From: Wolfgang Denk Date: Sun, 11 May 2008 20:31:05 +0200 Subject: [U-Boot-Users] help in understand the address of standalone applications, ARM MCU In-Reply-To: Your message of "Sun, 11 May 2008 17:36:50 BST." <200805111736.50691.casainho@gmail.com> Message-ID: <20080511183105.B8CDD24764@gemini.denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de In message <200805111736.50691.casainho@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 -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de It is practically impossible to teach good programming style to stu- dents that have had prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration. - Dijkstra