Thomas Kastner thomas.kastner@marekmicro.de wrote: [snip]

Generally speaking cooler spray has saved me a lot of time finding the cause of timing problems, so this really might be worth a try.

Thanks. Good idea to try.

Clemens Koller wrote:

[snip]

...

You might also try to actively lower/rise the voltages of your board/ram/... a bit. If your problem changes, I would bet it's a hardware problem.

From what you suggested and experience, I'd like to

summary one Golen Rule for firmware debug as follows.

If u-boot can boot sucessfully once and then sth unexpected happened on a board with the same image, in most cases, perhaps X% more, the problem is related to Hardware.

I prefer X equal to 99. Agree?

Any exception and comment is warmly welcome.

Thanks for all your feedback,

Sam

_________________________________________________________ Do You Yahoo!? 150万曲MP3疯狂搜，带您闯入音乐殿堂 http://cn.rd.yahoo.com/mail_cn/tag/yisou/music/*http://music.yisou.com/ 美女明星应有尽有，搜遍美图、艳图和酷图 http://cn.rd.yahoo.com/mail_cn/tag/yisou/image/*http://image.yisou.com 1G就是1000兆，雅虎电邮自助扩容！ http://cn.rd.yahoo.com/mail_cn/tag/1g/*http://cn.mail.yahoo.com/event/mail_1...