【请教】局部变量在读完串口数据以后改变了。

发布于 2012-11-26 10:36:15 浏览：2587 订阅该版

代码： 
```rt_kprintf("
 1: %s strlen(ucDataBuf)=%d 
", (const char*) ucDataBuf,strlen(ucDataBuf));

rt_kprintf("
 1.1: %s strlen(ucDataBuf)=%d 
", (const char*) ucDataBuf,strlen(ucDataBuf));

ucRevSize= rt_device_read(&uart2_device, 0, ucRevBuf, 100);
ucRevBuf[ucRevSize]=0;
rt_kprintf(ucRevBuf);

rt_kprintf("
 2: %s strlen(ucDataBuf)=%d 
", (const char*) ucDataBuf,strlen(ucDataBuf));
```

打印： 
                                                                                                         
  clear ucdatabuf          //清空ucDataBuf 的长度，只有这里执行过清空长度的操作。                                                                                                    
H1:9.9;T1:19.2; ucTotalNumber=15                                                                                                    
                                                                                                                                    
 DEBUG T6615:CMD_STATUS resp ! ucNumOfRec=4                                                                                         
ff-fa-1-0-0                                                                                                                         
ff-fa-2-1-94                                                                                                                        
                                                                                                                                    
 DEBUG T6615:The PPM of C02 is 404                                                                                                  
H1:9.9;T1:19.2;C1:404; ucTotalNumber=22                                                                                             
H1:9.9;T1:19.2;C1:404; ucTotalNumber=22                                                                                             
H1:9.9;T1:19.2;C1:404; ucTotalNumber=22                                                                                             
H1:9.9;T1:19.2;C1:404;J1:0; ucTotalNumber=27                                                                                        
//从这里开始对应上面的代码                                                                                                                                    
 1: H1:9.9;T1:19.2;C1:404;J1:0; strlen(ucDataBuf)=27                                                                                
                                                                                                                                    
                                                                                                                                    
 1.1: H1:9.9;T1:19.2;C1:404;J1:0; strlen(ucDataBuf)=27             //现在还都正常                                                                  
ut:9;light:65535;ctrLine:0;                                                                                                         
ulindex:5296;RstCout:9;light:65535;ctrLine:0;                                                                                       
ulindex:5297;RstCout:9;l                                                //从UART2读取的数据                                                            
 2:  strlen(ucDataBuf)=0       // 读完串口UART2以后 ucDataBuf的长度就变成0 了。以