Re: Fault when disabling JTAG (?!)
2012-03-05 13:15:35 GMT
On 05/03/2012, at 23:26, Gregory N wrote:
>> I have an STM32 "Strive mini" board from ebay and I'm trying to get nuttx running. I copied the stm32 hymini directory and can run the basic nsh2 demo. I found that it disables JTAG (which seems a little odd for a demo project IMO) so I added the following to .config
> I agree that is it a little odd. It is not a problem for me because I use the DFU bootloader. The person that added that logic was very concerned about power usage and kept everything disabled unless needed.
>> Any ideas? :)
> This is a pretty common place to crash when you bring up a new board. You are starting the very first task and it fails as soon as it tries start the task. This means that something is not set up correctly in the environment when the task started.
> armv7-m/up_switchcontext.S:94 is the return 'bx lr' from a tiny function that just does a SVC call. This means that the registers were corrected when the SVC call returned.
> Usually this has to do with something like the heap configuration. What values are being passed to the memory manager from up_allocateheap().
> But I do not understand what enabling or disabling JTAG would have to do with the fault you are seeing. All that should do is cause some bits to be set or cleared in the RCC. If that effects the booting of the code, the how it did that is a mystery to me.
I'll double check my work and see if I can come up with some more information.
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
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