CareersNG

This section is for those who just want to get started and don't care for too many explanations along the way. It assumes that you are an experienced developer and that your development machine is running a relatively recent Linux distribution.

Unless you know what you are doing, it is highly recommended that you do not deviate from this process. For a more detailed description of this process please read "Setting up a build environment"

Note: If you are using an Ubuntu distribution, it is likely that /bin/sh is linked to /bin/dash. If this is the case, then you will need to change /bin/sh to link to /bin/bash. Neglecting to do this will cause file corruption and your build image will not boot!...this is very true for ubuntu! Run "sudo dpkg-reconfigure dash" and answer no when asked whether you want to install dash as /bin/sh.

First you'll want to check out the source files for Gumstix OE. You should have at least 10GB of free space on your hard drive. With a typical DSL connection this step should take about 20 minutes:

$ mkdir ~/gumstix
$ cd ~/gumstix
$ svn co https://gumstix.svn.sourceforge.net/svn ... stix/trunk gumstix-oe

Gumstix OE requires some environment setup in order to function properly. It is most convenient to set this up via your bash profile:

$ cat gumstix-oe/extras/profile >> ~/.bashrc

As part of the build process Gumstix OE downloads source code tarballs for the linux kernel and other software packages. This next step sets up a global system cache for these tarballs so that they only need to be downloaded once. Setting up a global cache may seem like a lot of trouble for a single user system, but it is often quite useful to set up an autobuilder that runs as a cron job under a separate user account. Occassionaly you may even want to do experimental work under a seperate user account. Setting this up now will save you disk space and download time later.

On most systems you will need to have root privileges for this step. The process below uses sudo, if your current user is not in the sudoers file you will get an error message. If this happens, use su and enter the root password before issuing the commands below (minus the leading sudo of course).

$ sudo groupadd oe
$ sudo usermod -a -G oe your_username
$ sudo mkdir /usr/share/sources
$ sudo chgrp oe /usr/share/sources
$ sudo chmod 0775 /usr/share/sources
$ sudo chmod ug+s /usr/share/sources

Now log out/log in or close your terminal window and open a new one so that the environment changes you enabled above will take effect. Alternatively, you could source extras/profile from the command line.

The build sytem is set up to build for verdex by default. If you want to build for connex or basix you will need to edit ~/gumstix/gumstix-oe/build/conf/auto.conf. Comment out the line that selects verdex and uncomment the line that selects connex.

To build a basic root file system image that includes Linux 2.6.21, boa, cron, and ntp:

$ bitbake gumstix-basic-image

At this stage depending on your PC...but on the average pepare to relax/wait for about 5hrs Also note that you do all installations with a good 24hrs internet connection.

If your build machine is missing any essential packages, bitbake will notify you about them at this point. Install the recommended packages and try the bitbake command again.

Yes bitbake would highlight missing packages...just apt-get or yum them one after the other.


You will also get a message from bitbake suggesting that you install the psyco JIT compiler for better performance. It isn't necessary to install psyco right now, though it is a good idea to install it at some point.

You may also notice another message complaining about not finding user.collection/packages/*/*.bb. Don't concern yourself with this -- you will create this directory later when you create your first package for your own code.

This initial build will take a bit of time since it will need to download all the source code. When it completes, you will find the root file system image and the kernel image in ~/gumstix/gumstix-oe/tmp/deploy/glibc/images/gumstix-custom-verdex(or connex if that is the machine type you selected):

$ ls -1 ~/gumstix/gumstix-oe/tmp/deploy/glibc/images/gumstix-custom-verdex/
Angstrom-gumstix-basic-image-glibc-ipk-2007.9-test-20071101-gumstix-custom-verdex.rootfs.jffs2
gumstix-basic-image-gumstix-custom-verdex.jffs2
modules-2.6.22-r1-gumstix-custom-verdex.tgz
uImage-2.6.22-r1-gumstix-custom-verdex.bin

You'll notice that there appear to be 2 jffs2 images above. However, in reality there is just one: gumstix-basic-image-gumstix-custom-verdex.jffs2 is a link to the actual image, Angstrom-gumstix-basic-image-glibc-ipk-2007.9-test-20071101-gumstix-customverdex.rootfs.jffs2

The "shorter" link name saves typing Your file names may differ slightly from the above since some of them are time-stamped or versioned.

