ST-LINK得到COMM TIMEOUT ERROR

这解决了
 
 
当目标连接到钉床测试夹具时，原来是一个噪音问题。



以下为原文





This is solved


Turned out to be a noise problem when the target was connected to a bed of nails test jig.

我一直在遭遇同样的问题。到昨天，我一直在使用ST-Link-2，IAR的EWSTM8，Win XP。从现在开始，我有Win 7，但它没有改变任何东西。
 
我转向IAR＆amp; ST支持这个问题，但同时我还没有得到答案。
我有一些一般性的想法可能是问题的原因，并将尝试在下一个工作周检查它们。
1.当使用任何低功率模式时，调试通道存在问题，即。如果调试器试图与MCU通信，而后者处于低功耗模式，显然，你应该得到这种错误。对于调试期间，我取消了使用Active halt模式，相反，我一直在使用一个简单的循环，模拟100msec的Halt模式。但是，除了主动暂停模式之外，我还使用等待模式短时间为20-30 us，每100毫秒。所以，我怀疑有时ST-LINK在这次尝试通信时失败了。用模拟循环替换这个代码对我来说有点困难，但如果我设法做到这一点，我肯定知道这不是问题的原因。您使用任何低功耗模式吗？
我经常使用带有十几个变量的Live watch。我不确定，但在我看来，Live Watch中的变量越多，问题就越频繁发生。
 
3. SWIM引脚上是否有串联电阻？如果是这样，请将其删除，以减小值。在发现板中，ST不在SWIM通道上放置任何串联电阻。电阻器的问题是因为SWIM是非常高速的通信信道并且任何电阻都会干扰它。我们有47欧姆，下周我将尝试删除它，看看问题是否存在。
 
如果你有一些调查结果，你会非常友好地在论坛上分享它们吗？
谢谢，
E.L。



以下为原文





I've been suffering from the same problem. By yesterday, I had been using ST-Link-2, EWSTM8 of IAR, Win XP. From now on, I have Win 7, but it haven't changed anything.

I turned to both IAR & ST support with the problem, but meanwhile I haven't got an answer.
I have a few general ideas what could be a reason for the problems, and will try to check them on the next working week.
1. There is a problem with debugging channel when any of Low power modes is being used,i.e. if debugger tries to communicate with MCU, while the latter is in Low power mode, apparently, you should get this kind of error. For debugging period I canceled using of Active halt mode and, instead, I have been using a simple loop, simulating 100msec of Halt mode. However, in addition to the Active Halt mode, I use also Wait mode for short periods of 20-30 us, every 100msec. So, I suspect that sometimes ST-LINK fails when tries to communicate in this time. It's a bit difficult to me to replace this code with a simulation loop,but if I manage to do that, I will know for sure that this is not the reason for the problem. Do you use any of Low power modes ?
2. I frequently use Live watch with a dozen of variables inside. I'm not sure, but it seems to me as the more variables inside Live watch, the problem happens more frequently.  

3. Do you have any serial resistor on SWIM pin ? If so, remove it, to decrease to a smaller value. In the Discover board, ST do not put any serial resistor on the SWIM channel. The problem with resistor is as SWIM is very high speed communication channel and any resistance disturb to it. We have 47Ohm, and next week I will try to remove it and to see if the problem exists.

If you have some findings, would you be so kind as to share them here on the forum ?
Thanks,
E.L.

对不起，好像我是瞎了。你已经在这里发布了解决方案，但我还没有看到。



以下为原文





Sorry, it seems as I'm blind. You already posted here the solution, but I have not seen that.