Re: Any cure for a washed out keyboard
Hi, the best thing you could do is to put the device (keyboard) into a bathtub with distilled water. No joke! after one or two days the electrolyte ingredients will be washed out. After that drip of the water and be patient one or two days. The device has to be very dry before you should activate the device. Maybe the display do not like it. I am always treating sunken electronic devices that way, including still cameras. A good alternative is ethanol (but not denatured alcohol!). Best regards, yokoy On Thu, 31 Jul 2008 12:44:08 +0545 Bryan Berry [EMAIL PROTECTED] wrote: The first XO casualty at Nepal's pilot schools a few days ago. A second grader washed his XO because it had gotten too dirty. Thankfully, the display, cpu and motherboard seem to be working fine. The keyboard is non-functional and the mouse is nominally functional. Anyone know a fix for a washed out keyboard besides complete replacement? -- Bryan W. Berry Systems Engineer OLE Nepal, http://www.olenepal.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Any cure for a washed out keyboard
A good alternative is ethanol I mean ethanol 96% , better 99,* % Best regards, yokoy -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Any cure for a washed out keyboard
On Thu, 31 Jul 2008 17:34:13 +0545 Bryan Berry [EMAIL PROTECTED] wrote: Thanks Yokoy! I will definitely try that out. I figured that it was the impurities in the water that screwed up the keyboard not necessarily water itself. Does it have to be a large quantity of water or just enough to fully submerge the keyboard? Perhaps I need a lot of water in order to get enough dissolution The more the better. But the best way is to do it in more than one pass, every time with fresh distilled water. In that way the keyboard has to be submerged fully, not more. yokoy ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: udevsettle takes 33.5 seconds on 2.6.25 master kernels
On Fri, 2 May 2008 12:10:35 -0400 C. Scott Ananian [EMAIL PROTECTED] wrote: So these failures are not isolated to 2.6.25, and are probably not the direct cause of udevsettle taking such a long time. just to talk at large because I had such problems on another system. Removing ide-generic and making ata-generic the default fixed the problem. That problem apeared somewhat around the 2.6.22 release, as I remember. After that, all /dev/hd switched to /dev/sd. Additional it was a big speed improvement. Hope that helps. yokoy -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Where is Walter?
On Wed, 23 Apr 2008 14:05:16 +0200 Bobby Powers [EMAIL PROTECTED] wrote: Maybe we could take a break from talking about the sky falling until we hear something from Negroponte or someone else at 1CC regarding Windows? I think everybody would be glad to hear an official statement and nearly everybody is wondering why we don't get one. No statement is a statement. Anyhow, neither the sugar desktop nor the educational project will die due to the great community and the free software. I am not sure if OLPC aka laptop.org will survive. best regard, yokoy -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: OLPC News 2008-01-26
nice idea. the heater could be an add on, just for the extrem cold areas. yokoy On Sat, 26 Jan 2008 15:22:57 -0500 Benjamin M. Schwartz [EMAIL PROTECTED] wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Walter Bender wrote: 5. Batteries: Carla Gomez Monroy reports from Mongolia that the batteries are not lasting as long as expected. The extreme cold was the first suspect. Richard had Carla collect data via olpc-logbat and ran some tests of his own in the freezer (which isn't as cold as Ulaanbaatar). These data, along with a closer examination of the GoldPeak data sheet, make it pretty obvious that batteries don't work so well in the –20 to –40C range. The extreme cold makes the output voltage drop considerably. The result is that at around the 50% capacity mark the voltage is so low that the low-voltage cutoff kicks in and shuts the laptop off. Richard does worry about when the children take their XO laptops outside while suspended; the power dissipation (and thus self-heating) is at its lowest. It may shut off. The question to work out with our battery vendors is that is it OK to de-rate the low-voltage shutoff when it's so cold. Will this do any damage to the battery? - From the uninformed crazy ideas department: There's a temperature sensor in the battery compartment. If the EC sees the battery temp hit -15C, and at the same time the voltage is, say, 10 mV above the low-voltage cutoff, it could _resume_ from suspend, in order to increase load on the battery, and therefore increase self-heating. This would raise the battery voltage and extend battery life. Mathematically, if effective battery capacity is reduced by cold, and temperature is increased by drawing current from the battery, then there may be a domain in which drawing current increases the battery's effective capacity. This approach would work even better if there were a heating element, or something that could be used as such, near the battery. - --Ben Schwartz -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHm5ahUJT6e6HFtqQRApAeAKChFqO/tK82a7PDBAPMxV6HHbxuKwCeOkZv qIa4eIwJbYhOhJ9XE7O4EGY= =jqXT -END PGP SIGNATURE- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: PDF reader not really user friendly...
