Questions about the usability of GTA02

Sun Feb 1 23:46:31 CET 2009

On Sat, Jan 31, 2009 at 06:11:58AM -0800, Tschaka wrote:
> 
> So, again somebody is asking a question about usabilty. Please don't get me
> wrong, i actually browsed the mailing lists and wikis, but still there are
> some unsure things, and i'd like to have a bit more of a summarization.

> I'm interested in buying an openmoko Neo Freerunner,

   Why? What is it that you expect the Neo Freerunner to do that the other
handheld devices out there won't? You will have noticed that pretty much all
the unhappy users are those expecting the Neo Freerunner to be just another
well polished smartphone. If you buy a Neo Freerunner, do it for the right
reasons so you avoid disappointment.

   For example, the reasons _I_ bought a Freerunner instead of one of the
competing devices:

1) I can install and use the programs _I_ want, even if nobody else sees the
   point. Example: For trainspotting, I want a database with freight train
   timetables and a front end so I can look up train passage times when at a
   station.
2) A screen big enough to do 1). 480x640 is better than most handhelds.
3) A GNU/Linux environment like on my desktop system, which means I can
   basicly do the same things on the go as I do at home.
4) Enough RAM to do 1) and 3). Most such devices have less than 128 MB.
5) An external USB port! Combined with 3), the possibilities are nearly
   endless. Just look at all the USB devices out there, ready to plug in. 
   E.g. even though the Neo doesn't have a built in 3G modem, a USB one can
   be added. The Freerunner also connects fine to a USB cable modem, just
   'ifup eth1' and off you go.
6) Schematics. It brings me the sort of excitement and enthusiasm I
   experienced back in around 1990 when I bought an Amiga 500 and found the
   schematics in the back of the manual. I did some hardware upgrades to my
   Amiga 500 and I'll likely be doing a few to my Freerunner as well.
   See also: The hardware list.
7) Generally, if there's something I'm not happy with on the Freerunner,
   I'll have a much better chance of being able to change it to my liking.
8) I will eventually need a replacement for my more than 5 years old Samsung
   phone. It's not just that the battery has aged noticably, the Samsung
   also has a number of silly misfeatures such as refusing to adjust
   speaker volume while in soundless mode, no way to use sound recordings as
   ringtones and no way of entering '+' in a phone number. See also 7).

   Neither the Android Dev Phone 1/T-Mobile G1, the iPhone or the Nokia N810
live up to all of the above points. I have not carefully checked if one of
the many HTC devices would suit me better.

> 1st) Battery Power
> 
> sometimes i'm at university from 9am to 10pm 6 days a week. I'm often
> browsing mobile news pages with my phone when going to university, or having
> a chat (XMPP of course!), approx 40 minutes a day. In the meantime i'm
> listening to music. 
> I got no actual watch, so my phone is my watch, means i often activate the
> background light to get to know the time. 
> I'm sending like 1-5 messages a day, having a phone call now and then.
> Now and then i would like to access the web via wifi.
> 
> So, since i'm not able to plug the phone to a power source at university,
> would i be able to run it the whole day, without getting out of battery
> power after 10 hours? 

   The following is with the Debian distribution (with ancient 2.6.24
kernel), xscreensaver not installed and GSM off:

Suspended: 20 % battery charge remaining after 3 days.
If sitting idle (not suspended) with the screen blanked: 20 hours[1]. But
7 hours drain 38 % of capacity, which gives about 18.5 hours instaed.
If sitting idle (not suspended) with full backlight on: 5.5 hours[1].
Playing music[2] using mikmod with the screen blanked: 7.5 hours[1].
Playing music[2] using alsaplayer with the screen blanked: 6 hours[1].
Playing music[2] using alsaplayer with full backlight on: 3.5 hours[1].
Shooting video[3] with full backlight on: Well under 3 hours. ;-)

   Some distributions automatically suspend after a while, others don't.
Some distributions don't unblank the screen while locked, so you can e.g.
put it in a pocket while playing music without wasting battery power on
backlight. ISTR this works fine in OM2008.9, but it doesn't in Debian. :-(

   There's a nasty power management bug somewhere which means that if you've
had GSM on and turn it off, power consumption increases a lot:
https://lists.openmoko.org/pipermail/hardware/2009-January/000933.html
I suppose it won't affect you when using the Neo as a phone.

   So in short, I think you should be able to use the Neo for 13 hours on
battery power with the usage pattern you described, just as long as you keep
an eye on the backlight and suspend the Neo during lectures.

[1] Estimated using
/sys/devices/platform/bq27000-battery.0/power_supply/bat/time_to_empty_now,
which doesn't seem to take into account the increase in battery current as
battery voltage decreases. So the estimate is too high.
[2] mod.super-baz from http://www.exotica.org.uk/wiki/Super_Cars_II
[3] See thread at
https://lists.openmoko.org/pipermail/support/2009-January/004464.html

> And, will there be a (software) fix (soon) for the issue, that the battery
> gets uncharged, even if plugged in, as soon as the battery is fully charged?
> (i got no problem charging the phone every night, but when it's fully
> charged at 2am, it would have been running 7 hours on battery power by my
> arrival at university, so the battery would be low sooner)

   The hardware will resume charging when the battery voltage drops to 96%,
but capacity might have dropped "too much" when that happens. A patch was
posted to instead resume charging from software after 15 minutes:
https://lists.openmoko.org/pipermail/openmoko-kernel/2008-December/007354.html
https://lists.openmoko.org/pipermail/openmoko-kernel/2008-December/007355.html

(I think that patch needs an on/off switch, as otherwise, the Neo will no
longer resume charging when suspended or turned off.)

   IIRC, the parts that take power directly from the battery are GSM, the
audio amplifier and the vibrator motor.

-- 
Rask Ingemann Lambertsen
Danish law requires addresses in e-mail to be logged and stored for a year