Re: GTA02: NavBoard V3 causing GPS interference
Am 07.02.2013 um 14:36 schrieb Pascal Gosselin: > > Yesterday I was able to confirm that the installation of the Golden Delicious > NavBoard V3 very seriously degrades the performance of GPS when using the > built-in GPS antenna. Getting a 3D fix is taking over 20 minutes on average > using the built-in GPS antenna. When using an external GPS antenna, the > issue goes away and an unaided GPS cold start can be achieved in about 41 to > 44 seconds. > > I suspect that the use of unshielded cabling between the GTA02 is a likely > cause. Being in the Avionics business, I am familiar with the use of > shielded twisted pair wiring, but generally in large 22AWG (will have to > figure out where to source very thin STP cabling). The wires we use to > perform this mod is solid core, probably 30 AWG. In avionics, when it is > desired to keep a signal from radiating outside a cable (such as > Headphone/Microphone wiring), then the shield of only a single side of the > cable is terminated to a good grounding point. When instead it is desired > that the signal inside a cable be protected from EMI/RFI from the "outside", > then the shields on both sides of the cable will be terminated to ground. > > I theorize that only the SCL/SDA would need to be shielded (together in a > shielded twisted pair cable ?), Power and Ground may not need to be shielded. > > This issue seems very similar to the SD Card access/GPS issue of the earlier > GTA02s, so I also wonder if a capacitor fix should be looked at in this case > as well. I am not aware that others have had such a problem but different cabeling may lead to different issues. The key problem with the SD card access is/was that the SD/MMC interface runs at exactly 25.000 MHz and the clock signal switches fast. And 63 * 25.000 MHz = 1575 MHz which is the center frequency of GPS. I.e. the 63th harmonic of the SD interface covers the very weak GPS signals in noise... Damping this SD clock by a 10pF capacitor reduces noise significantly. For the Navigation board the communication is running through I2C. But I don't know the I2C clock frequency. It may be 400 kHz which would mean the 3937th harmonic which is quite unlikely to be the reason (because energy of harmonics goes down by the number). So I rather would assume that the SD clock GND (or VCC) noise or something similar is brought too close to the GPS antenna. Maybe Christoph has some additional hints. BR, Nikolaus ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bt slide keyboard
On Friday 08 February 2013 16:03:14 Alfa21-mobile wrote: > do you know if there is something similar usable with gta? > http://www.usbgeek.com/collections/iphone/products/iphone5-case-slideout-key > board Bluetooth keyboards ought to work. I used to use a Stowaway with an old SHR image on GTA02 but I've not tried it on a recent release, or on qtmoko. That's the first one I've seen with a slide mechanism. If that's what you want your best bet may be to make an adapter for the moko to clip into the iPhone footprint. How are your solid modelling skills? ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Qtmoko v52-armhf : Issue to resume
On Friday, February 08, 2013 04:08:06 PM Adrien Dorsaz wrote: > Hello! > > I've noticed two issues when I resume my phone from suspend : > > * Sometimes my screen kept black and I'm only able to shut down my > phone with power button (I didn't have my computer at these > times, so I don't know if I was able to connect with ssh) > * Sometimes the screen display the last qtmoko image with screen > lock, but it's stuck. Eg, now my screen dipslays 2pm (last > suspend I think), but here I'm at 3 pm now. The only one > interaction possible is to press Aux and see the "^@" strings > displayed. Hmm i guess we need to reproduce it somehow. Maybe automatic suspend resume cycles using rtc alarm could reproduce it - but IIRC i tried it and had no luck. Btw i have been for some time running 3.7 kernel with debugfs mounted - maybe there is some different timing so that this problem is inhibited. You can try yourself. Just add somewhere in statup scripts (e.g. /opt/qtmoko/qpe.sh): mount -t debugfs none /sys/kernel/debug Regards Radek ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: [Community] FOSDEM 2013 - World of OpenPhoenux
Am 05.02.2013 11:50, schrieb Dr. H. Nikolaus Schaller: > for those who did not attend, here are the first photos (most made by me > and some by Lukas) and a movie is in preparation: > > http://www.openphoenux.org/images/ I've created a blog post with my impressions and some pictures, as well: http://blog.slyon.de/2013/02/08/fosdem-2013-impressions/ And I'm looking forward to watching the movie! BR, Lukas signature.asc Description: OpenPGP digital signature ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: GTA02: NavBoard V3 causing GPS interference
Am Friday 08 February 2013 17:10:00 schrieb Pascal Gosselin: > I have found a good reference on how to best handle I2C cabling. It's a > PowerPoint Presentation from Texas Instruments, I made a screenshot of > the relevant image: > > http://s7.postimage.org/t9bfk47hn/Screen_Shot_2013_02_08_at_11_00_03_AM.png > > As I suspected, only one end of the shield gets grounded, individual > coaxes for SCL and SDA. > > Google I2C cable issues.ppt to find the original document as the > first hit. > > Now I have to source some extremely tiny minature coax, ideally with a > solid core (for easier soldering to the pads on the NavBoard and the > GTA02). Looking for recommendations, ideally something I can order from > Digi-Key, Newark or Mouser in smaller quantities (it's not like a need a > 1,000 foot roll!). > > It's not clear IF the power supply wires should be shielded. I think I > will try to see if it makes a difference for the GPS. > > -Pascal You should use fine pitch flat ribbon connector or flat plastic connector like on LCM, and shield it with a metal braid sticky tape, again like originally done in GTA02 LCM connection. For further crosstalk and EMI shielding run a GND wire as every 1., 3. aso wire in your ribbon cable. Ulrathin coax is *extremely* expensive and hard to source /j ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: GTA02: NavBoard V3 causing GPS interference
