Posted on May 17, 2011 at 13:14Hi, I am wondering how do you measure the number of cycles. This relates to your conclusion. :o

Posted on May 17, 2011 at 12:56After power on, HSI is on by default. No need to write any code to turn it on.

Posted on May 17, 2011 at 12:55Usually, a HardFault Exception is caused by access to non-exist memory area. To debug it, you may put a breakpoint at exception handler and exam the stack to check where it comes from when the exception triggered. Know...

Posted on May 17, 2011 at 12:53Try to check section 16.3.3 of RM0008. You may get clue to solve your problem.

Posted on May 17, 2011 at 12:53I do not know what is the nature of your problem. But of course, it is not good to change the system clock while I2C communication is on going. Especially, you changes the clock frequency a lot, from 40kHz to 8MHz. It ...