On Sat, 26 Jan 2008 21:11:31 + (GMT) [EMAIL PROTECTED] wrote: the OLPC software should not be any different. in general, the OLPC software is and should be different. Maybe not in this case, if the solution is fine. If the current solution is not fine, the XO software should be better and due to that different. yokoy -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: can suspend be prevented ?
Hello, On Sun, 13 Jan 2008 00:51:39 -0500 Chris Ball [EMAIL PROTECTED] wrote: Hi, Earlier, had not noticed my G1G1 going into suspend. Now, with 681 + d08, it does so when left to sit. Unfortunately, after suspend my wired connection no longer works after the system wakes. Can I prevent suspend from happening? Yes, with touch /etc/ohm/inhibit-suspend. (And rm it when done.) I think, sugar should take care of this if an activity do not want the suspend feature. When the suspend locking activity has been finished and there is no other activity that is locking the suspend /etc/ohm/inhibit-suspend could be removed. Maybe an activity could attache a line in /home/olpc/.inhibit-suspend with it's activity name. When the activity is done, this line will be removed from itself or sugar. If there is no line left in this file sugar could remove /etc/ohm/inhibit-suspend. [Seems to me such a situation can occur with a child -- what if he is running a science experiment powered from the OLPC USB bus? He would not want his experiment interrupted by the OLPC dropping power (as happened to my USB-keyboard when the XO suspended).] Yes, we've considered refusing to suspend when certain classes of USB devices are plugged in. This hasn't been implemented yet, though. Classes and activities could use the same file as mentioned above? yokoy - Chris. -- Chris Ball [EMAIL PROTECTED] ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: can suspend be prevented ?
hi, On Sun, 13 Jan 2008 11:55:55 -0800 Joshua Minor [EMAIL PROTECTED] wrote: Some screensaver APIs have a method to defer sleep/screensaver by a given amount instead of turning it off entirely. This would let you solve the issue without fear of accidentally disabling it permanently (for example if your activity crashes before turning it back on). I thought SUGAR takes care about crashed activities? A few lines of extra code in SUGAR costs less than an extra screensaver, I guess. If this is not true the screensaver API could be a nice way. yokoy -josh On Jan 13, 2008, at 1:48 AM, [EMAIL PROTECTED] wrote: Hello, On Sun, 13 Jan 2008 00:51:39 -0500 Chris Ball [EMAIL PROTECTED] wrote: Hi, Earlier, had not noticed my G1G1 going into suspend. Now, with 681 + d08, it does so when left to sit. Unfortunately, after suspend my wired connection no longer works after the system wakes. Can I prevent suspend from happening? Yes, with touch /etc/ohm/inhibit-suspend. (And rm it when done.) I think, sugar should take care of this if an activity do not want the suspend feature. When the suspend locking activity has been finished and there is no other activity that is locking the suspend /etc/ohm/inhibit-suspend could be removed. Maybe an activity could attache a line in /home/olpc/.inhibit- suspend with it's activity name. When the activity is done, this line will be removed from itself or sugar. If there is no line left in this file sugar could remove /etc/ohm/inhibit-suspend. [Seems to me such a situation can occur with a child -- what if he is running a science experiment powered from the OLPC USB bus? He would not want his experiment interrupted by the OLPC dropping power (as happened to my USB-keyboard when the XO suspended).] Yes, we've considered refusing to suspend when certain classes of USB devices are plugged in. This hasn't been implemented yet, though. Classes and activities could use the same file as mentioned above? yokoy - Chris. -- Chris Ball [EMAIL PROTECTED] ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: PIL on OLPC
hi, I am not in front of my XO. As I could remember I did CTRL+ALT+F2 root (enter) yum -y install python-imaging CTRL+ALT+F3 yokoy On Fri, 16 Nov 2007 15:12:25 +0100 Cihan Akkurt [EMAIL PROTECTED] wrote: Hi, Can someone explain how to install the PIL library on the olpc, for Image module use, please. I need this module to rezise and save images for my software. thank you -- ** Cihan Akkurt E-mail : [EMAIL PROTECTED] Msn : [EMAIL PROTECTED] Skype : akkuciha ** -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: radio off guarantee?
