大家有没有觉得STM32的I2C有比较严重的问题？SR1和SR2的值经常莫名的变，还有连续读写也会有问题，这里说的连续读写不是指24cxx的页读写，而是说，我如果先读10个字节，然后发停止位，后面跟着又读10个字节，就会失败了。请有使用经验的人指点，谢谢，下面是我的读写24c256的程序，请大家帮忙分析：
/*****************************************************************************
* 函数名：read_24cxx
* 参数：读缓冲区：read_buff，读操作其始地址：read_address 读字节数量：num
* 返回：操作的结果
*
******************************************************************************/
INT8U read_24cxx(INT8U *read_buff , INT16U read_address, INT8U length)
{
INT32U i, wait_timer;
INT8U address_8bit;
if((I2C1->SR1&0x0040)!=0) i=I2C1->DR; //清除SR1里的RXNE位,这一位经常无故置位
wait_timer=0xffff;
// Send I2C1 START condition
I2C_GenerateSTART(I2C1, ENABLE);
// Test on I2C1 EV5 and clear it
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))&&(wait_timer)) wait_timer--;
if(wait_timer==0) return TIME_OUT;
wait_timer=0xffff;
// Send I2C2 slave Address for write
I2C_Send7bitAddress(I2C1, __24C_SLAVE1_ADDRESS7, I2C_Direction_Transmitter);
// Test on I2C1 EV6 and clear it
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0) return TIME_OUT;
wait_timer=0xffff;
address_8bit = (INT8U)(read_address>>8);
I2C_SendData(I2C1, address_8bit); //send the writing address.
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0) return TIME_OUT;
wait_timer=0xffff;
address_8bit = (INT8U)(read_address);
I2C_SendData(I2C1, address_8bit); //send the writing address.
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0) return TIME_OUT;
wait_timer=0xffff;
I2C_GenerateSTART(I2C1, ENABLE);
// Test on I2C1 EV5 and clear it
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))&&(wait_timer)) wait_timer--;
if(wait_timer==0) return TIME_OUT;
// Send I2C2 slave Address for write
wait_timer=0xffff;
I2C_Send7bitAddress(I2C1, __24C_SLAVE1_ADDRESS7, I2C_Direction_Receiver);
// Test on I2C1 EV6 and clear it
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0) return TIME_OUT;
for(i=0;i<length;i++)
{
wait_timer=0xffff;
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED))&&(wait_timer)) wait_timer--;
if(wait_timer==0) break;
else
{
read_buff=I2C_ReceiveData(I2C1);
}
}
// Send I2C1 STOP Condition
I2C_GenerateSTOP(I2C1, ENABLE);
if(wait_timer==0) return TIME_OUT;
else return NO_ERROR;
}
/*****************************************************************************
* 函数名：write_24cxx
* 参数：写缓冲区：write_buff，读操作其始地址：write_address 读字节数量：num(<=64)
* 返回：操作的结果
*
******************************************************************************/
INT8U write_24cxx(INT8U * write_buff, INT16U write_address, INT8U length)
{
INT32U i, wait_timer;
INT8U address_8bit;
if(length>64) return QUANTITY_OVERRUN; //写入数量超过一页(64byte)
EN_24C_WRITE; //关闭写保护
I2C_EE_WaitEepromStandbyState(); //等待E2准备好
wait_timer=0xffff;
// Send I2C1 START condition
I2C_GenerateSTART(I2C1, ENABLE);
// Test on I2C1 EV5 and clear it
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))&&(wait_timer)) wait_timer--;
if(wait_timer==0)
{
DIS_24C_WRITE; //恢复写保护
return TIME_OUT;
}
wait_timer=0xffff;
// Send I2C2 slave Address for write
I2C_Send7bitAddress(I2C1, __24C_SLAVE1_ADDRESS7, I2C_Direction_Transmitter);
// Test on I2C1 EV6 and clear it
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0)
{
DIS_24C_WRITE;
return TIME_OUT;
}
wait_timer=0xffff;
address_8bit = (INT8U)(write_address>>8);
I2C_SendData(I2C1, address_8bit); //send the writing address.
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0)
{
DIS_24C_WRITE;
return TIME_OUT;
}
wait_timer=0xffff;
address_8bit = (INT8U)(write_address);
I2C_SendData(I2C1, address_8bit); //send the writing address.
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0)
{
DIS_24C_WRITE;
return TIME_OUT;
}
for(i=0;i<length;i++)
{
wait_timer=0xffff;
I2C_SendData(I2C1, write_buff);
while((!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))&&(wait_timer)) wait_timer--;
if(wait_timer==0) break;
}
// Send I2C1 STOP Condition
I2C_GenerateSTOP(I2C1, ENABLE);
OSTimeDly(5); //延时等待器件内部写操作结束
DIS_24C_WRITE; //恢复写保护
if(wait_timer==0) return TIME_OUT;
else return NO_ERROR;
} |
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