LPC2103开发板I2C测试试验
工程下载地址:http://blog.chinaunix.net/u3/106835/showart_2389150.html
#include "config.h" //相关头文件
#define C02MasterAddr
#define C02SlaveAddr 0 //读写数据的起始地址
#defineLED (1 << 19)//LED IO口号
#defineLED2 (1 << 20)
#defineAA (1 << 2)//I2CONSET的各位定义
#defineSI (1 << 3)
#defineSTO (1 << 4)
#defineSTA (1 << 5)
#defineI2EN (1 << 6)
#defineWRMode 0 //写模式
#defineRDMode 1 //读模式
#definelastbyte 1 //是否为最后一个字节
uint8 I2C_buf1 = 5;
uint8 I2C_buf2 = 0;
//延时函数
void Delay(uint32 dly)
{
uint32i;
for(; dly> 0; dly--)
{
for(i = 0; i < 50000; i++);
}
}
//I2C初始化函数
void I2C_Init(uint32 Fi2c)
{
if(Fi2c> 400000)
{
Fi2c =400000;
}
PINSEL0 =(PINSEL0 & (~0xf0)) |0x50;//这里是让P02,P03选第二功能,即I2C总线
I2SCLH =(Fpclk/Fi2c + 1) / 2;//设置I2C速度为400K
I2SCLL =(Fpclk/Fi2c) / 2;
I2CONCLR =0x2c; //主发送模式对STA,AA,SI清零
I2CONSET =0x40;//使用I2C总线
// I2CONCLR =STA|AA|SI;
// I2CONSET =I2EN;
}
//I2C bus start function
void I2C_Start(void)
{
I2CONSET =STA;//set start condition
do{}while(0x08 != I2STAT);//A start condition hasbeen transmitted
I2CONCLR =STA;//clear start condition
}
//I2C bus stop function
void I2C_Stop(void)
{
I2CONSET =STO; //set STO condition
I2CONCLR =SI; //clear SI condition
}
//write byte function
void WriteByte(uint8 data)
{
I2DAT =data;// data transmitted
I2CONCLR =SI;//clear SI condition
}
//wirte I2C bus address mode is RDMode or WRMode
void WriteAddr(uint8 Mode)
{
WriteByte(C02MasterAddr + Mode);//transmite theI2C address and R/W mode
if(Mode)
{
do{}while(0x40 != I2STAT);//SLA+R has beentransmitted;ACK has been recevied
}
else
{
do{}while(0x18 != I2STAT);//SLA+W has beentransmitted;ACK has been received
}
}
//write data to I2C
void WriteData(uint8 data)
{
WriteByte(data);// data is will transmiteddata
do{}while(0x28 != I2STAT);//Data byte in I2DAThas been transmitted;ACK has been received
}
//read i2c byte
uint8 ReadByte(uint8 last)
{
if(last)
{
I2CONCLR = AA;
I2CONCLR = SI;
do{} while(0x58 != I2STAT);//data byte has beenreceived;NOT ACK has been returned
}
else
{
I2CONSET = AA;//transmited ACK
I2CONCLR = SI;
do{}while(0x50 != I2STAT);//data byte has beenreceived;ACK has been returned.
}
returnI2DAT;//return read data
}
//write data into 24c02
void WriteC02(void)
{
// uint8i;//define unsigned char i
I2C_Start();
WriteAddr(WRMode);
WriteData(C02SlaveAddr);//the data storaddress
WriteData(I2C_buf1);
I2C_Stop();
}
//read I2C data
void ReadC02(void)
{
// uint8i;
I2C_Start();
WriteAddr(WRMode);
WriteData(C02SlaveAddr);
I2C_Stop();
I2C_Start();
WriteAddr(RDMode);
I2C_buf2 =ReadByte(lastbyte);
I2C_Stop();
}
int main(void)
{
PINSEL0 =0x00000000;
PINSEL1 =0x00000000;
IODIR =LED|LED2;
IOSET =LED|LED2;
I2C_Init(400000);
WriteC02();
Delay(1000);
ReadC02();
if(I2C_buf2== I2C_buf1)
{
while(1){
IOCLR = LED;//correct LED1 light
Delay(50);
IOSET = LED;
Delay(50);
}
}
else
{
while(1)
{
IOCLR = LED2;//error LED2 light
Delay(50);
IOSET = LED2;
Delay(50);
}
}
return 0;
}