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Bootloader to Application

Question asked by joe hinkle on Oct 30, 2016
Latest reply on Oct 30, 2016 by Butcher

How/What is the best way to pass data from the bootloader to the application on a K64?

 

In the bootloader, I bring the clock up to speed (PLL).  I've read someplace that you don't want to have the application go back back thru the clock setting process as it might hang.  

 

Can anyone verify the clock concern?

 

I'm getting mixed speed results in the application.  Sometimes it at speed and other times - it runs slow.  I can't get more info since the code is in protected mode at this point and I can't connect a debugger.

 

I attempted to pass a flag from the bootloader to the application which tells the application the clock is already up to speed so bypass the setting process.

 

I read somewhere that the registers of the RTC were a good place to pass data.  In the bootloader, I engage the RTC clock and then set a value in RTC_TSR.  When I get into the application, prior to performing the clock function, I check but they are always zero, not the value I place it it.

 

Any other ideas on where to squirrel a few bytes of data during the jump?

 

One last question regarding the jump.

 

I have the ENET operational in the bootloader.  Prior to the jump, I turn off the ENET, turn off its' clock.  My issue is, the ENET does not always come back and work properly in the applicattion.

 

What am I missing to enable the ENET to properly work after the jump?

 

Thanks.

 

Joe

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