//实验目的：熟悉SPI总线以及9346EEPROM的读写
//RBO键按下时把DATA和DATA2写入到EEPROM中以EE—ADDR为地址的单元内，
//完成后，单个数码观显示“9”做为完成标志
//RB1键按下时，读取EEPROM中以EE—ADDR为地址的单元，并送数码管显示
//硬件要求：S7、S5、S6拨码管置ON，S1第7、8位置ON。
//若使用的是ATMEL公司的93C46，必须把“WORD SIZE”跳线选择16位端。
#include<pic.h>
__CONFIG(0x1832);
//芯片配置字，看门狗关，上电延时开，掉电检测关，低压编程关，加密，4M晶体HS振荡
#define c_s RC2
#define clk RC3
#define d_i RC5
#define d0 RC4
#define ee_addr 0x5
#define nop() asm("nop")
const char ee_data_write[]={0x56,0x78};
unsigned char ee_date[4];
const char table[]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0x88,0x83,0xC6,0xA1,0x86,0x8E};
unsigned int temp;
void init();
void ee_write();
void ee_read();
void display();
void delay();
void ee_write_enable();
void spi_comm(unsigned char x);
void main()
{
init();
while(1)
{
if(!RB0)
{
ee_write();
}
if(!RB1)
{
ee_read();
while(1)
{
display();
}
}
}
}
void init()
{
OPTION=0;
ADCON1=0X07;
TRISA=0X30;
TRISB=0X03;
TRISC=0X10;
TRISD=0X00;
PORTD=0XFF;
SSPSTAT=0X80;
SSPCON=0X31;
INTCON=0X00;
PIR1=0X00;
c_s=0;
}
void ee_write()
{
int i,j;
ee_write_enable();
c_s=1;
spi_comm(0x1);
spi_comm(ee_addr|0x40);
for(i=0;i<2;i++)
{
j=ee_data_write[i];
spi_comm(j);
}
c_s=0;
nop();
nop();
c_s=1;
nop();
nop();
while(!d0);
c_s=0;
nop();
nop();
PORTD=0X90;
PORTA=0X3E;
}
void ee_read()
{
int i;
c_s=1;
nop();
nop();
spi_comm(0x01);
spi_comm(ee_addr|0x80);
for(i=0;i<2;i++)
{
spi_comm(0);
ee_date[i]=temp;
}
nop();
c_s=0;
nop();
}
void ee_write_enable()
{
c_s=1;
spi_comm(0x01);
spi_comm(0x30);
c_s=0;
nop();
nop();
}
void spi_comm(unsigned char x)
{
SSPBUF=x;
while(!SSPIF);
SSPIF=0;
temp=SSPBUF;
}
void display()
{
int i;
i=ee_date[0]&0xf0;
i=i>>4;
PORTD=table[i];
PORTA=0x37;
delay();
i=ee_date[0]&0x0f;
PORTD=table[i];
PORTA=0x3b;
delay();
i=ee_date[1]&0xf0;
i=i>>4;
PORTD=table[i];
PORTA=0x3d;
delay();
i=ee_date[1]&0x0f;
PORTD=table[i];
PORTA=0x3e;
delay();
}
void delay()
{
int i;
for(i=100;i>0;i--);
}