• Low powered kernel performance testing

    By erbbysam | January 8, 2012

    Testing various linux kernel’s performance on low powered CPU’s -
    http://erbbysam.com/kernel_perf/

    Topics: Uncategorized | No Comments »

    Beagleboard setup and coding

    By erbbysam | October 23, 2011

    Alright, because this process has been kinda difficult and I couldn’t find it all in one place I decided to write this.
    Before I get started, I would like to add a lot of this was taking (respectfully) from:
    http://gigamegatech.com/2010/12/09/beagleboard-xm-and-angstrom-getting-the-big-dog-to-run-at-full-speed/

    Setup

    For your OS on the beagleboard Angstrom is a great distribution with, arguably, the most support right now for the Beagleboard and the Beagleboard-xM with an installer which will work for both of them without configuration. Ubuntu ARM will work as well, but currently has some issues with unlocking the full speed of the xM board.
    For installing Angstrom on your memory card – http://treyweaver.blogspot.com/2010/10/installing-angstrom-on-beagleboard-xm.html
    If you do not want to go through the Narcissus package maker (you should!!!! it will save you many headaches having a new build) I have uploaded my base package that I created here: http://www.erbbysam.com/sdp/sm.tar.gz Feel free to use it as you please, it is a base configuration with only the necessary addons to make it work on a beagleboard. The MLO etc. files are contained in the package and can be extracted by following the guide found on treyweaver.blogspot.com.

    Special Note

    My BeagleBoard-xM has a not so unique issue with the primary partition not booting due to a microSD read timeout. I “fixed” this by pushing the microSD card in and out until it lights up… not elegant but it works. Please see the following email thread I had with the RMA team:

    On Mon, Feb 7, 2011 at 5:18 PM, ME wrote:
    rev=BB-XM-00 Rev B
    name=ME
    issue=fails to read microSD card linux partitions (FAT reads fine)

    On Mon, Feb 7, 2011 at 20:29, RMA Account wrote:
    I cannot see how this could be a HW issue. To the HW, FAT and Linux partitions look the same, just data. I suggest you search the discussion group for the issue that Steve Sakoman found in the Linux kernel where it improperly calculates the time out on reading data from the SD card. I feel confident that this is your issue. I do not have a feel for when this will get fixed in the kernel. I am confident that sending the board in under an RMA will not result in getting this issue resolved.

    RMA Team

    On Mon, Feb 7, 2011 at 8:23 PM, ME wrote:
    This would definitely make sense, after I sent this email I tried removing and putting back in the microSD card, and after a couple of attempts I can make it boot consistently. Thanks you for your help, and I am looking forward to an updated kernel.
    -ME

    It is a real sore spot with me. It has caused us a lot of headaches here lately.

    Good Luck!

    RMA Team

    Usage

    The Package Repository is a great resource to have and was invaluable for tracking down certain packages.

    update/upgrade

    before you do anything else make sure you do this:

    opkg update
    opkg upgrade

    arduino

    with an arduino over usb serial, you will need adm and usb-serial packages

    opkg install kernel-module-usbserial
    There is another adm package that you will need, but at the time, I cannot recall it's exact name

    usb wireless device

    on the xM, the beagleboard has enough power onboard to power an external USB wireless device without the need of an externally powered usb splitter (required on non-xM boards).

    - a simple  Rosewill wireless USB adapter will do, however it will not work out the box. You will need to find the correct package to install it.

