主要的问题可能是，清SPIF的动作应该是先读SPI0SR，再接着读SPI0DR，所以把程序改成这样就可以了：
void SPIInit(void){
SPI0BR =0b00000001;//clock divisor is 2
SPI0CR2=0b00000010; // SS is not used
SPI0CR1=0b01010000; //as master
}
char getchar_spi0(void)
{
unsigned char te;
while(!(SPI0SR_SPTEF)); /* wait until write is permissible */
SPI0DR = 0x00; /* trigger 8 SCK pulses to shift in data */
while(!(SPI0SR_SPIF)); /* wait until a byte has been shifted in */
te=SPI0SR;
te=SPI0DR; // clear the spif flag.
return te; /* return the character */
}
void putchar_spi0 (char cx)
{
char temp;
while(!(SPI0SR_SPTEF)); /* wait until write is permissible */
SPI0DR = cx; /* output the byte to the SPI */
while(!(SPI0SR_SPIF)); /* wait until write operation is complete */
temp=SPI0SR;
temp=SPI0DR; // clear the spif flag.
}
void main(void) {
char temp;
/* put your own code here */
EnableInterrupts;
SPIInit();
while(1)
{
putchar_spi0(0x0f);
temp=getchar_spi0();
}
for(;;) {} /* wait forever */
/* please make sure that you never leave this function */
}
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