2009-04-01 04:27:30     Write in the Blackfiin register

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2009-04-01 04:27:30     Write in the Blackfiin register

Amine Salmen Rekik (TUNISIA)

Message: 71939   

 

Hello

 

Can you tell me if i can write in the blackfin register when i use uclinux as an OS? indeed i need to configure a timer, so when i write in the register timer11_config, my board reboots.

 

i tried also  to write in the register  FIO2_Flag_S (in order to ligth a led) but when i run this program in my board i receive this error "

 

Data access CPLB protection violation

- Attempted read or write to Supervisor resource,

   or illegal data memory access ...."

 

so can i execute a program in the supervisor mode? if yes, what command should i write

 

thank you very well

 

 

 

 

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2009-04-01 04:32:30     Re: Write in the Blackfiin register

Mike Frysinger (UNITED STATES)

Message: 71940   

 

the whole point of using Linux is that you have the OS which is in supervisor mode and you have userspace which is not.  there is no way at all to run userspace code in supervisor mode.  if you want to program MMRs, you must write a driver.

 

if you want to do portmuxing/gpios though, do not touch any register directly.  there is a framework for managing pins.

 

when in doubt, search the wiki

 

docs.blackfin.uclinux.org/doku.php?id=gpio

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2009-04-01 04:32:55     Write in the Blackfiin register

Amine Salmen Rekik (TUNISIA)

Message: 71941   

 

hi

 

I forgot to say that i use ADSP-BF561_EZ-KIT_Lite as a Board

 

 

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2009-04-01 04:43:34     Re: Write in the Blackfiin register

Amine Salmen Rekik (TUNISIA)

Message: 71942   

 

Hello

 

Thank you for your soon reply

 

You said that if I want to program MMRs, I must write a driver.

 

my question is: if I write a driver i should touch the registers and i think that i will have the some problem.

 

Thank you very well

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2009-04-01 04:49:08     Re: Write in the Blackfiin register

Mike Frysinger (UNITED STATES)

Message: 71943   

 

i doubt it.  you wouldnt get supervisor permission errors when running as supervisor.  by definition, that makes no sense.

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