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STM32 硬件I2C EEPROM命令解析

作者: 时间:2016-11-21 来源:网络 收藏
void I2C_EE_BufferWrite(u8* pBuffer, u8 WriteAddr, u16 NumByteToWrite)
{
u8 NumOfPage = 0, NumOfSingle = 0, Addr = 0, count = 0;
//写入地址是每页的第几位
Addr = WriteAddr % I2C_PageSize;
//在开始的一页要写入的个数
count = I2C_PageSize - Addr;
//要写入的页数
NumOfPage = NumByteToWrite / I2C_PageSize;
//不足一页的个数
NumOfSingle = NumByteToWrite % I2C_PageSize;
// EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
//写入地址是页的开始
if (Addr == 0)
{
//数据小于一页
if (NumOfPage == 0)
{
//写少于一页的数据
I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
}
//数据大于等于一页
else
{
while (NumOfPage--)//要写入的页数
{
//写一页的数据
I2C_EE_PageWrite(pBuffer, WriteAddr, I2C_PageSize);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
WriteAddr += I2C_PageSize;
pBuffer += I2C_PageSize;
}
//剩余数据小于一页
if (NumOfSingle!=0)
{
//写少于一页的数据
I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
}
}
}
//写入地址不是页的开始
else
{
//数据小于一页
if (NumOfPage== 0)
{
//写少于一页的数据
I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
}
//数据大于等于一页
else
{
NumByteToWrite -= count;
//重新计算要写入的页数
NumOfPage = NumByteToWrite / I2C_PageSize;
//重新计算不足一页的个数
NumOfSingle = NumByteToWrite % I2C_PageSize;
if (count != 0)
{
//将开始的空间写满一页
I2C_EE_PageWrite(pBuffer, WriteAddr, count);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
WriteAddr += count;
pBuffer += count;
}
//要写入的页数
while (NumOfPage--)
{
//写一页的数据
I2C_EE_PageWrite(pBuffer, WriteAddr, I2C_PageSize);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
WriteAddr += I2C_PageSize;
pBuffer += I2C_PageSize;
}
//剩余数据小于一页
if (NumOfSingle != 0)
{
//写少于一页的数据
I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
}
}
}
}
void I2C_EE_ByteWrite(u8* pBuffer, u8 WriteAddr)
{
//产生 I2C2传输 START条件
I2C_GenerateSTART(I2C2, ENABLE);
//通过START的产生,确定主机模式是否成功(检测EV5)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));
//发送器件地址(写)
I2C_Send7bitAddress(I2C2, EEPROM_ADDRESS, I2C_Direction_Transmitter);
//检测主机传输模式是否成功(检测EV6)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
//通过外设 I2C2发送地址
I2C_SendData(I2C2, WriteAddr);
//检测主机发送的字节是否成功(检测EV8)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
//通过外设 I2C2发送数据
I2C_SendData(I2C2, *pBuffer);
//检测主机发送的字节是否成功(检测EV8)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
//产生 I2C2传输 STOP条件
I2C_GenerateSTOP(I2C2, ENABLE);
}
void I2C_EE_PageWrite(u8* pBuffer, u8 WriteAddr, u8 NumByteToWrite)
{
//产生 I2C2传输 START条件
I2C_GenerateSTART(I2C2, ENABLE);
//通过START的产生,确定主机模式是否成功(检测EV5)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));
//发送器件地址(写)
I2C_Send7bitAddress(I2C2, EEPROM_ADDRESS, I2C_Direction_Transmitter);
//检测主机传输模式是否成功(检测EV6)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
//通过外设 I2C2发送地址
I2C_SendData(I2C2, WriteAddr);
//检测主机发送的字节是否成功(检测EV8)
while (! I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
//写数据
while (NumByteToWrite--)
{
//通过外设 I2C2发送数据
I2C_SendData(I2C2, *pBuffer);
//指针++
pBuffer++;
//检测主机发送的字节是否成功(检测EV8)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
}
//产生 I2C2 传输 STOP条件
I2C_GenerateSTOP(I2C2, ENABLE);
}
void I2C_EE_BufferRead(u8* pBuffer, u8 ReadAddr, u16 NumByteToRead)
{
//EEPROM设为待命状态
I2C_EE_WaitEepromStandbyState();
//产生 I2C2传输 START条件
I2C_GenerateSTART(I2C2, ENABLE);
//通过START的产生,确定主机模式是否成功(检测EV5)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));
//在一个单一的数据传输情况下读取数据之前禁用的ACK
if (NumByteToRead==1)
{
I2C_Acknow ledgeConfig(I2C2, DISABLE);//失能I2C2 的应答功能
}
//向指定的从 I2C设备传送地址字,选择发送方向
I2C_Send7bitAddress(I2C2, EEPROM_ADDRESS, I2C_Direction_Transmitter);
//检测主机传输模式是否成功(检测EV6)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
//使能I2C外设
I2C_Cmd(I2C2, ENABLE);
//通过外设 I2C2发送地址
I2C_SendData(I2C2, ReadAddr);
//检测主机发送的字节是否成功(检测EV8)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
//产生 I2C2 传输 START条件
I2C_GenerateSTART(I2C2, ENABLE);
//通过START的产生,确定主机模式是否成功(检测EV5)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT));
//向指定的从 I2C设备传送地址字,选择接收方向
I2C_Send7bitAddress(I2C2, EEPROM_ADDRESS, I2C_Direction_Receiver);
//检测主机接收模式是否成功(检测EV6)
while (!I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
//读取数据
while (NumByteToRead)
{
//检测主机接收的字节是否成功(检测EV8)
if (I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_RECEIVED))
{
if (NumByteToRead == 2)
{
//使能或者失能指定 I2C的应答功能
I2C_AcknowledgeConfig(I2C2, DISABLE);
}
if (NumByteToRead == 1)
{
//产生 I2C2 传输 STOP条件
I2C_GenerateSTOP(I2C2, ENABLE);
}
//返回通过 I2C2最近接收的数据
*pBuffer = I2C_ReceiveData(I2C2);
//指向下个地址
pBuffer++;
NumByteToRead--;
}
}
//使能I2C2 的应答功能
I2C_AcknowledgeConfig(I2C2, ENABLE);
}
void I2C_EE_WaitEepromStandbyState(void)
{
vu16 SR1_Tmp = 0;
do
{
//产生 I2C2传输 START条件
I2C_GenerateSTART(I2C2, ENABLE);
//读取指定的 I2C寄存器 I2C_SR1 并返回其值
SR1_Tmp = I2C_ReadRegister(I2C2, I2C_Register_SR1);
//向指定的从 I2C设备传送地址字 ,选择发送方向
I2C_Send7bitAddress(I2C2, EEPROM_ADDRESS, I2C_Direction_Transmitter);
} while (!(I2C_ReadRegister(I2C2, I2C_Register_SR1) & 0x0002));//地址发送结束
//清除 I2Cx的应答错误标志位
I2C_ClearFlag(I2C2, I2C_FLAG_AF);
}



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