两个51单片机 一对一通信问题

李少帅

#include<reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit Led = P1^1;
void delayms(uint xms)
{
uint i,j;
for(i=xms;i>0;i--)
for(j=110;j>0;j--);
}
void send(uchar num_key)
{
SBUF = num_key;
while(!TI);
TI =0 ;
Led = !Led ;
//while(1);

}
void main()
{
TMOD = 0x20;
TH1=0xfd;
TL1 =0xfd;
TR1 =1;
SM0 =0;
SM1 =1;
EA=1;
ES=1;
while(1)
{
   delayms(2000);
send(0xaa);
}
}
为什么上方的程序的  TXD  管脚  输出的不是  四个高  电平  四个 低电平  各位兄弟姐妹   帮一下
我在做郭天祥的  51 第十一章串口通信的提高  下面贴出代码  本人注意了他们的  gnd 要相连  为什么没反应呢   开发版都是兼容  郭天祥的
/*sender*/
#include<reg52.h>
#define uchar unsigned char
#define uint unsigned int
void delayms(uint xms)
{
uint i,j;
for(i=xms;i>0;i--)
for(j=110;j>0;j--);
}
void send(uchar num_key)
{
SBUF = num_key;
while(!TI);
TI =0 ;
}
void keyscan()
{
uchar temp,num;


P3 = 0xfe;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(5);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xee:num=0;
break;
case 0xde:num=1;
break;
case 0xbe:num=3;
break;
case 0x7e:num=4;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
send(num);
}
}

P3=0xfd;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(5);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xed:num=5;
break;
case 0xdd:num=6;
break;
case 0xbd:num=7;
break;
case 0x7d:num=8;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
send(num);
}
}


P3=0xfb;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(5);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xeb:num=9;
break;
case 0xdb:num=10;
break;
case 0xbb:num=11;
break;
case 0x7b:num=12;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
send(num);
}
}


P3=0xf7;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(5);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xe7:num=13;
break;
case 0xd7:num=14;
break;
case 0xb7:num=15;
break;
case 0x77:num=16;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
send(num);
}
}
}
void main()
{
TMOD = 0x20;
TH1=0xfd;
TL1 =0xfd;
TR1 =1;
SM0 =0;
SM1 =1;
EA=1;
ES=1;
while(1)
{
keyscan();
}
}



#include<reg52.h>
#define uint unsigned int 
#define uchar unsigned char
/**receiver**/
sbit dula=P2^6;
sbit wela =P2^7;
uint i;
uchar a=5;
uchar code table[]={
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71
};
void display(uchar num) //显示数码管字符
{
P0=table[num];
dula =1;
dula =0;
}
void main()
{
P1=0xaa;
TMOD =0x20;//定时器1 的工作方式2 
TH1=0xfd;
TL1=0xfd;
TR1=1;

REN =1;  //SCON register
SM0=0;
SM1= 1;
EA=1;
ES=1;
P0=0xc0;
wela=1;
wela=0;
 

while(1);
}
void ser() interrupt 4
{
while(RI==0);
RI=0;
a=SBUF;
display(a);
}

李少帅

问题已解决  谢谢三楼了

[mw_shl_code=c,true]uchar x=4; send(x); 对于第一段代码 我修改了这个 0xaa是不行的 而且是一个变量带入这个send函数 不能是数 否则 不行 而且板子的布局 很重要 我有了一个我不熟悉的板子 应该说和我的代码 不配套吧 那个所谓的谷峰 其实在示波器的 时间轴放大之后其实是一个波形 哎 没注意 下回注意吧 [/mw_shl_code]

李少帅

[mw_shl_code=c,true]代码发的不好看 重发一下 不过上面的也将就 #include<reg52.h> #define uchar unsigned char #define uint unsigned int sbit Led = P1^1; void delayms(uint xms) { uint i,j; for(i=xms;i>0;i--) for(j=110;j>0;j--); } void send(uchar num_key) { SBUF = num_key; while(!TI); TI =0 ; Led = !Led ; //while(1); } void main() { TMOD = 0x20; TH1=0xfd; TL1 =0xfd; TR1 =1; SM0 =0; SM1 =1; EA=1; ES=1; while(1) { delayms(2000); send(0xaa); } } [/mw_shl_code]

[mw_shl_code=c,true]/*sender*/ #include<reg52.h> #define uchar unsigned char #define uint unsigned int void delayms(uint xms) { uint i,j; for(i=xms;i>0;i--) for(j=110;j>0;j--); } void send(uchar num_key) { SBUF = num_key; while(!TI); TI =0 ; } void keyscan() { uchar temp,num; P3 = 0xfe; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delayms(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xee:num=0; break; case 0xde:num=1; break; case 0xbe:num=3; break; case 0x7e:num=4; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } send(num); } } P3=0xfd; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delayms(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xed:num=5; break; case 0xdd:num=6; break; case 0xbd:num=7; break; case 0x7d:num=8; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } send(num); } } P3=0xfb; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delayms(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xeb:num=9; break; case 0xdb:num=10; break; case 0xbb:num=11; break; case 0x7b:num=12; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } send(num); } } P3=0xf7; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delayms(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xe7:num=13; break; case 0xd7:num=14; break; case 0xb7:num=15; break; case 0x77:num=16; break; } while(temp!=0xf0) { temp=P3; temp=temp&0xf0; } send(num); } } } void main() { TMOD = 0x20; TH1=0xfd; TL1 =0xfd; TR1 =1; SM0 =0; SM1 =1; EA=1; ES=1; while(1) { keyscan(); } } [/mw_shl_code]

[mw_shl_code=c,true]#include<reg52.h> #define uint unsigned int #define uchar unsigned char /**receiver**/ sbit dula=P2^6; sbit wela =P2^7; uint i; uchar a=5; uchar code table[]={ 0x3f,0x06,0x5b,0x4f, 0x66,0x6d,0x7d,0x07, 0x7f,0x6f,0x77,0x7c, 0x39,0x5e,0x79,0x71 }; void display(uchar num) //显示数码管字符 { P0=table[num]; dula =1; dula =0; } void main() { P1=0xaa; TMOD =0x20;//定时器1 的工作方式2 TH1=0xfd; TL1=0xfd; TR1=1; REN =1; //SCON register SM0=0; SM1= 1; EA=1; ES=1; P0=0xc0; wela=1; wela=0; while(1); } void ser() interrupt 4 { while(RI==0); RI=0; a=SBUF; display(a); }[/mw_shl_code]

guset_03

第一个不要去使能"ES"、“EA”,试一下，估计跑飞了，