3.5库中例程中一点疑问

只看该作者 · 2012-5-2 19:29

本帖最后由 123456wm 于 2012-5-2 19:32 编辑

 while (TxIdx < BufferSize)

{

/* Wait for SPIy Tx buffer empty */

while (SPI_I2S_GetFlagStatus(SPIy, SPI_I2S_FLAG_TXE) == RESET); 

/* Send SPIz data */

SPI_I2S_SendData(SPIz, SPIz_Buffer_Tx[TxIdx]);   //为什么不用判断SPIz的SPI_I2S_FLAG_TXE为空

/* Send SPIy data */

SPI_I2S_SendData(SPIy, SPIy_Buffer_Tx[TxIdx++]);

/* Wait for SPIz data reception */

while (SPI_I2S_GetFlagStatus(SPIz, SPI_I2S_FLAG_RXNE) == RESET);

/* Read SPIz received data */

SPIz_Buffer_Rx[RxIdx] = SPI_I2S_ReceiveData(SPIz);

/* Wait for SPIy data reception */

while (SPI_I2S_GetFlagStatus(SPIy, SPI_I2S_FLAG_RXNE) == RESET);

/* Read SPIy received data */

SPIy_Buffer_Rx[RxIdx++] = SPI_I2S_ReceiveData(SPIy);

}