[U-Boot-Users] minimum bdi config to read flash on 85xx

Jerry Van Baren gerald.vanbaren at smiths-aerospace.com
Fri Sep 14 22:16:12 CEST 2007

robert lazarski wrote:


> OK guys, its working!!!! YEAH!!!! Last problem turned out to be an
> open resistor / bad solder joint on the address bus! We can now erase
> the flash chip entirely. I also did the prog command to upload
> uboot.bin and can see the uboot version at the base address - so this
> stage is now completed!!!! Thanks so much for all the help guys, I
> doubt we would have gotten so far without this community and we are
> most grateful! I feel so much smarter now ;-) .

As do we all. ;-)

> Last question before I get into my code finally - and I'll start a new
> thread when I start debugging: The bdi docs in the uboot manual seem
> to stop at the 'go' command. When I type 'info' I get a running state.
> Can I now just power on and attach a terminal via the serial port to
> get the uboot shell? To get to that point is the next dragon to slay?

Yes.  With the BDI attached you have to type "go" to go (or reset / go 
to start fresh).  With it disconnected, you should be able to simply 
shoot the juice.

Either way, you should have characters coming out the serial port.  If 
you don't it is time to start setting *hardware* breakpoints in the code 
to see how far you are getting.  Note that the BDI can do lots of soft 
breakpoints or a limited (1+) number of hardware breakpoints.  When you 
are executing out of flash, you *must* use hardware breakpoints 
(software breakpoints overwrite the target instruction with a trap, 
which only works in RAM).

> Thanks!!!
> Robert

You are most welcome!!!

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