LPC1788的IIC使用

#ifndef __IIC0_H_

#define __IIC0_H_

#include "common.h"

#include "delay.h"

//IIC通訊過程中的指定狀態(tài)

#define STATUS_SENDSTART 0X08 //已經(jīng)發(fā)送起始條件

#define STATUS_REPEATSTART 0X10 //已經(jīng)發(fā)送重復(fù)的起始條件

#define STATUS_SENDSLAVE_ACK 0X18 //已發(fā)送從機(jī)寫地址,接收到ACK

#define STATUS_SENDSLAVE_NACK 0X20 //已發(fā)送從機(jī)寫地址,未接收到ack

#define STATUS_SENDDATA_ACK 0X28 //已發(fā)送從機(jī)寫數(shù)據(jù),并接收到ack

#define STATUS_SENDDATA_NACK 0X30 //已發(fā)送從機(jī)寫數(shù)據(jù)沒收到ack

#define STATUS_LOSS 0X38 //丟失總線仲裁

#define STATUS_READADDR_NACK 0X48 //已經(jīng)發(fā)送從機(jī)讀地址未收到ack

#define STATUS_READADDR_ACK 0X40 //已發(fā)送從機(jī)讀地址并接受到ack

#define STATUS_RECV_ACK 0X50 //已接受數(shù)據(jù)字節(jié)ack已返回

#define STATUS_RECV_NACK 0X58 //已接受數(shù)據(jù)字節(jié)nack已返回

void iic0_init(u16 div);//參數(shù)為時鐘分頻數(shù) 不得超過65535 + 65535

u8 iic0_start(void);//發(fā)送起始信號

u8 iic0_send_write_addr(u8 addr);//發(fā)送設(shè)備寫地址

u8 iic0_send_data(u8 data);//發(fā)送數(shù)據(jù)

u8 iic0_send_stop(void);//發(fā)送停止

u8 iic0_send_read_addr(u8 addr);//發(fā)送讀地址

u8 iic0_read_data(u8*value,u8 ack);//讀取數(shù)據(jù)

u8 iic0_repeat_start(void);//重新發(fā)送start

#endif

#include "iic0.h"

#define I2EN 6 //接口使能

#define STA 5 //起始標(biāo)志

#define STO 4 //停止標(biāo)志

#define SI 3 //中斷標(biāo)志

#define AA 2 //應(yīng)答標(biāo)志

#define I2ENC 6 //清除iic使能

#define STAC 5 //清除起始

#define SIC 3 //清除中斷

#define AAC 2 //清除應(yīng)答

#define STATE (LPC_I2C0->STAT & 0xf8) //IIC總線的實(shí)際狀態(tài)信息

void iic0_init(u16 div)

{

//打開時鐘,同時打開iic和gpio時鐘

LPC_SC->PCONP|=(1<<15)|(1<<7);//打開時鐘

//配置引腳功能

LPC_IOCON->P0_27=0x00;

LPC_IOCON->P0_27|=(1<<0)|(1<<8);//打開iic功能,禁止濾波器 與引腳配置相關(guān) 根據(jù)實(shí)際引腳進(jìn)行修改

LPC_IOCON->P0_28=0x00;//選擇gpio功能,禁止遲滯 不反向 正常推挽

LPC_IOCON->P0_28|=(1<<0)|(1<<8);//打開iic功能,禁止濾波器 與引腳配置相關(guān) 根據(jù)實(shí)際引腳進(jìn)行修改

LPC_I2C0->CONCLR|=(1<

LPC_I2C0->CONCLR|=(1<

LPC_I2C0->SCLH=div/2;//設(shè)置IIC時鐘

LPC_I2C0->SCLL=div/2;

LPC_I2C0->CONSET|=(1<

}

//等待指定的狀態(tài)

//失敗返回1 成功返回0

static u8 WaitResponse(u8 response)

{

u8 retry=200;

while(--retry)

{

DelayUs(1);

if(STATE==response)break;

}

if(retry)return0;

else

{

iic0_send_stop();

return1;

}

}

u8 iic0_start(void)//發(fā)送起始信號

{

LPC_I2C0->CONCLR=(1< //Start

LPC_I2C0->CONSET=(1<

returnWaitResponse(STATUS_SENDSTART);//等待起始條件發(fā)送成功

}

u8 iic0_send_write_addr(u8 addr) //發(fā)送設(shè)備寫地址

{

//dev_addr

LPC_I2C0->DAT=addr;

LPC_I2C0->CONSET=(1<

LPC_I2C0->CONCLR=(1<

returnWaitResponse(STATUS_SENDSLAVE_ACK);//等待設(shè)備ack

}

u8 iic0_send_data(u8 data) //發(fā)送數(shù)據(jù)

{

LPC_I2C0->DAT=data;

LPC_I2C0->CONSET=(1<

LPC_I2C0->CONCLR=(1<

returnWaitResponse(STATUS_SENDDATA_ACK);

}

u8 iic0_send_stop(void)//發(fā)送停止

{

LPC_I2C0->CONCLR=(1< LPC_I2C0->CONSET=(1<

LPC_I2C0->CONCLR=(1<

return0;

}

u8 iic0_send_read_addr(u8 addr)//發(fā)送讀地址

{

LPC_I2C0->DAT=addr;

LPC_I2C0->CONSET=(1<

LPC_I2C0->CONCLR=(1<

returnWaitResponse(STATUS_READADDR_ACK);

}

u8 iic0_read_data(u8*value,u8 ack)//讀取數(shù)據(jù) 1發(fā)送ack 0不發(fā)送

{

if(ack)

{

LPC_I2C0->CONSET=(1<

LPC_I2C0->CONCLR=(1<

if(WaitResponse(STATUS_RECV_ACK))return1;

}

else

{

LPC_I2C0->CONCLR=(1<

if(WaitResponse(STATUS_RECV_NACK))return1;

}

*value=LPC_I2C0->DAT;

return0;

}

u8 iic0_repeat_start(void) //重新發(fā)送start

{

LPC_I2C0->CONCLR=(1<

LPC_I2C0->CONSET=(1<

returnWaitResponse(STATUS_REPEATSTART);//等待重復(fù)start成功

}