ATMEGA16读写iic(TWI)(24c02) C语言程序.doc

ATMEGA16读写iic(24c02) C语言程序 测试通过#include #include I2C.h#include 1602.h#include delay.h/*通过AVR往IIC写数据，并通过串口把数据读出显示出来*/=void UART_init(void) /UART初始化 DDRD = 0x02;PORTD = 0x00; UCSRA = 0x02; /*无倍速*/UCSRB = 0x18; /*允许接收和发送*/UCSRC = 0x06; /*8位数据,1位停止位，无校验*/UBRRH = 0x00;UBRRL = 12; /*9600*/=void USART_TXD(float data) /发送采用查询方式while( !(UCSRA & BIT(UDRE) );UDR=data;while( !(UCSRA & BIT(TXC ) );UCSRA|=BIT(TXC);void main(void) unsigned char i;/LCD_init();uart_init();/TART初始化SEI(); /全局中断使能while(1)/*I2C_Write(n,0x00);I2C_Write(c,0x01);I2C_Write(e,0x02);I2C_Write(p,0x03);I2C_Write(u,0x04);*/i=I2C_Read(0x00);/LCD_write_char(0,0,i);USART_TXD(i);i=I2C_Read(0x01);/LCD_write_data(i);USART_TXD(i);i=I2C_Read(0x02);/LCD_write_data(i);USART_TXD(i);i=I2C_Read(0x03);/LCD_write_data(i);USART_TXD(i);i=I2C_Read(0x04);/LCD_write_data(i);USART_TXD(i);/*上面上主函数部分*/#include #include delay.h/I2C 状态定义/MT 主方式传输 MR 主方式接受#define START 0x08#define RE_START 0x10#define MT_SLA_ACK 0x18#define MT_SLA_NOACK 0x20#define MT_DATA_ACK 0x28#define MT_DATA_NOACK 0x30#define MR_SLA_ACK 0x40#define MR_SLA_NOACK 0x48#define MR_DATA_ACK 0x50#define MR_DATA_NOACK 0x58 #define RD_DEVICE_ADDR 0xA1 /前4位器件固定,后三位看连线,最后1位是读写指令位#define WD_DEVICE_ADDR 0xA0/常用TWI操作(主模式写和读)#define Start() (TWCR=(1TWINT)|(1TWSTA)|(1TWEN) /启动I2C#define Stop() (TWCR=(1TWINT)|(1TWSTO)|(1TWEN) /停止I2C#define Wait() while(!(TWCR&(1TWINT); /等待中断发生#define TestAck() (TWSR&0xf8) /观察返回状态#define SetAck (TWCR|=(1TWEA) /做出ACK应答#define SetNoAck (TWCR&=(1TWEA) /做出Not Ack应答#define Twi() (TWCR=(1TWINT)|(1TWEN) /启动I2C#define Write8Bit(x) TWDR=(x);TWCR=(1TWINT)|(1TWEN); /写数据到TWDRunsigned char I2C_Write(unsigned char Wdata,unsigned char RegAddress);unsigned char I2C_Read(unsigned RegAddress);/*I2C总线写一个字节返回0:写成功返回1:写失败*/unsigned char I2C_Write(unsigned char Wdata,unsigned char RegAddress)Start(); /I2C启动Wait();if(TestAck()!=START) return 1; /ACKWrite8Bit(WD_DEVICE_ADDR); /写I2C从器件地址和写方式Wait();if(TestAck()!=MT_SLA_ACK) return 1; /ACKWrite8Bit(RegAddress); /写器件相应寄存器地址Wait();if(TestAck()!=MT_DATA_ACK) return 1; /ACKWrite8Bit(Wdata); /写数据到器件相应寄存器Wait();if(TestAck()!=MT_DATA_ACK) return 1; /ACK Stop(); /I2C停止delay_nms(10); /延时return 0;/*I2C总线读一个字节返回0:读成功返回1:读失败*/unsigned char I2C_Read(unsigned RegAddress)unsigned char temp;Start();/I2C启动Wait();if (TestAck()!=START) return 1; /ACK Write8Bit(WD_DEVICE_ADDR); /写I2C从器件地址和写方式Wait(); if (TestAck()!=MT_SLA_ACK) return 1; /ACKWrite8Bit(RegAddress); /写器件相应寄存器地址Wait();if (TestAck()!=MT_DATA_ACK) return 1;Start(); /I2C重新启动Wait();if (TestAck()!=RE_START) return 1;Write8Bit(RD_DEVICE_ADDR); /写I2C从器件地址和读方式Wait();if(TestAck()!=MR_SLA_ACK) return 1; /ACKTwi(); /启动主I2C读方式Wait();if(TestAck()!=MR_DATA_NOACK) return 1; /ACK temp=TWDR;/读取I2C接收数据Stop();/I2C停止return temp;/*以上是IIC.h头文件部分，需要对照技术文档好好研究*/*-延时函数编译器：ICC-AVR v6.31A 日期: 2005-11-24 20:29:57目标芯片 : M16时钟: 8.0000MHz作者：archeng504-*/#ifndef _delay_h#define _delay_hvoid delay_nus(unsigned int n);void delay_nms(unsigned int n);void delay_1us(void);void delay_1ms(void) ;void delay_1us(void) /1us延时函数asm(nop);void delay_nus(unsigned int n) /N us延时函数unsigned int i=0;for (i=0;in;i+)delay_1us();void delay_1ms(void) /1ms延时函数unsigned int i;for (i=0;i1140;i+);void delay_nms(unsigned int n) /N ms延时函数unsigned int i=0;for (i=0;in;i+)delay_1ms();#endif/*以上是delay.h部分，再加上IIC中自带的iom16v.h 和macr