At this point we are ready to update our gumstix with the root file system and kernel that we just built.

First establish a serial connection to your gumstix by launching kermit (the below assumes you are using a USB - serial converter, adjust as necessary)

$ kermit -l /dev/ttyUSB0

The package name for kermit is Ckermit, if you have a system with the normal serial port. You should do: kermit -l /dev/tty0
But note that you might not find your serial port even at tty0, you can also try ttyS0&ttyS1. (If you are using VMware...that might be your experience).


Now set up the serial connection parameters and connect to the gumstix:

C-Kermit> take ~/gumstix/gumstix-oe/extras/kermit-setup
C-Kermit> connect

Tip: Kermit's tab command completion is your friend. Use it to help take the sting out of long path names.

Reboot your gumstix, hit any key to stop the autoboot process and drop into U-Boot. At this point you should verify that your U-Boot version is 1.2.0. If it is not, then you will need to read the section on Updating U-Boot.

NOTE: At the moment gumstix-oe does not yet build U-Boot. If you need to update U-Boot you can find pre-built uboot binaries at:

http://www.gumstix.net/feeds/u-boot

Now we are ready to transfer our new root file system to gumstix RAM, protect the 2 boot sectors, erase the rest of flash, and then finally program the flash.

Type the commands bellow carefully...if anyone fails..its one of those things...just type it again
When you wanto switch to Kermit's prompt you would need to close use Kermit's escape keys....or close your terminal and open another and set Kermit up again.

GUM> loadb a2000000
C-Kermit> cd ~/gumstix/gumstix-oe/tmp/deploy/glibc/images/gumstix-custom-verdex/
C-Kermit> send gumstix-basic-image-gumstix-custom-verdex.jffs2
C-Kermit> connect
GUM> protect on 1:0-1
GUM> erase all
GUM> cp.b a2000000 40000 ${filesize}

Since the Linux kernel resides in its own partition, our final step is to transfer the kernel uImage to gumstix RAM and then finally to flash (don't forget to adjust the filename if needed):

GUM> loadb a2000000
C-Kermit> send uImage-2.6.21-r1-gumstix-custom-verdex.bin
C-Kermit> connect
GUM> katinstall 100000
GUM> katload 100000
GUM> bootm

Everything should work great! Just reboot your verdex...and you shld be up..if you have wifistix or netwifimicroSD, attach it to ur verdex, and boot..it would automatically pick a DHCP address on the wireless interface and you can ssh!

why would I go tru the trouble? If the main attraction is an OS that supports C++ then I think its too much hassle.

I dont need an OS to program C/C++/Java/VB against an embedded device. If you ask me, I thik the gumstick chip would be overly expensive compared to a minimal microcontroller - the 18F PIC series for instance.

In my experience, if you are really Geeky enough to want to build robots/controllers, then picking up assembler should be the target. Many times, you have to go under the hood and debug signal/data bits, and if you are too high level (C, C++) you might be limited. Also, there is nothing better and understanding the nitty gritty of your master chip or processor in embedded electronics - you can only make the most (memory management/conservation, etc) if you know whats in the chip (registers, buses, etc). Having an OS tends to give the false assuance that you needn't worry too much about about the underlying machine, the OS brings a layer/interface most folks find easier to work with.

Why would I want to get married by proxy?

What is better is when your focus is not on hardware electronics of a robot, but some other software aspects... like computer vision, automatic control, ubiqutious computing... etc.

So what Gumstix did is to cover up the hardware programing headache for the high level software guys like me

I think if you are feeling geeky for programming data bits...its better you kuku go and work for a company like Gumstix!
Meanwhile a Gumstix verdex costs $170

Right. You have a point. But sometimes you many find yourself needing to look under the hood.



Did u mean "for the lazy guys like me" ?

How about starting my own company and selling the products to you? No worry I fit give u for $169.

guys i have impatiently gone thru ur post and i have one question. What in the hell do i need this for.. y do i need to write c/c++ programs on this.. what is really the advantage in this stuff.. well pardon me but i just think we taking IT to some psyhomental stage.. sorry u guys.... see u later