[U-Boot-Users] help in understand the address of standalone applications, ARM MCU

[Wolfgang Denk]

In message <200805111736.50691.casainho at gmail.com> you wrote:
> 
> I am using an Olimex dev. board with a ARM9, AT91SAM9260 MCU. On my makefile I 

Is this board supported in the public U-Boot git tree?

> am linking with address 0xc100000, "LDFLAGS=-Bstatic -Ttext 0xc100000" -- is 

What makes you think we would know the memory map of your board better
than you?

> this address correct? How can I have sure of that? -- I got this value from 
> makefile of "hello world" example.

As the first step you have to  understand  the  memory  map  of  your
system. We cannot know this.

> When I do "tftp 0xc100000 flash_led.bin" the system hangs.. while If I try to 

Then the address is obviously wrong - seems there is no RAM there.

> do for example "tftp 0x1000 flash_led.bin" the code loads ok but after "go 

Are you sur the code is really stored to this  address?  I  seriously
doubt  that.  0x1000  is  probably an address in flash memory on your
system, and you do not program the flash (normally)  when  running  a
"tftp" command.

> 0x1000", the code does not work... It evens return while shouldn't because of 
> an infinite loop on the code.

You are probably executing random code that happens to be at that
location in flash.

> In the manual of the dev. board I have a memory map that says the 64MB RAM 
> starts at 0x20000000 and ends on 0x23FFFFFF - If I do "tftp 0x20000000 

Ah, see! So what makes you think 0xc100000 could work?

> flash_LED.bin" system also hangs...

Probably because you are overwriting the exception vectors?

> I must say that with my dev. board comes an "hello world" example which is an 
> empty function :-( -- but even I don't know to what address I should load it.

Ask the company who provided that port of U-Boot and the example
program?

Best regards,

Wolfgang Denk

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