iic.c

ucos v2.62 安装程序 附带已移植到C8051F020的UCOS源码

/************iic dirver for c8051f020 ************************
  	
			system  clock  8M 

************************************************************/
#include "C8051F020.h"
#include "IIC.h"

static  void  GetBus ( void ); 
static  void  Delay_IIC( void );
static void SendByte( unsigned char dataa );

static void Delay_IIC()
{
   unsigned char  i=10;
   while(i--);
}
static void Delay(unsigned char i)
{
    unsigned char a;
	while(i--)
	for(a=0;a<255;a++);
}
static void GetBus()
{  
   Delay(10);
   while (BUSY==1)
   {
       STO = 1;
       Delay(10);
   }
   
   SMB0CN=RELEASE_BUS_STA;
   while(SI==0);
   if (SMB0STA != 0X08)
   {
     STO = 1;
	 SI = 0;
	 return;
   }
   STA = 0;
} 

static void SendByte( unsigned char dataa )
{  
   SMB0DAT=dataa;
   SMB0CN=RELEASE_BUS_ACK;
   while(SI==0);
}                // waitting......



/*
函数：SmbRec
功能：I2C 总线综合接收函数，从从机接收多个字节的数据
参数：
slaveAddr：从机地址（7 位纯地址，不含读写位）
subAddr：从机的子地址
subMod：子地址模式，0－无子地址，1－单字节子地址，
*recPtr：保存接收到的数据
size：数据的字节数
返回：
1：接收成功
0：在接收过程中出现异常
*/
unsigned char SmbRec(unsigned char slaveAddr,
           unsigned char *subAddress,
           unsigned char subAddressType,
           unsigned char size,
           unsigned char *recPtr )
{	
   unsigned char  counter;
   Delay_IIC();
   GetBus();
   Delay_IIC();
   slaveAddr=slaveAddr<<1;//七位地址左移1位变为八位
   SendByte(slaveAddr+0 ) ;  // send slaadd  + r 使地址为读地址
   Delay_IIC();
   if(SMB0STA!=0X18)
   {
      STO = 1;
      return(0);
   }
   if(subAddressType == ONE_BYTE_SUBA)
	{
		SendByte(*subAddress);
		if(SMB0STA != 0x28)
		{
			STO = 1;
			return 0;
		}
	}
	if(subAddressType == TWO_BYTE_SUBA)
	{
		SendByte(*subAddress);
		if(SMB0STA != 0x28)
		{
			STO = 1;
			return 0;
		}
		subAddress++;
		SendByte(*subAddress);
		if(SMB0STA != 0x28)
		{
			STO = 1;
			return 0;
		}
	}
   Delay_IIC();
   SMB0CN = RELEASE_BUS_STA;	   //从新发送STA  = 1 继续获得总线
   while (SI == 0);
   if (SMB0STA !=0X10)
   {
      STA = 0;
      STO =1;
	  return 0;
	}
	STA = 0;
   Delay_IIC();
   SendByte(slaveAddr+1);		  //读地址
   Delay_IIC();
   if (SMB0STA != 0x40)
   {
      SMB0CN = GENERATE_STOP;
      return 0;
   }   
   for(counter=0;counter<(size-1);counter++)
   {
      SMB0CN=RELEASE_BUS_ACK;                              //  set   ACK
      while (SI==0);
      if (SMB0STA!=0X50)
      {
         SMB0CN=GENERATE_STOP;
         return(0);
      }
      *recPtr=SMB0DAT;
      recPtr++;
   }
   SMB0CN=RELEASE_BUS_NACK;                                //  set     NACK
   while(SI==0);          // receive the last byte data
   *recPtr=SMB0DAT;	
   SMB0CN=GENERATE_STOP;
   Delay_IIC();
   return(1);
}
/*
函数：SmbSend
功能：I2C 总线综合发送函数，从主机发送多个字节的数据
参数：
slaveAddr：从机地址（7位纯地址，不含读写位）
subAddr：从机的子地址
subMod：子地址模式，0－无子地址，1－单字节子地址，
*recPtr：发送的字节
size：数据的字节数
返回：
0：接收成功
1：在接收过程中出现异常
*/

unsigned char SmbSend (unsigned char slaveAddr, unsigned char *subAddress, unsigned char subAddressType, unsigned char size, unsigned char *sendPtr) 
{
   unsigned char  counter;		
   GetBus();
   Delay_IIC();
   slaveAddr=slaveAddr<<1;
   SendByte(slaveAddr+0);//写信号时地址加零
   if(SMB0STA!=0X18)
   {
      STO=1;
      SI = 0;
      return(0);
   }
   if(subAddressType == ONE_BYTE_SUBA)
	{
		SendByte(*subAddress);
		if(SMB0STA != 0x28)
		{
			STO = 1;
			return 0;
		}
	}
	if(subAddressType == TWO_BYTE_SUBA)
	{
		SendByte(*subAddress);
		if(SMB0STA != 0x28)
		{
			STO = 0;
			return 0;
		}
		subAddress++;
		SendByte(*subAddress);
		if(SMB0STA != 0x28)
		{
			STO = 1;
			return 0;
		}
	}
    for(counter=0;counter<size; counter++)
    {
       SendByte ( *sendPtr );
       if( SMB0STA!=0X28 )
       {
          STO=1;
          SI = 0;
          return(0);
       }
       sendPtr++;
    }
       SMB0CN=GENERATE_STOP;
	   Delay_IIC();              // stop the bus 
       return(1);
 } // end SmbSend