28035的I2C阻塞问题

你好，从你这么简单描述来看，无法确定问题出到哪儿了

代码问题有很大的可能   不知你的IIC上有没有上拉电阻  

mangui zhang：

        你好。感谢你的回复。

        IIC上有上拉电阻。下面是我的初始化代码：

// Initialize I2C
I2caRegs.I2CSAR = 0x0050; // Slave address - EEPROM control code

I2caRegs.I2CPSC.all = 6; // Prescaler - need 7 - 12Mhz on module clk
I2caRegs.I2CCLKL = 10; // NOTE: must be non zero
I2caRegs.I2CCLKH = 5; // NOTE: must be non zero
//I2caRegs.I2CIER.all = 0x24; // Enable SCD & ARDY interrupts

I2caRegs.I2CMDR.all = 0x0020; // Take I2C out of reset
// Stop I2C when suspended

I2caRegs.I2CFFTX.all = 0x6000; // Enable FIFO mode and TXFIFO
I2caRegs.I2CFFRX.all = 0x2040; // Enable RXFIFO, clear RXFFINT,

然后是使用这个函数来发送：

Uint16 I2CA_WriteData(struct I2CMSG *msg)
{
Uint16 i;

if(CurrentMsgPtr->MsgStatus != I2C_MSGSTAT_RESTART)
{
// Wait until the STP bit is cleared from any previous master communication.
// Clearing of this bit by the module is delayed until after the SCD bit is
// set. If this bit is not checked prior to initiating a new message, the
// I2C could get confused.
if (I2caRegs.I2CMDR.bit.STP == 1) //停止条件位，停止才发送
{
return I2C_STP_NOT_READY_ERROR;
}
// }

// Setup slave address
I2caRegs.I2CSAR = msg->SlaveAddress;

// Check if bus busy
if (I2caRegs.I2CSTR.bit.BB == 1) //检测总线忙，返回
{
return I2C_BUS_BUSY_ERROR;
}

// Setup number of bytes to send
// MsgBuffer + Address
I2caRegs.I2CCNT = msg->NumOfBytes;

// Send start as master transmitter
//I2caRegs.I2CMDR.all = 0x6E20;

//while(I2caRegs.I2CSTR.bit.XRDY == 0){}; //等待发送数据结束
// Setup data to send
//I2caRegs.I2CDXR = msg->MemoryHighAddr;
//I2caRegs.I2CDXR = msg->MemoryLowAddr;
// for (i=0; i<msg->NumOfBytes-2; i++)
for (i=0; i<msg->NumOfBytes; i++)
{

// while(I2caRegs.I2CSTR.bit.XRDY == 0){}; //等待发送数据结束
I2caRegs.I2CDXR = *(msg->MsgBuffer+i);

}

I2caRegs.I2CMDR.all = 0x6E20;
}

return I2C_SUCCESS;
}

当我发送一个总线上没有的从地址之后，就一直跑到这段代码，把地址改回来也不行。

if (I2caRegs.I2CSTR.bit.BB == 1) //检测总线忙，返回
{
return I2C_BUS_BUSY_ERROR;
}

是不是可以手动把bus_busy位清掉？这种情况怕到时一个从设备坏了或没有响应就会导致IIC不能使用。