AT93C46 SPI接口EEPROM讀寫程序

//-----------------------函數(shù)聲明--------------------------------------------------------
#include"reg51.h"
#include"intrins.h"
//-----------------------管腳聲明-----www.pICavr.com-------------------------------------

sbitCS_93=P1^0;
sbitCLK_93=P1^1;
sbitDI_93=P1^2;
sbitDO_93=P1^3;
sbitVCC_93=P1^4;
#defineREAD_c0x02
#defineWRITE_c0x01
#defineERASE_c0x03
#defineEWEN_c0x00
#defineEWDS_c0x00
#defineERAL_c0x00
#defineWRAL_c0x00
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：delay
//入口參數(shù)：N
//函數(shù)功能：延時(shí)子程序，實(shí)現(xiàn)(16*N+24)us的延時(shí)
//系統(tǒng)采用11.0592MHz的時(shí)鐘時(shí),延時(shí)滿足要求,其它情況需要改動(dòng)
//--------------------------------------------------------------------------------------------------
voiddelay(unsignedintN)
{
inti;
for(i=0;i}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：SEND_1
//函數(shù)功能：送1位數(shù)據(jù)"1"
//--------------------------------------------------------------------------------------------------
voidSEND_1(void)
{
DI_93=1;
CLK_93=1;
_nop_();
CLK_93=0;
_nop_();
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：SEND_0
//函數(shù)功能：送1位數(shù)據(jù)"0"
//--------------------------------------------------------------------------------------------------
voidSEND_0(void)
{
DI_93=0;
CLK_93=1;
_nop_();
CLK_93=0;
_nop_();
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：SEND_0
//函數(shù)功能：送1位數(shù)據(jù)"0"
//--------------------------------------------------------------------------------------------------
voidstart_operation(unsignedcharoperation_code)
{
CS_93=1;
SEND_1();//起始位
if(operation_code&0x02)//操作碼
SEND_1();
else
SEND_0();
if(operation_code&0x01)
SEND_1();
else
SEND_0();
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：SEND_BYTE
//入口參數(shù)：dd，待發(fā)送的數(shù)據(jù)
//函數(shù)功能：送1BYTE數(shù)據(jù)
//--------------------------------------------------------------------------------------------------
voidSEND_BYTE(unsignedchardd)
{
unsignedchari;
for(i=0;i<8;i++)
{
if(dd>=0x80)SEND_1();
elseSEND_0();
dd=dd<<1;
}
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：RECEIVE_BYTE
//返回值：dd，待接收的數(shù)據(jù)
//函數(shù)功能：送1BYTE數(shù)據(jù)
//--------------------------------------------------------------------------------------------------
unsignedcharRECEIVE_BYTE(void)
{
unsignedchari,dd;
DO_93=1;
for(i=0;i<8;i++)
{
dd<<=1;
CLK_93=1;_nop_();
CLK_93=0;_nop_();
if(DO_93)dd|=1;
}
return(dd);
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：EWEN
//函數(shù)功能：擦/寫允許指令
//捎讜諫系綹次緩?，AT93CXX首先將處于擦/寫不允許狀態(tài)。
//故該指令必須在所有編程模式前執(zhí)行，一旦該指令執(zhí)行后，
//只要外部沒(méi)有斷電就可以對(duì)芯片進(jìn)行編程。
//--------------------------------------------------------------------------------------------------
voidEWEN(void)
{
_nop_();
CS_93=1;
start_operation(EWEN_c);
SEND_BYTE(0xC0);
CS_93=0;
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：EWDS
//函數(shù)功能：擦寫截止
//使用該指令可對(duì)寫入的數(shù)據(jù)進(jìn)行保護(hù)
//--------------------------------------------------------------------------------------------------
voidEWDS(void)
{
_nop_();
CS_93=1;
start_operation(EWDS_c);
SEND_BYTE(0x00);
CS_93=0;
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：ERAL
//函數(shù)功能：片擦
//該指令可將整個(gè)存貯器陣列置為1，其它功能與地址擦指令相同
//要求VCC=4.5Vto5.5V。
//--------------------------------------------------------------------------------------------------
voidERAL(void)
{
_nop_();
CS_93=1;
start_operation(ERAL_c);
SEND_BYTE(0x80);
CS_93=0;
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：READ_BYTE
//函數(shù)功能：從存儲(chǔ)區(qū)讀一字節(jié)數(shù)據(jù)
//--------------------------------------------------------------------------------------------------
unsignedcharREAD_BYTE(unsignedcharaddress)
{
unsignedchardat;
CS_93=CLK_93=0;
CS_93=1;
start_operation(READ_c);
SEND_BYTE(address);
dat=RECEIVE_BYTE();
CS_93=0;
return(dat);
}
//--------------------------------------------------------------------------------------------------
//函數(shù)名稱：WRITE_BYTE
//入口參數(shù)：address。dat
//返回值：1或0，表示成功寫入
//函數(shù)功能：寫一字節(jié)數(shù)據(jù)到存儲(chǔ)區(qū)
//--------------------------------------------------------------------------------------------------
bitWRITE_BYTE(unsignedcharaddress,unsignedchardat)
{
unsignedchare,time,temp=address;
e=0;
while(e<3)
{
CS_93=CLK_93=0;
CS_93=1;
EWEN();
_nop_();
CS_93=1;
_nop_();
start_operation(WRITE_c);
SEND_BYTE(address);
SEND_BYTE(dat);
CS_93=0;
_nop_();
CS_93=1;
time=0;
DO_93=1;
while(1)
{
if(DO_93==1)break;
if(time>20)break;
time++;
}
CS_93=0;
if(READ_BYTE(temp)==dat)
{
return(0);
}
e++;
}
return(1);
}