moin, On Tue, 18 Sep 2007 14:42:51 +1000 James Cameron [EMAIL PROTECTED] wrote: Do we need a solid way to turn off the RF before it's OK to use an XO on an airplane? Our target market usually won't have this problem. Yes, but the developers need a solid way to switch of the RF. The Test XO target market are developers and sometimes they travel by air. Javier wrote: # killall NetworkManager # iwpriv eth0 radiooff How could we ensure not bringing up the RF at boot time? Which file takes care of this at fedora systems? ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: headtracker / mag lens / macro lens ([EMAIL PROTECTED])
On Wed, 05 Sep 2007 12:40:38 -1000 Mitch Bradley [EMAIL PROTECTED] wrote: [EMAIL PROTECTED] wrote: I tried not to move my eyes but my head and looking to the four corners and the center of the XO display. The display is very small so I moved my head really not to much ... Maybe I have got a knot in my brain. I'm pretty sure that if I had to keep my head still to avoid moving the mouse, I would have a knot in the back of my neck after a short time. Whether the knot would then travel to my brain, I don't know. :-) lol after working with the touchpad it feels like having knots in my wrist and fingers. It could not be worse :-) BTW, the activities and sugar need (more) shortcuts to control the XO without the touchpad or mouse. yokoy -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: headtracker / mag lens / macro lens ([EMAIL PROTECTED])
hi, has anybody experince (and libs) with phase correlation? I have no idea how to implement it. Another promising lib is http://en.wikipedia.org/wiki/OpenCV greeting, yokoy On Wed, 05 Sep 2007 19:40:29 -0400 Benjamin M. Schwartz [EMAIL PROTECTED] wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 I am not at all clear on what you are doing, or why. However, you may want to check out http://en.wikipedia.org/wiki/Phase_correlation this is the most accurate possible method for recovering the position of a moving object. If you have a fast FFT available it may be quite efficient. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: headtracker / mag lens / macro lens ([EMAIL PROTECTED])
Hi, On Thu, 06 Sep 2007 14:55:31 -0400 Benjamin M. Schwartz [EMAIL PROTECTED] wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Have you ever used a IBM/Lenovo Thinkpad laptop with the red joystick-mouse in the middle of the keyboard? These use the position of the joystick to control the velocity of the cursor. I am using one right now, and I find it quite effective. The joystick only is able to record a few positions, but because it is used to set velocity, the effect is very high precision. This might allow very small motions to be used, improving comfort. yes, I am sitting at an ibm x20 right now and I like that build in stick from IBM much more than touchpads. On the other hand I used such a stick on a toshiba, too. It was horrible... - --Ben P.S. I have now realized that phase correlation is probably unnecessary for you, because your image already contains a single bright spot. Phase correlation would be appropriate if you wish to attempt this without the reflector, based on the face itself. OK. I still want to realize as much as possible hardware based (well, depends on price). The XO is a slow machine so some time ago I concluded to wipe out unneeded information using IR LEDs and IR Filter. With that the activities should stay usable without slowed down a lot. The board, IR LEDS, reflectiv foil, IR Filter and the resistor costs less than 1,5 Euro. Buying them as an end customer. Put those parts onto the XO board by default would cost only a few cents. Maybe the next generation of XO have intergrated them? A small slot in front of the webcam lense could pick up various filters and lenses. Also suitable for microscope projects. yokoy ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [sugar] Pippy and Calculate
hi, On Wed, 05 Sep 2007 13:00:50 +0200 Reinier Heeres [EMAIL PROTECTED] wrote: ... I just think the two activities are suited for different things. ... yes, I agree. A calculator is not to learn python. Some time ago the calculator activity looks like real pocket calculator and I think that was a good way. I was a bit disappointed about some changes the calculator overcomes. I like the idea to put some interface stuff from the TI89 and the option to program inside the calculator activity. Pippy is more an activity to learn python, did I understand right? So you could also do math in it but it is not in the first place a calculator. I like Pippy (oh, what a sentence. For german ears it sounds like 'I like wee-wee' :-) but it is not the right activity to replace a calculator IMHO. regards, yokoy -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: headtracker / mag lens / macro lens ([EMAIL PROTECTED])
Hello Luke,
I will consider the paraboloid thing, thanks for the code.
I am not tracking only one point. I am tracking a bundle of points - say 5x3 to
20x12 - and it changes all the time with different ratio. Out of those pixels
(and maybe some time) I have to build an AVG Pixel with a defined XY value. AVG
pixel != brightest pixel. For that AVG pixel I could use subpixel, too. I have
to use subpixel because I have to map the low resolution to 1200x900 pixel if I
try to use absolute coordinates.
