#include <avr/io.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <avr/eeprom.h>
#include <avr/sleep.h>
#include <avr/wdt.h>
#include <setjmp.h>
#include <avr/interrupt.h>
#include <math.h>
#define nop asm ("nop");
/* 定义外部ram指针 */
unsigned char *eram;
int main ( void )
{
unsigned char i,j;
unsigned char *p1,*p2;
p1=( unsigned char * )0x2000;
p2=( unsigned char * )0x2001;
// unsigned char test;
/* 地址大于1100时自动访问外部ram */
MCUCR |= (1<<SRE);
// XMCRA |= (1<<SRW00);
// XMCRB |= (1<<XMM0);
*p1=10;
nop;
*p2=15;
nop;
i=*p1;
j=*p2;
nop;
while (1)
{;}
return 0;
}
为什么i和j总是读出相同的值15？
高手们指点指点
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楼主
