#include "spi.h"
void spi_init()
{
InitSpiaGpio();
// 不使用FIFO
SpiaRegs.SPICCR.all =0x0007; // 空闲时,CLK=1 Reset on, rising edge, 8-bit char bits
SpiaRegs.SPICTL.all =0x000E; // Enable master mode, normal phase,
// enable talk, and SPI int disabled.
SpiaRegs.SPIBRR =0x0005; //波特率 LSPCLK/(SPIBRR+1) 7.5M LSPCLK=37.5M
SpiaRegs.SPICCR.bit.SPISWRESET=1; // Relinquish SPI from Reset
SpiaRegs.SPIPRI.bit.FREE = 1; // Set so breakpoints don't disturb xmission
}
u8 SPIx_ReadWriteByte(u8 TxData)
{
u8 retry=0;
while(SpiaRegs.SPISTS.bit.BUFFULL_FLAG == 1) //等待发送区空 发送缓冲区空时 SR的bit1 为1 不空的时为0 与后的结果为0,继续等待
{
retry++;
if(retry>200)return 0;
}
SpiaRegs.SPITXBUF=(TxData|0x8000)<<8 ; //发送一个byte
retry=0;
while(SpiaRegs.SPISTS.bit.INT_FLAG != 1)
{
retry++;
if(retry>200)return 0;
}
return ((SpiaRegs.SPIRXBUF)&0x00ff); //返回收到的数据 }
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