I have found a good reference on how to best handle I2C cabling. It's a PowerPoint Presentation from Texas Instruments, I made a screenshot of the relevant image: http://s7.postimage.org/t9bfk47hn/Screen_Shot_2013_02_08_at_11_00_03_AM.png As I suspected, only one end of the shield gets grounded, individual coaxes for SCL and SDA. Google I2C cable issues.ppt to find the original document as the first hit. Now I have to source some extremely tiny minature coax, ideally with a solid core (for easier soldering to the pads on the NavBoard and the GTA02). Looking for recommendations, ideally something I can order from Digi-Key, Newark or Mouser in smaller quantities (it's not like a need a 1,000 foot roll!). It's not clear IF the power supply wires should be shielded. I think I will try to see if it makes a difference for the GPS. -Pascal ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Qtmoko v52-armhf : Issue to resume
Hello! I've noticed two issues when I resume my phone from suspend : * Sometimes my screen kept black and I'm only able to shut down my phone with power button (I didn't have my computer at these times, so I don't know if I was able to connect with ssh) * Sometimes the screen display the last qtmoko image with screen lock, but it's stuck. Eg, now my screen dipslays 2pm (last suspend I think), but here I'm at 3 pm now. The only one interaction possible is to press Aux and see the "^@" strings displayed. My phone just fall in the second case and I was able to connect on it with ssh. I've just been able to discuss with Radeck on IRC and we had these results : "top" says me that qpe is using CPU between 10-25% (it's often at 25%). "ls -la /dev/ttyHS*" command gives me : [1] (it seems ok). I wanted to strace qpe and I've seen that it changes pid every 10 seconds, so it seems that qpe can't be runned correctly. So, I've runned : strace -p `ps -A | grep qpe | grep -v qpe.sh | cut -d' ' -f1` and saved it on my server [2]. There's a segfault at the end, maybe that's the error. [1] https://pbin.adorsaz.ch/?c523681d5489944d#KGZlFpPluvLdgI +va6aITvj4hZg1pwKePoELnIqzulg= [2] https://www.adorsaz.ch/public/strace_qpe.txt HTH, Adrien signature.asc Description: This is a digitally signed message part ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
bt slide keyboard
do you know if there is something similar usable with gta? http://www.usbgeek.com/collections/iphone/products/iphone5-case-slideout-keyboard ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Re:
Hm, seems that the best way to spam is to send two mails - publish some link in first mail and ask 'Is it a spam?' in a second =) В Птн, 08/02/2013 в 11:40 +0100, Marc Verwerft пишет: > I sure consider it spam. > > On google you can find a multitude of references to 'altervista.org' : > provaprovax123pr.altervista.org > computing.altervista.org > umanastudios.altervista.org > slotmachinedabar.altervista.org > ... > > This is also the first post of this guy on > comp.handhelds.openmoko.community > > I don't trust it. > > > On Fri, Feb 8, 2013 at 11:25 AM, shamsul hassan > wrote: > is this a spam ??? > > On Fri, Feb 8, 2013 at 8:01 AM, Steve Merker > wrote: > > > ___ > Openmoko community mailing list > community@lists.openmoko.org > http://lists.openmoko.org/mailman/listinfo/community > > > ___ > Openmoko community mailing list > community@lists.openmoko.org > http://lists.openmoko.org/mailman/listinfo/community > > > ___ > Openmoko community mailing list > community@lists.openmoko.org > http://lists.openmoko.org/mailman/listinfo/community ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re:
I sure consider it spam. On google you can find a multitude of references to 'altervista.org' : **provaprovax123pr.*altervista*.*org* computing.*altervista*.*org *umanastudios*.altervista.org *slotmachinedabar.*altervista*.*org ... *This is also the first post of this guy on comp.handhelds.openmoko.community* *I don't trust it. * * On Fri, Feb 8, 2013 at 11:25 AM, shamsul hassan wrote: > is this a spam ??? > > On Fri, Feb 8, 2013 at 8:01 AM, Steve Merker wrote: > >> http://onewayauto.altervista.org/ycf2x5.php?s=lf >> >> >> ___ >> Openmoko community mailing list >> community@lists.openmoko.org >> http://lists.openmoko.org/mailman/listinfo/community >> > > > ___ > Openmoko community mailing list > community@lists.openmoko.org > http://lists.openmoko.org/mailman/listinfo/community > > ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re:
On Fri, 8 Feb 2013 10:25:53 + shamsul hassan wrote: > is this a spam ??? > > On Fri, Feb 8, 2013 at 8:01 AM, Steve Merker > wrote: > > > http://onewayauto.altervista.org/ycf2x5.php?s=lf > > > If it looks like it, smells like it, sounds like it. https://en.wikipedia.org/wiki/Duck_test So I told my Bayesian spam filter to note that mail as a positive. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re:
is this a spam ??? On Fri, Feb 8, 2013 at 8:01 AM, Steve Merker wrote: > http://onewayauto.altervista.org/ycf2x5.php?s=lf > > > ___ > Openmoko community mailing list > community@lists.openmoko.org > http://lists.openmoko.org/mailman/listinfo/community > ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Fwd:
http://onewayauto.altervista.org/ycf2x5.php?s=lf ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community