51单片机IO模拟SPI和25lc1024通信

#include <reg51.h> #include<intrins.h>//包含_nop_()函数 //定义命令 #define READ 0x03 #define WRITE 0x02 #define WREN 0x06 #define WRDI 0x04 #define RDSR 0x05 #define WRSR 0x01 #define PE 0x42 #define SE 0xd8 #define CE 0xc7 #define RDID 0xab #define DPD 0xb9 //端口定义 sbit SCK = P1^4; sbit MOSI = P1^5; sbit MISO = P1^6; sbit CS = P1^7; //延时程序 void delay_ms(int n) { int i, j; for(i=0;i<n;++i) for(j=0;j<1000;++j); } //延时程序 void delay_ns(void) //延时>4us { _nop_();//空指令 _nop_(); _nop_(); _nop_(); } //SPI写一个byte void SPI_byte_write(const char *dat) { char tmp = *dat, i; for(i=0;i<8;++i){ SCK = 0; MOSI = (bit)(tmp >> 7); //先输出高bit tmp <<= 1; //数据左移一位 SCK = 1; //SCK为高发送bit delay_ns(); //延时防止芯片为响应 } } //SPI读一个byte void SPI_byte_read(char *dat) { char tmp = 0, i; for(i=0;i<8;++i){ SCK = 0; tmp <<= 1; //左移一位 tmp |= MISO; //接收最高位 SCK = 1;//SCK为高接收bit delay_ns(); } *dat = tmp; } //SPI写多个byte void SPI_nbyte_write(const char *addr, const char *dat, char num) { char inst_wren = WREN, inst_write = WRITE, i; CS = 0; SPI_byte_write(&inst_wren); //写使能 CS = 1; delay_ms(1); CS = 0; SPI_byte_write(&inst_write); //写指令 for(i=0;i<3;++i){ SPI_byte_write(addr + i);//写地址 } for(i=0;i<num;++i){ SPI_byte_write(dat + i);//写数据 } CS = 1; } //SPI读多个byte void SPI_nbyte_read(const char *addr, char *dat, char num) { char inst = READ, i; CS = 0; SPI_byte_write(&inst); //读指令 for(i=0;i<3;++i){ SPI_byte_write(addr + i);//写地址 } for(i=0;i<num;++i){ SPI_byte_read(dat + i);//写数据 } CS = 1; } char dat[] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f, 0x77,0x7c,0x39,0x5e,0x79,0x71};//0~F的字形码 char save[16] = {0}; const char addr[3] = {0x00, 0x00, 0x00};//读写的地址 int main(void) { int i; SPI_nbyte_write(addr, dat, 16);//写入数据 delay_ms(30); SPI_nbyte_read(addr, save, 16);//读出数据 for(i=0;i<16;i++) { P3=save[i];//数码管显示 delay_ms(60); } return 0; }