nuc220 I2C每次读多个字节

只看该作者 · 2014-3-11 13:41

使用NUC220的lib库IIC读写24C02. 其中rx回调函数如下:
/*---------------------------------------------------------------------------------------------------------*/
/*  I2C Rx Callback Function                                                                            */
/*---------------------------------------------------------------------------------------------------------*/
void I2C_MasterRx(uint32_t u32Status)
{
if (u32Status == 0x08)                   /* START has been transmitted and prepare SLA+W */
{
      I2C1->I2CDAT = g_u8DeviceAddr << 1;    /* Write SLA+W to Register I2CDAT */
      _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_SI);
}
else if (u32Status == 0x18)                /* SLA+W has been transmitted and ACK has been received */
{
  I2C1->I2CDAT = g_u8MemAddr;
      _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_SI);
}
else if (u32Status == 0x20)                /* SLA+W has been transmitted and NACK has been received */
{
      _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_STA_STO_SI); //发送stop停止
}
else if (u32Status == 0x28)                /* DATA has been transmitted and ACK has been received */
{
      _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_STA_SI); //再次发送start
}
else if (u32Status == 0x10)                /* Repeat START has been transmitted and prepare SLA+R */
{
      I2C1->I2CDAT = ((g_u8DeviceAddr << 1) | 0x01); /* Write SLA+R to Register I2CDAT */
      _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_SI);
}
else if (u32Status == 0x40)                /* SLA+R has been transmitted and ACK has been received */
{
      _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_SI);
}
else if (u32Status == 0x58)                /* DATA has been received and NACK has been returned */
{
  g_au8TRxData[g_u8DataLen++] = I2C1->I2CDAT;
  if (g_u8DataLen >= RTxDataSize)
  {
      g_u8EndFlag = 1;
   _I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_STO_SI); //发送stop停止
  }
  else
_I2C_SET_CONTROL_BITS(I2C1, I2C_I2CON_SI);
}
else
{
      /* TO DO */
      printf("Status 0x%x is NOT processed\n", u32Status);
}
}
这个原来是读写24LC64，每次读一个字节，现在如何改成一次可以读多个字节的. 我修改后使用以上代码发现只有第一个字节读出OK，后面全部是0xff.  24c02规格中每读一个字节，应该回复ack给24c02，但demo中没有见到任何回复ACK的地方. 请问应该如何修改此回调函数

只看该作者 · 2014-3-11 17:24

我在学校写的I2C和24LC02通信的代码，不过只发送接收了一个字节

只看该作者 · 2014-3-13 14:56

曾经做个一个项目，也是一直头疼这个问题，后来发现，一次读完所有数据再检查就OK

只看该作者 · 2014-3-14 14:21

demo只做了针对一个字节的读取，下面是我的连续读取的code，主要问题在于应答的设定，这个在技术参考手册里面有提到，可以自己去看看
/*---------------------------------------------------------------------------------------------------------*/
/*  I2C0 (Master) Rx Callback Function                                                                   */
/*---------------------------------------------------------------------------------------------------------*/
void I2C0_Callback_Rx(uint32_t status)
{
if (status == 0x08)                   /* START has been transmitted and prepare SLA+W */
{
      DrvI2C_WriteData(I2C_PORT0, Device_Addr<<1);
      DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 0);
}
else if (status == 0x18)             /* SLA+W has been transmitted and ACK has been received */
{
      DrvI2C_WriteData(I2C_PORT0, Tx_Data[0]);
      DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 0);
}
else if (status == 0x20)             /* SLA+W has been transmitted and NACK has been received */
{
      DrvI2C_Ctrl(I2C_PORT0, 1, 1, 1, 0);
}
else if (status == 0x28)             /* DATA has been transmitted and ACK has been received */
{
      DrvI2C_Ctrl(I2C_PORT0, 1, 0, 1, 0);
}
else if (status == 0x10)             /* Repeat START has been transmitted and prepare SLA+R */
{
      DrvI2C_WriteData(I2C_PORT0, Device_Addr<<1 | 0x01);
      DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 0);
}
else if (status == 0x40)             /* SLA+R has been transmitted and ACK has been received */
{
      if(RxLen == 1)
            DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 0);
else
DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 1);
}
else if (status == 0x50)             /* DATA has been received and ACK has been returned */
{
      Rx_Data[DataLen++] = DrvI2C_ReadData(I2C_PORT0);
      if(DataLen < (RxLen-1))
            DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 1);
else
            DrvI2C_Ctrl(I2C_PORT0, 0, 0, 1, 0);
}
else if (status == 0x58)             /* DATA has been received and NACK has been returned */
{
      Rx_Data[DataLen] = DrvI2C_ReadData(I2C_PORT0);
      DrvI2C_Ctrl(I2C_PORT0, 0, 1, 1, 0);
      EndFlag = 1;
}
}

nuc220 I2C每次读多个字节

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