    /etc/inittab
    w:2345:respawn:wireless_up.sh
    w:5:wait:wireless_up.shupdate this file: update the channel of the w wireless route, ap and essid
    /usr/bin/wireless_up.sh
    #! /bin/bash
    /sbin/iwconfig wlan0 mode managed
    /sbin/iwconfig wlan0 channel 6
    /sbin/iwconfig wlan0 ap MA:CA:DD:RE:SS
    /sbin/iwconfig wlan0 essid “NAME”
    /sbin/ifconfig wlan0 up
    /sbin/dhclient wlan0
    while true
    do
    done

    I wasn’t able to get a script to run once on startup correctly after the usb wireless device is up, so I simply have a script that respawns untill it is able to connect to the wireless network.

    hostname

    one last minor thing. On you network, the beagleboard will give itself the name “beagleboard.local” which will hopefully make it easier to find once it’s setup. Also, most wireless routers support listing attached hosts which will make it easier to find as well.

    This may be updated eventually. I started writing this just to get some simple information out there on how to use the Beagleboard. This guide is very incomplete, but I hope this article contains enough to at least get you started.

    Topics: Uncategorized | No Comments »

    Why the EZ430-Chronos isn’t a “real” development environment

    By erbbysam | February 22, 2011

    The EZ430-Chronos looks like a great buy. $50 for a full development environment! Well, it is a bit too good to be true.

    EZ430-Chronos

    The ez430-chronos kit comes with a CC1111(USB/RF device) with is programmed with a RF to serial converter program specifically designed for pair and operate with the built in ez430-chronos watch program and therefore cannot work for any new application without a reprogramming. In order to flash the CC1111 with a RF to serial program (software available for download for free), requires the ability to reprogram it, which costs $50 for a kit called “CC-debugger“.

    However, there is hope… via simple python scripts and modifying the watch source code I was able to override the acceleration & time data communication to communication parameters back and forth (a bit of a hack).

    To recompile the watch code I needed to use the “Platinum” version of TI’s Code Composer Studio (CCS) because the free version that comes with the watch has a 4kb compile limit which is smaller than the base watch code. There is a 30 days free trial available on that so I was able to use that, but that isn’t a long term fix obviously. Also, the price on that is absurd. $2-3K for non-student versions. Therefore you can’t even recompile the code that comes on the watch without spending a huge amount of money.

    If the EZ430-Chronos was a “real” development environment and wanted to compete with other cheap development environments then it should either provide everything you need to reprogram the pieces (CCS & CC-debugger) or it should clearly state that “you’re going to be seriously limited unless you purchase the following”. Because they do neither of these things it appears that TI is using the EZ430-Chronos as a loss leader and are forcing you to buy all of these other peices to make it work as advertise.

    If you are looking for the files to modify in the “Sports Watch” source code in order to send raw data (as opposed to the sensor/time reprogramming data) over the preprogrammed C1111 here is a short list:

    ~Texas Instruments\eZ430-Chronos\Software Projects\Chronos Watch\CCS\Sports Watch\simpliciti\Applications\application\End Device\main_ED_BM.c line 18

    ~Texas Instruments\eZ430-Chronos\Software Projects\Chronos Watch\CCS\Sports Watch\logic\rfsimpliciti.c

    If there is any interest I can post my source code here.

    Topics: TI | 6 Comments »

    Updated Host

    By erbbysam | November 9, 2010

    I would post more, if there were 25 hours in each day :)
    I have a bunch of ideas, we will see when I have time to get them posted here.
    In other news, I switched from a crappy shared hosting to SliceHost, could not be happier :)

    Topics: Uncategorized | No Comments »

    Need your vote!

    By erbbysam | August 12, 2009

    Hello blog-readers, I just submitted my entry to the Bing/Gnomedex competition “Will code for Green” and I need your vote! 20% of my final score is going to be how many votes that I receive, and the grand prize is $10,000. I intend to donate a portion of that to charity in the event that I win.

    Instructions:
    1) Goto willcodeforgreen.gnomedex.com/
    2) enter your email address to “login”
    3) find the entry “LEED Supplier Search”
    4) vote for it
    5) Thank you!

    A little blurb about my entry:
    This tool allows contractors and people seeking building material to find LEED certified green building materials using the Bing search engine API.

    Topics: Uncategorized | 1 Comment »

    « Previous Entries