MainCount = 0;//发送0个数据(只读)

//本程序为通用I2C,故发送器件后一般为命令，对EEPROM来说，命令实际是EEPROM地址

 SubComm = Address;//读出地址

 SubCount = (Cnt <= sizeof(RxBuffer)) ? Cnt : sizeof(RxBuffer);//接收Cnt个数据

 Start();//启动I2C模块

 if (State == I2C_BUS_OK) {//通讯成功

  for (int i = 0; i < SubCount; i ++) Data[i] = RxBuffer[i];//从接收缓冲区取出Cnt个字节

 }

 return State;//(读出数据在RxBuffer[0]~RxBuffer[15])

}

unsigned char I2cObj::WriteByte(unsigned int Address, unsigned char Data)

{

 SubAddr &= 0xfe;

 MainCount = 1;//发送1个数据

//本程序为通用I2C,故发送器件后一般为命令，对EEPROM来说，命令实际是EEPROM地址

 SubComm = Address;//写入地址

 TxBuffer[0] = Data;//写入1个数据到发送缓冲区

 SubCount = 0;//接收0个数据

 Start();//启动I2C模块

 WriteWait();//延时100mS等待写入完成

 return State;

}

unsigned char I2cObj::WriteBuffer(unsigned int Address, unsigned char *Data, unsigned int Cnt)

{

 SubAddr &= 0xfe;

 MainCount = (Cnt <= sizeof(TxBuffer)) ? Cnt : sizeof(TxBuffer);//发送Cnt个数据

//本程序为通用I2C,故发送器件后一般为命令，对EEPROM来说，命令实际是EEPROM地址

 SubComm = Address;//写入地址

 for (int i = 0; i < MainCount; i ++) TxBuffer[i] = Data[i];//写入Cnt个数据到发送缓冲区

 SubCount = 0;//接收0个数据

 Start();//启动I2C模块

 WriteWait();//延时100mS等待写入完成

 return State;

}

/*



*/