spi_basic.c

本源码是c8051f330使用spi口在spi模式下读写SD卡

//spi接口低层输入输出接口

#include "inc.h"

sbit CS = P0^7;


void spi_sendbyte(uint8 byte)				  //发送一个字节
{

	SPI0DAT = byte;
	while(SPIF == 0);
	SPIF = 0;			          //等待SPI忙标志位清零

}

uint8 spi_recbyte(void)						  //接收一个字节
{	
	uint8 rec ;

	SPI0DAT = 0xFF;
	while(SPIF == 0);
	SPIF = 0;
	rec = SPI0DAT;


	return(rec);
	
}

void spi_cs_clr(void)						 //拉低CS
{
	CS = 0;
}

void spi_cs_set(void)						 //拉高CS
{
	CS = 1;

}