无法读取PIC32MX775F256H上的RE6引脚状态

如果它是一个JTAG管脚，你需要关掉它，使用dpCONBITS.JTAGEN＝0；/ /禁用JTAGregardsRoss



      以下为原文

    hi
if its a JTAG pin you need to turn it off, use
 
DDPCONbits.JTAGEN = 0; // DISABLE JTAG
 
regards
Ross

既然你也可以阅读E5，那么我猜你还没有启用以太网（它也将接管E6）尝试常规调试列表：检查芯片：检查引脚是否是焊接桥接到地面或另一个针，如果引脚根本没有焊接。是否有任何拔出需要针？你有没有用欧姆表或范围来检查针的值是多少？同样，如果你告诉我们你正在使用的是什么：它有助于微芯片的启动工具箱或你自己的设计等等。



      以下为原文

    Since you can also read E5 then I am guessing you have not enabled Ethernet (which would take over E6 too)
Try the usual debug list:

• Inspect the chip:
  
  
  
  • Check if the pin is solder-bridged to ground or another pin
    
  • Check if the pin is not soldered at all.
    
  
  
• Is there any pull up needed on the pin?
  
• Did you check with an Ohm-meter or scope what the value at the pin is?
  

Also, it helps if you tell us what HW you are working with: A starter kit for Microchip or your own design, etc

大家好。谢谢你们的宝贵的输入。我检查并仔细检查了物理引脚本身的电压。这是正确的。我试图读取引脚状态如下：TraseBITS.TrISe6＝1；//设置Re6作为输入（CAN1高速跳线比特0）如果（PoPTBITS.Re6=＝1）/ /总是读为0 C1CFGbB.Br。P＝7；上面的代码对我来说是不适用的，尽管相同的代码将完全读R5。我将第二行改为下面的方法。如果（（PosiffSuff＆App.0xFF）& 0B0100000）＝0B0100000）/ /根据PIN状态C1CFGBITS（BRP＝7）读取真/假；这是对的。一个我自己设计的板。这是一个有趣的事情与图片和GPIO -我总是有一定程度的焦虑时，分配GPIO引脚到各种董事会的职能，因为我一半期望他们给我带来麻烦。再次感谢你们的想法。



      以下为原文

    Hello guys.
 
Thank you for your valuable input. 
 
I checked and triple checked the voltage on the physical pin itself which was correct. 
 
I was trying to read the pin state as follows: 
 
TRISEbits.TRISE6 = 1; //SET RE6 AS INPUT (CAN1 SPEED JUMPER BIT 0)
 
if( PORTEbits.RE6 == 1) //ALWAYS READS AS 0
    C1CFGbits.BRP = 7;
 
The above is what would not work for me although the same code would read RE5 perfectly well.
 
I changed the second line to the following which worked. 
 
if( ( ( portebuffer & 0xFF ) & 0b01000000 ) == 0b01000000 ) //READS TRUE/FALSE DEPENDING ON THE PIN STATE
    C1CFGbits.BRP = 7;
 
This was on a board of my own design. 
 
It is a funny thing with PICs and GPIO - I always have a certain level of anxiety when assigning GPIO pins to various board functions because I half expect them to cause me trouble. 
 
Thanks again for your thoughts guys. 
 
Nik