原创 lm3s6916的I2C程序,硬件的,没什么用了,留个纪念

i2c.h

#define OV9640_Device    0x3c

extern unsigned char I2cError;

void I2cBus_Init(void);
void I2cWrite(unsigned char Address,unsigned char dat);
unsigned char I2cRead(unsigned char Address);

i2c.c

#include <LM3Sxxxx.H>

#include "i2c.h"

unsigned char I2cError;

//------------------------------------------------------------------
void I2cBus_Init(void)
{
 SysCtlPeripheralEnable(SYSCTL_PERIPH_I2C0);
 SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
 GPIOPinTypeI2C(GPIO_PORTB_BASE,GPIO_PIN_2 | GPIO_PIN_3);
 I2CMasterInit(I2C0_MASTER_BASE,false);
 I2CMasterEnable(I2C0_MASTER_BASE);
}

//------------------------------------------------------------------
unsigned char I2cCheckBusyAndErr(void)
{
    unsigned int i;

 for(i=0;;i++){
  if(I2CMasterBusy(I2C0_MASTER_BASE)==false)break;
  if(i==1000)return 2;
  d1ms();
 }
 if(I2CMasterErr(I2C0_MASTER_BASE)==true)return 3;
 return 0;
}

//------------------------------------------------------------------
void I2cWrite(unsigned char Address,unsigned char dat)//写一个字节数据
{
    I2cError=0;

  I2CMasterSlaveAddrSet(I2C0_MASTER_BASE,OV9640_Device>>1,false);//写

 I2CSlaveDataPut(I2C0_MASTER_BASE,Address);
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_START);//S+DRVICE+A+ADDRESS+A
 if(I2cCheckBusyAndErr())goto WriteErr;

 I2CSlaveDataPut(I2C0_MASTER_BASE,dat);
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_FINISH);//DATA+A+S
 if(I2cCheckBusyAndErr())goto WriteErr;

 return;

WriteErr:
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_ERROR_STOP);//S
 I2cError=1;
    return;
}

//------------------------------------------------------------------
unsigned char I2cRead(unsigned char Address)//读一个字节数据
{
 unsigned int temp;

    I2cError=0;

  I2CMasterSlaveAddrSet(I2C0_MASTER_BASE,OV9640_Device>>1,false);//写
 I2CSlaveDataPut(I2C0_MASTER_BASE,Address);
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_SINGLE_SEND);//S+DRVICE+A+ADDRESS+A+P
 if(I2cCheckBusyAndErr())goto ReadErr;

 I2CMasterSlaveAddrSet(I2C0_MASTER_BASE,OV9640_Device>>1,true);//读
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_SINGLE_RECEIVE);//S+DEVICE+REV_DATA+N+P
 if(I2cCheckBusyAndErr())goto ReadErr1;
    temp="I2CMasterDataGet"(I2C0_MASTER_BASE);

 return(temp);

ReadErr:
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_ERROR_STOP);//S
 I2cError=1;
    return(0xfe);

ReadErr1:
 I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_ERROR_STOP);//S+RUN
 I2cError=1;
    return(0xfe);
}

应用:

I2cBus_Init();//初始化

i=I2cRead(0x00);读地址0x00的数据

I2cWrite(0x01,0x80);//写数据0x80到地址0x01里

这个程序只是读写一个字节的,地址码也只是一个字节的,如果要读24C256这样双字节地址那程序还要改,要想一次读写几个字节也要改程序.