关于at91sam7的spi通讯问题
我用at91sam7通过spi方式与max1168通讯实现AI采集，spi发送接收例程如下：写寄存器
void SPI_Write(AT91PS_SPI spi, unsigned int npcs, unsigned int data)
{
unsigned int temp=spi->SPI_RDR;
temp=data | SPI_PCS(npcs);
while ((spi->SPI_SR & AT91C_SPI_TXEMPTY) == 0);
spi->SPI_TDR =temp;
}
//从spi读出一个字节数据
unsigned short SPI_Read(AT91S_SPI *spi)
{
unsigned int i;
while ((spi->SPI_SR & AT91C_SPI_TXEMPTY) == 0);
spi->SPI_TDR = 0xffff|0xb0000;
while ((spi->SPI_SR & AT91C_SPI_RDRF) == 0);
return spi->SPI_RDR & 0xffff;
}
但是写发送寄存器 spi->SPI_TDR =temp; 执行后，spi->SPI_TDR寄存器并没有写进去，搞了很久都没搞出来，希望大家帮忙
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