Nov 072013
 

Tonight we recovered a beagleboard! Many months ago we tried to install Debian and lost video and network access to the device. Obviously, U-Boot wasn’t able to boot the broken Debian install attempt.

beaglebone-black-serialWe attempted to re-flash using the SD card and that didn’t work. So, we thought it was broken at a deeper level and thought serial access would be helpful. A few meetings ago we attempted to build a serial cable that would interface with the BBB. We tried a standard rs232 serial cable and matched the pinout to the BBB board serial pins. Much continuity testing with a multimeter was required to match up pins. Yet, nothing we did worked. Then we realized that its not rs232 and is in fact TTL Serial (a description of the difference). Sam bought a TTL to USB controller and we used a ribbon cable and a breadboard to hook them up.
bbb-ftdi
Once we successfully connected to the BBB over serial we saw the BBB was outputting the character “C”. CCCCCCCCCCCCCCCCCC…..
We asked on irc.freenode.net #beagle and the user magyarm told us that the C output means that the BBB can’t boot and all we need to do is re-flash the eMMC from a SD card. We previously had tried this and it didn’t work so the consensus was that we did it wrong. We retried the flashing of eMMC using the SD and we are happy to report a success!

We downloaded Robert Nelson’s Debian install image at http://elinux.org/BeagleBoardDebian#eMMC:_BeagleBone_Black

Then;

unxz BBB-eMMC-flasher-debian-7.2-2013-10-25.img.xz

dd if=BBB-eMMC-flasher-debian-7.2-2013-10-25.img of=/dev/sd[x] bs=1M

Then place the microSD in the BBB, hold down the boot button, apply power (use the power cord, because when flashing, the BBB consumes more power than the usb cable can provide), hold the boot button until the first LED comes on (this will boot from the microSD card). Wait for the bank of 4 LEDs to stop flashing and go solidly lit, it takes many minutes depending on the speed of your SD card. Once those 4 LEDs are solidly lit, the eMMC is flashed. Remove power, remove SD card and re-power on. It should now boot from internal eMMC!

Instead of blindly trying to flash, we had the serial output of the BBB and knew exactly what was going on the entire time! YAY! Instead of guessing whats going on.

Hardware options:
https://www.sparkfun.com/products/9717
https://www.adafruit.com/products/284
http://shrimping.it/blog/cp2102-kit/

 

Aug 162012
 

Coreboot (formerly known as LinuxBIOS) is a free software project aimed at replacing the proprietary BIOS firmware with a free system for loading and running the operating system.
There are very few laptops available that are able to run properly when flashed with coreboot. Sam has found a lenovo x60 6365CTO tablet and will attempt to use a program called flashrom to put Coreboot (with a SeaBIOS payload) on this machine.
Unfortunately due to limitations of the IBM/Lenovo factory BIOS, flashrom can not detect which of the many flash chips that were used in the various revisions of these machines is present. At least not with enough specificity to be confident that the flash will be correct. So the solution is to disassembble the laptop and identify the chip visually!

At tonights meeting we worked taking apart the x60 tablet. Sam and Rob (Jason helped some too) dug into the tablet and stripped it all the way down to the motherboard. It was even harder to find the actual bios chip, as we did not know where it would be located on the board. We did know that it would be a SOIC8 chip (8 pins connecting to the motherboard) with extremely small writing on it.

Eventually we found a likely part, but after scraping off a sticker (we’ll assume it had a factory bios revision level or some such on it.) Sam declared; “That’s not it, it is supposed to have some writing on it.” The markings are that feint.
After lots of straining with a magnifier we deciphered “SST25VF016B”.

Hurray, a known part supported by flashrom!
 

 

 

 

 

Feb 242012
 

Computer Repair LED

 

The glug’s original kiosk machine for the Baking Company, “the breadbox” has been out of commision for quite a while now.

But the replacement machine, is still a popular attraction and it’s not so cool when it consistently crashes.

There’s suspicion that the problem is an overheating GPU on the motherboard, so during this meeting we’ll be cleaning it up a bit, and trying to manage any cooling issues, maybe with a new fan or two, and probably installing a seperate video card.

So bring a screwdriver and some canned air (or just eat some legumes), and come be part of the fun!

Thursday the 1st of March at SFBC

Nov 032010
 

I had plans to build a widget to track our next meeting. Then I realized I don’t have a lot of time and it would require work… Also, why re-invent the wheel when someone else has already done the work. Events Manager is extrememly full featured. It even has RSS feeds! Hope to see you at the next meeting..

 Posted by at 12:09 pm