Where do I get the size 90x30 from? It is not an pixel exact value but a
approximation. It differs.
I tried not to move my eyes but my head and looking to the four corners and the
center of the XO display. The display is very small so I moved my head really
not to much. One infrared filtered result merged from 5 snapshots (four eges
and center) is here:
http://www.olpcaustria.org/mediawiki/upload/7/79/Headtracker_area_small.jpg
It is downsized from 640x480 to 320x240px but the relation is the same.
Maybe I have got a knot in my brain. I really like to get the headtracker
working in a good way without an additional lens.
Again the link to the project site:
http://www.olpcaustria.org/mediawiki/index.php/Headtracker
greeting,
yokoy
On Wed, 5 Sep 2007 12:57:54 -0400
Luke Hutchison [EMAIL PROTECTED] wrote:
PS there's a cheap way you can accomplish subpixel accuracy, as follows.
You basically take a bunch of 1D samples through the brightest pixel,
looking at 2 neighbors in each direction, and then take a weighted sum of
the results. This calls the code I pasted in the last email. It's not
going to be as good as paraboloid regression, but it should allow you to
test feasibility.
// Do a 2D parabolic fit to give sub-pixel accuracy for translational
// registration, by performing four 1D parabolic fits through the closest
// integer correlation offset: horizontally, vertically, and on the leading
// and trailing diagonals. Take the weighted centroid of all four to get
// the true correlation offset.
// off_x and off_y are the one-pixel-accurate correlation offsets recovered
// by correlation.
// x1d and y1d are x and y values for the 1D quadratic fit function
double y1d[9] = { // Get magnitudes at (off_x,off_y) and 8 neighbors
dft_mag(dft, off_x - 1, off_y - 1),
dft_mag(dft, off_x, off_y - 1),
dft_mag(dft, off_x + 1, off_y - 1),
dft_mag(dft, off_x - 1, off_y),
dft_mag(dft, off_x, off_y),
dft_mag(dft, off_x + 1, off_y),
dft_mag(dft, off_x - 1, off_y + 1),
dft_mag(dft, off_x, off_y + 1),
dft_mag(dft, off_x + 1, off_y + 1)
}
// Sum contributions to centroid of each quadratic fit
double x1d_tot = 0.0, y1d_tot = 0.0, x1d;
// Parabolic fit in horiz direction through correlation maximum
x1d = parabolic_fit(-1, y1d[3], 0, y1d[4], 1, y1d[5]);
x1d_tot += x1d;
// Parabolic fit in horiz direction through correlation maximum
x1d = parabolic_fit(-1, y1d[1], 0, y1d[4], 1, y1d[7]);
y1d_tot += x1d; // [x1d is x in parabola space, but y in correlation
space]
// Weight contributions of diagonal by the inverse of their distance
#define RT2_OV_2 0.7071067811865475244 // sqrt(2)/2 (= 1/sqrt(2))
// Parabolic fit in leading diagonal direction through correlation maximum
x1d = parabolic_fit(-1, y1d[0], 0, y1d[4], 1, y1d[8]);
x1d_tot += x1d * RT2_OV_2;
y1d_tot += x1d * RT2_OV_2;
// Parabolic fit in leading diagonal direction through correlation maximum
x1d = parabolic_fit(-1, y1d[2], 0, y1d[4], 1, y1d[6]);
x1d_tot -= x1d * RT2_OV_2;
y1d_tot += x1d * RT2_OV_2;
// Take centroid of all parabolic fits, weighting diagonals by RT2_OV_2;
// make relative to correlation coords by adding off_x, off_y
double subpix_off_x = off_x + x1d_tot / (2.0 + 2.0 * RT2_OV_2);
double subpix_off_y = off_y + y1d_tot / (2.0 + 2.0 * RT2_OV_2);
On 9/5/07, Luke Hutchison [EMAIL PROTECTED] wrote:
Where do you get the size 90x30 from though? Are you saying you can't get
at the full-sized frame through the API currently?
You really should consider fitting a paraboloid over the dot to get
sub-pixel resolution. Note that if the dot is bigger (more than a few
pixels), you probably want to just use the weighted centroid, but if it's
small, a paraboloid is the right approach. You really will get at least a
10x increase in accuracy in both x and y, bringing your effective resolution
to something like 900x300 for the example you gave. You may not even need a
lens. I have used this before with success for an image processing project.
