The most likely error to occur is that some tarball
has disappeared from the download location.
Typically because the maintainer has released
a new version and deleted the old.
If this is the case, search Internet for the tarball
and download it to the buildroot download location
(Default is /usr/local/install/downloads)

Hey ulf,

Thanks for help, but not certain that will solve my problem. I mean, I DID get an output file, and the compiler will gripe if my code is not syntactically correct. BUT - for whatever reason, the linux demo on the board refuses to acknowledge the presence of the file.

Hi there



But if you type
cat helloWorld.out
do you get (garbage) output?
Please make a distinction between the file existing and being able to execute it.




Shell lesson #63: when you're trying to execute a program, and you get a message like that above, this almost always means a missing library or some other file (.conf?) that the program is trying to open is not accessible.

I'll bet dollars to donuts that you compiled/linked your hello_world program without specifying static linkage to the libraries. Since GNU libc is about 8 megabytes, it is not distributed in the linux demo you have. (The huge size of GNU libc is reason for the existence of uClibc that Ulf pushes.)

Try adding the -static switch to your compile line.

Regards

Hey blue_z,

THANKS SO MUCH!!! You're right, I was unable to execute it. But for a noob like me, the error I got seemed to state the file didn't exist. Anyway, the -static switch worked perfectly!!! I'm super happy! You forum guys rock!

Thanx for this useful information. I have a guys here that have the same problem on the avr32 and linux. So i'm pretty sure is the same problem. For now we have put the stdlib on the target but this is not the cleanest way to do it.

Jonathan

Hey guys, I want to thank you for the help I've received, but I was hoping you could help me once again. The first, is there any way to get the linux demo to auto-execute a program on startup? I was told linux uses a file called ".bashrc" for autoexecution that goes into your home folder. Problem is, the ONLY files that won't revert back to their initial state are those in "media/usbdisk". (And in this case, .bashrc doesn't exist, and thus disappears on power-off) Any ideas around this? (media/usbdisk is the path to my usb disk, whereas I believe the rest of the linux demo resides on flash)

Oh, and on another topic, it looks like there are three sets of pins (1-31 pins with ground and 5+V 3.3+V) in blocks/ports A,B,C. Any idea how to control the logic of a given pin? Thanks for your time.

Hi there

The Linux demos I've seen for Atmel have a copy of the root filesystem loaded from flash memory into a RAMdisk (allocated from main memory) on boot. So a fresh copy is always loaded. Any subsequent changes to the root filesystem are only to the RAMdisk, and no changes propagate back to flash.

You would have to rebuild the image for the root filesystem with any modifications to change the Linux startup. Or you could specify a differernt root filesystem (NFS ?) when U-Boot passes the command line to the kernel (" mem=... console=... ".


Are you refering to the GPIO pins?
Most of these pins are used by the processor (address lines) or the on-board peripherals. Only a few are actually unused. They're "general purpose" at the hardware design stage. It's a board/implementation issue, so look at your board documentation for what's used and what's available.

There are a few threads on GPIO use. Basically I would write a driver to "claim/own" the pin, and use an ioctl() to program it from an application.


Regards

Hi there

Correction to my previous post: Linux 2.6 uses a ramfs, not a RAMdisk. The distinction is described in:
http://linuxdevices.com/articles/AT4017834659.html

Regards

Blue_z and arm_noob,

Did either of you find a tutorial to get you started? Or did either of you write steps to get your program running? Did you use Linux 2.6 ?

I want to get involved in embedded systems as well, but I know even less than you two.

Maybe you two can point me in the right direction since you were where I was only a month ago.

Thanks. kevinj.

Hi there

I doubt that we started from the same point. When I started using Linux last year I had the advantage of many years of embedded SW development (assembly language, 8-bit uP, roll-your-own micro kernels) and about 5 years hacking on the kernel at a major Unix company.

The first Linux board kit I evaluated was from SSV Embedded Systems, and they include a CD-ROM with a lot of helpful info (eg step by step downloading and installing a kernel using tftp and U-Boot) and utilities (Ethereal and a Windows TFTP server). Some of the docs are at their site: http://www.dilnetpc.com/dnp0072.htm
In comparison, the Atmel EK came with an obsolete DVD-ROM that had zero info on the 9260 board. That may be one way to steer you to LinuxLink.

I took advantage of the free 30-day subscription to LinuxLink. At the time it was definitely the easiest way to get the latest kernel for the at91sam9260ek. The last I read, they're still on 2.6.19, and customers want some of the latest patches, like the Ethernet TX underrun fix. But LinuxLink/TimeSys does offer a lot of startup docs, although their local search engine is lame.

Google has been invaluable. Knowing the jargon helps get meaningful search results. Or using the keywords of error messages or phrases can get reports of similar/identical problems and possible solutions.

Regards