User:Samir

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Don't hesitate to correct sentences if they don't sound very english... This is not my mother language.

Notes on the XO B4-10

Initial build 406.14

• B4-10
• Linux-2.6.21-20070614
• Firmware : PQ2C18
• Build : 406.14 variant devel jffs2

First impressions

Opening the XO is puzzling :-) I would say that the first pedagogical activity of the XO is opening it... You have to understand and to watch carefully the XO. The XO is cute, a beautiful object - the keyboard - a waterproof one - is not as responsive as standard keyboard. Need to train before typing quickly. The space bar does not respond well.

The wiki is a jungle... Informations are scattered in a lot of place, not really up-to-date, and informations for B1,B2,B3,B4 are mixed, so it is difficult to focus on your version hardware.

With this build, close an application is not intuitive. Corrected on next build. I suggest anyone to first upgrade both the firmware and the build image. For instance, the first time I tried the XO, I thought that there was a problem with the battery... Because the battery discharged very quickly. In fact, the problem was that this firmware does not control the battery charging very well.

Build upgrade 542

Following the auto installation wiki page, I did this upgrade

• Linux-2.6.22-20070801
• Q2C26
• build 542

I come to this problem, called the "XO Activation error"... In the wiki auto installation, I miss this part, which was important : reboot and push in the same time the 'check' and 'X' button (from the gamepad). Then the problem was gone

The battery seems to last around two hours... there is still a problem, the indication are not accurate in the sugar interface.

I realized that there is a problem with NAND flash, few bad blocks, and sometimes got a CRC error...

No sound for TamTam, but there is sound with the XO, I tried mplayer which plays fine ogg files (tryad on jamendo.com - Public Domain :-)

I tested the "Watch & Listen", too few possibilities concerning the video format. Wondering if I can use mplayer as a backend for "Watch & Listen" - mplayer supports a lot of files, and works well on the XO.

I've got a very weird problem with my home access point (Inventel www.porciello.com/inventel/astuces.htm) The XO cannot connect to this ap out of the box. There is a functionnality called "association mode", a kind of mac filtering. When you push a button on the ap, filtering is disactivate and all wireless computer can connect to the ap. Their MAC address are stored into the ap memory, and when the "association mode" is over, new wireless computer cannot connect anymore. I tested the XO to other APs, and there is no problem... But with this ap, it can connect during the "association mode", and when I reboot the XO, it cannot connect anymore although I can see that the MAC address is registred into the APs. My first hypothesis was that there was a problem with the ipv6 module, but it wasn't that. Now I would try to disactivate the mesh functionnality, to test if the problem come there.

Build 649

• Linux 2.6.22-20071121
• Firmware Q2D05
• Build 649
• driver libertas - COM-USB8388-322.p1.dbg - firmware 5.110.20.p42 (with ethtool -i eth0)

Still a problem with the Inventel AP - maybe "wrong MAC address" problem ? (ticket 4637) - problem mysteriously gone ...

Build Joyride

bleeding edge is http://xs-dev.laptop.org/~cscott/olpc/streams/joyride/latest/devel_jffs2/

Mysterious Update to Build 656

This night, starting the XO with an update I didn't ask for ! Throw all the software I installed before, lot of work gone away. I remember to let the xo with Sugar open into a room with an open wireless access, so I guess that the system has been automatically updated during this period. So I understand why it was configured like this (children are supposed to not customize their XO with their own rpm package ?), so next time I'll try figuring out how to disactivate this annoying feature when you are developer. Fortunately my home directory is intact. Probably the olpc-update-query is involved in this mysterious update, so I'll try to figure out how to disable this feature.

• Linux 2.6.22-20071231
• Firmware Q2D05

Notes

• Big problem with man pages, there are all squizzed... Same with doc. Investigations on the process, before filling a track. The system is globally not self-documented, which is an issue when talking about education.
• Learn to use /dev/shm (tmpfs) to minimize access on the flash card (they might last longer)
• Problem with X11 fonts (we cannot add more fonts)

Currently working on

• Power the olpc XO with the couple battery/solar panel
• Accurate measurements of the power consumption
• Robotic modules for the XO
• VGA output for the XO (useful for demonstrating the XO by itself)
• Bluetooth connection
• Debian-olpc

USB2VGA

• Tested unit : UVT-100 from MCT, also known as eMagic UTV-100 SXGA adapter
• Driver : http://cs.chipsetcomm.com.tw/support/download/USB2.0_TO_VGA.rar
• Spec : chipset unknown
• lsusb gives : 0711:5001
• Need USB 2.0

I've received an usbvga dongle kindly offered from an olpc dev guy (Thanks Josh !). Right now, I'm trying to get it working from XP through the mini-cd driver received with the dongle. The unit is from MCT, the UVT-100 (see http://www.esysmall.com/detail_prod.asp?prod_Id=5544 ) one. Seems to be the cheaper one, I dismantled it but unfortunately the graphic chipset is just behind a cooling component, so I can't read what kind of chipset is used.

More on the USB2VGA UVT-100 dev page

Tips and Tricks

• SD-card and jffs2 : jffs2 is the more accurate filesystem to use with this kind of flash memory, but currently need the blkmtd kernel module to be able to mount the SD-card, if the card is formatted it with jffs2.