xram.c

C8051F040与外部存储器接口程序

#include<c8051f040.h>
#include<intrins.h>
void PORT_Init(void);
unsigned char xdata *point;
void sleep_ms(unsigned char count)
{
unsigned char ii,jj;
for(ii=0;ii<count;ii++)
{
for(jj=0;jj<250;jj++)
_nop_();
}
}
void main(){
unsigned char k,WrData,RdData;
WDTCN=0xde;
WDTCN=0xad;
PORT_Init();
P6=0x00;
P5=0x00;
WrData=0x00;
point=0x00;
for(k=0;k<0xff;k++)
{
*point=WrData;
point++;
WrData++;
}
WrData=0x00;
point=0x00;
for(k=0;k<0xfe;k++)
{
*point=P5;
RdData=*point;
WrData++;
point++;
_nop_();
}
_nop_();
}

void PORT_Init(){
SFRPAGE   = CONFIG_PAGE;
P4MDOUT   = 0xFF;
P5MDOUT   = 0xFF;
P6MDOUT   = 0xFF;
XBR2      = 0x40;
EMI0CF|=0x2c;
EMI0TC|=0x6d;
}