Here's the code for the 1D version:
// Fit a parabola to three points, and return the x coord of the turning
// point (point 2 is the central point, points 1 and 3 are its neighbors)
double parabolic_fit(double x1, double y1,
double x2, double y2,
double x3, double y3) {
double a = (y3 - y2) / ((x3 - x2) * (x3 - x1)) -
headtracker / mag lens / macro lens
Hello, am searching for a cheap mag lens to improve the resolution of the headtracker. http://www.olpcaustria.org/mediawiki/index.php/Headtracker What I have found is a very cheap macro lens. I took it from a one-way-camera and put it directly in front of the web cam lens. The difference is obvious. But I did not find a magnification lens, yet. http://www.olpcaustria.org/mediawiki/index.php/Headtracker#magnification_lens By the way, how could I make high resolution / less compressed pictures and videos with the XO? regards, yokoy ps: sorry for cross posting ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: X trapezoids rendering performance
hello bernardo, Stefano cc_ed you, you saw that mail only once. Ask your provider or your admin :-) yokoy On Wed, 22 Aug 2007 16:58:25 -0400 Bernardo Innocenti [EMAIL PROTECTED] wrote: Stefano Fedrigo wrote: [...] I can't see your mail in [EMAIL PROTECTED] Are you subscribed to it? It's a subscription only list. -- // Bernardo Innocenti \X/ http://www.codewiz.org/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
[olpc-devel] re: no subject
Hi, it would be nice if we have always an additionally subject like [olpc-devel] inserted automaticaly from devel-bounces. I did it this time manually. Otherwise no subject looks like spam... @Mike: please define always a subject thanks, yokoy On Thu, 23 Aug 2007 12:14:45 +1200 Mike Usmar [EMAIL PROTECTED] wrote: OK, hopefully this is an easy question I want to upgrade to build 542, and have the downloaded and un zipped to a UDB drive in boot the olpc-auto.zip, and the latest OS image and .crc file, so in the boot directory I have 6 files q2c24.rom; os542.img; os542.crc; usbupgos.img, usbupgrd.img, and olpc.fth I power up the Laptop and get this message Noot devices /usb/disk:\boot\olpc.fth arguments: [EMAIL PROTECTED]:17:Tyuy_mask? Somebody tell me what I am doing wrong Mike U ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: DejaVu fonts (Was: Ethiopean)
Hello Bernardo, All, I wonder about shipping DejaVuLGC, too. I ask the same questions a few weeks ago on #olpc / #sugar but didn't get an answer. Ok, it is irc and not a mailinglist. Thanks for posting it here. IMHO we should try to switch from DejaVuLGC to DejaVu. Frontiers are not perforce language borders. So it would be fine to have as much fonts on the XO as posible. There is always the chance to switch back. Besides we have less packages and maybe more space for free. Regards, yokoy On Tue, 21 Aug 2007 20:01:17 -0400 Bernardo Innocenti [EMAIL PROTECTED] wrote: (I'm moving to devel@ so we don't need to Cc too many people) Bernardo Innocenti wrote: Sergey Udaltsov wrote: I cannot tell you which font was used by my Ubuntu - I just see those glyphs rendered more of less correctly (see attached). If you're interested, I can provide you with the list of fonts I have installed. I see them just fine in Firefox on my F7 development machine, but not on the laptop. Weird... It turns out that the DejaVu font has the Ethiopian glyphs, but there's also a simplified font called DejaVuLGC which is what we're shipping on the OLPC. I just talked with Walter and J5 and we agreed that it makes no sense to ship a huge font with all glyphs when we're already going to have a custom images for each country where we can easily add language specific fonts. But now I looked at DejaVu to see how bigger it is and it seems to me that it's not worth it after all: -rw-r--r-- 1 root root 448K 2007-08-11 07:42 DejaVuLGCSans.ttf -rw-r--r-- 1 root root 557K 2007-08-11 07:42 DejaVuSans.ttf The RPMs for the complete DejaVu font are even *smaller*: -rw-r--r-- 1 root root 2.0M 2007-08-11 07:43 dejavu-fonts-2.19-1.fc8.noarch.rpm -rw-r--r-- 1 root root 3.3M 2007-08-11 07:42 dejavu-lgc-fonts-2.19-1.noarch.rpm (but that's because DejaVuLGC also comes with Condensed variants). So, is there another reason why we couldn't just switch to it? Currently, we're shipping arabic and thai fonts in all builds. If the DejaVu support for these languages is good enough, we could save even more space. -- // Bernardo Innocenti \X/ http://www.codewiz.org/ ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel -- ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
