Nokia N900

[Benjamin Scott]

On Sun, May 16, 2010 at 10:08 PM, Bruce Labitt <bdlabitt at gmail.com> wrote:
> Doesn't work that way for a car GPS. Usually takes 5 minutes for a cold
> start even if moving, iirc.

  I just today took possession of a Garmin Nuvi 205W.  Previous owner
claims to have never used it beyond plugging it in once.  He took it
out of a metal file cabinet and said it had been in there for weeks.
When I took it out to my car and plugged it in, it seemed to be ready
to navigate almost immediately.  I was still in the previous owner's
driveway, presumably the last known location.  I played with it a bit
today, and when outside, it always seemed to be ready as soon as it
finished it's startup/splash screen dance.  A couple times I brought
it inside and powered it on, and it complained it had no satellite
signal.  When I brought it back outside it would again be ready
quickly.

  While I hesitate to draw firm conclusions from such meager data, if
I had to suppose: It doesn't seem to be dependent on seeing the sky
all the time to maintain it's ready state.  That is, it does not
appear that it is "always on" and watching the sky even when nominally
off.  If that were the case, I would expect the lack of satellite
signal when indoors would cause it later trouble.  I think it must
either (1) use its last known position as a hint to help it regain its
bearings, or (2) be using some other acceleration technique not known
to me or discussed on this list.

  I will test the "last known position" theory by taking it some place
"powered off", then powering it on, and seeing if it gets confused or
takes longer to become ready.

  Unrelated to the "My GPS is faster than your GPS" discussion, but
relevant to the "Linux friendliness" question:

  It has an apparently standard USB mini B port on the back, which
serves for both power input (to charge the battery) and PC attachment
(for software/data updates).  One of the first things I did was (of
course) plug it into my Linux home PC (Debian 5.0.4, kernel 2.6.26-2).
 The GPS display showed the Garmin logo and a picture of itself
plugged into a computer, but Linux was indifferent.  Looking at the
kernel log, it appeared the GPS wasn't playing nice.  I either saw
nothing at all, or just "over-current change on port".  I noticed that
if I plugged it into the USB hub built-in to my Dell LCD, the hub
would apparently reset, as the kernel would re-detect my mouse and
flash card reader.

  Updating the firmware purportedly requires installing some
proprietary software from Garmin.  MS Windows and Mac OS X are the
only offered options.  So I rebooted into my Windoze partition (XP
Pro, SP3).  Again, I saw no evidence that the OS was even seeing it as
a valid USB device.  The Garmin software also repeatedly refused to
acknowledge the GPS's existence (although it did probe my floppy drive
repeatedly -- does Garmin sell a GPS in 3.5" diskette form factor?).

  Garmin also offers a browser plugin (again, 'doze and Apple only,
although they at least support Firefox on 'doze).  This is purportedly
how one updates the maps on the device.  However, that was not working
either.  The plugin appeared to install, but it said it could not find
the GPS.  I even tried MSIE 8 -- same result.

  Flailing around Garmin's website, I eventually found something that
told me to try downloading and installing some USB drivers.  Earlier I
had been told this GPS did not need any drivers; it's just a USB mass
storage device.  But I gave it a shot anyway.  Lo and behold, Windows
made the "bong-bing" noise it makes when it detects hardware
attachment, and then sprouted two new drive letters.  One had the
volume label "Garmin" and appeared to contain GPS-ish files.  The
other said no disk; based on the Device Manager name, I'm pretty sure
it's for the MMC/SD expansion card slot in the GPS.

  Anyway, now I was able to run the Garmin software update tool, which
updated me from 5.80 to 6.40.

  When I got back to Linux (ahhhhh), the kernel now sees it as two USB
mass storage devices.  The internal storage appears as a "vfat"
compatible filesystem.  I don't know if it was the software update
that fixed that, or if my gyrations on the 'doze side just unwedged
something, or if the PC reboot did it, or what.

  So, in conclusion, first impressions: Fast to acquire location
(yay!).  Software/map updates require an OS from an evil dictatorship
(boo!).

-- Ben