1、數(shù)量:I2C1與I2C2

2、時鐘： RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1 |RCC_APB1Periph_I2C2,ENABLE);

3、IO配置為開漏輸出，在輸入時亦可讀取，此處使用功能復用。

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO,ENABLE );

RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1,ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;

GPIO_Init(GPIOB, &GPIO_InitStructure);

4、IIC本身配置

I2C_InitStructure.I2C_Mode = I2C_Mode_I2C ; //配置為普通IIC模式

I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;

I2C_InitStructure.I2C_OwnAddress1 = 0x0a; //自身設備地址

I2C_InitStructure.I2C_Ack = I2C_Ack_Enable; //使能自動應答

I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;

I2C_InitStructure.I2C_ClockSpeed = 5000; //40K的速度？

I2C_Init(I2C1, &I2C_InitStructure);

I2C_Cmd(I2C1,ENABLE);

I2C_AcknowledgeConfig(I2C1, ENABLE);

5、IIC讀取一個字節(jié)：生成一個起始信號-》發(fā)送命令碼-》等待信號-》發(fā)送地址-》發(fā)送起始信號-》發(fā)送讀取命令-》接收數(shù)據(jù)-》發(fā)送發(fā)送終止信號-》讀取寄存器接收值 么一步都有應答信號，是從設備發(fā)送的一個低信號。

vu8 IIC_Read(vu8 addr)

{

vu8 dataValue;

while(I2C_GetFlagStatus(I2C1,I2C_FLAG_BUSY));

I2C_GenerateSTART(I2C1,ENABLE);//起始信號

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_MODE_SELECT));

I2C_Send7bitAddress(I2C1,ATMADDR,I2C_Direction_Transmitter);//發(fā)送設備地址+寫信號

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));//

I2C_Cmd(I2C1,ENABLE);

I2C_SendData(I2C1,addr);//發(fā)送存儲單元地址，從0開始

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_TRANSMITTED));

I2C_GenerateSTART(I2C1,ENABLE);//起始信號

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_MODE_SELECT));

I2C_Send7bitAddress(I2C1,ATMADDR,I2C_Direction_Receiver);//發(fā)送設備地址+讀信號

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));

I2C_AcknowledgeConfig(I2C1,DISABLE);

I2C_GenerateSTOP(I2C1,ENABLE);

while(!(I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_RECEIVED)));

dataValue=I2C_ReceiveData(I2C1);//讀出寄存器數(shù)據(jù)

return dataValue;

}

6、寫一個字節(jié)：產(chǎn)生起始信號-》發(fā)送設備號+指令-》發(fā)送地址-》產(chǎn)生起始信號-》讀取數(shù)據(jù)-》產(chǎn)生結(jié)束信號

void IIC_Write(vu8 addr,vu8 dataValue)

{

I2C_GenerateSTART(I2C1,ENABLE);

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_MODE_SELECT));

I2C_Send7bitAddress(I2C1,ATMADDR,I2C_Direction_Transmitter);

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));

I2C_SendData(I2C1,addr);

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_TRANSMITTED));

I2C_SendData(I2C1,dataValue);

while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_TRANSMITTED));

I2C_GenerateSTOP(I2C1,ENABLE);

}

7、AT24C02相關(guān)

2K大小：256*8bits 也就是256頁，每頁8個bits

地址從0x00開始到0xff個字節(jié)