Sir,
I am working on Cortex-M4 over serial wire debug protocol, i am able to read IDCODE(0x2ba01477) which is correct as per arm cortex m4 technical reference manual, and i am writing 0x50000000 to CTRLSTAT register to enable CSYSPWRUPREQ and CDBGPWRREQ which is also success without any ACK error,but the thing is when i am trying to read the CTRLSTAT register i got 0xffffffff . I don't understand what might be the problem,Please suggest me what would be the problem??
Thanks & Regards
FLASH_OPTCR looks good to me; excellent!
I think your PWR_CR looks good too. Mine is also 0x0000c000.
I think I'll have to call for jyiu's help now, because I've run out of clues what can be wrong.
Although we're dealing with a problem specific to the STM32F407 at the moment, I just came across this document from ARM about the Debug Interface Architecture: http://infocenter.arm.com/help/topic/com.arm.doc.ihi0031a/index.html
-You can download it for free; you just need to register first.
err....sorry.... I don't think I can help in this STM32F4 specific question.
My suggestion is to post this on STM32 forum and see if anyone there can help.
regards,
Joseph
Well, it was worth the try, thank you for taking the time to look at it, Joseph.
harshan_behra -This is a very special case, only very few people have been working with it, so there might not be many people who can answer.
That means you're in pioneer-land, which is one of the most interesting places to be, but also one of the most difficult places to be at the same time.
If / when you find the answer, please let us know what caused the problem.