Sorry if this is a FAQ, but I couldn't locate it. I was surprised to
learn
this weekend that there are undocumented Garmin-protocol commands to
read
out the pseudocode ranges directly from Garmin eTrex receivers via
serial
link. With a static observation position free of multipath, and
post-processing the observed data as a RINEX file along with a
downloaded precise ephemeris this offers the possibility of amazing
precision, even sub 1-meter accuracy with 30 minute observation times
or longer. This is amazing from a cheap consumer GPS. So
far, so good.

My eTrex Summit normally works at 9600 in Garmin mode, but I found the
demo
download of "GRINGO" from Univ. Nottigham communicates with it at any
baud
rate up to 115200. http://www.nottingham.ac.uk/iessg/gringo/
The problem is, the "GRINGO" software that accomplishes this feat (link
above)
seems to be abandoned. Their web page hasn't been updated in four
years, and there was no answer to my email to the address on that page.
Anyone know if this program is still available for sale?

I found there is a freeware implementation of the same idea called
"async / gar2rnx" at
http://artico.lma.fi.upm.es/numerico...antonio/async/
but I cannot get it to work on my machine, it had some sort of serial
port errors.

Links: web page describing some measurements with Garmin G12
http://www.xs4all.nl/~atarist/geo/gps_accuracy.htm
Paper reporting comparison of Garmin eTrex Vista with Leica receiver
http://www.fig.net/pub/morocco/proce..._schwieger.pdf

(E-Mail Removed) wrote:
> Sorry if this is a FAQ, but I couldn't locate it. I was surprised to
> learn
> this weekend that there are undocumented Garmin-protocol commands to
> read
> out the pseudocode ranges directly from Garmin eTrex receivers via
> serial
> link. With a static observation position free of multipath, and
> post-processing the observed data as a RINEX file along with a
> downloaded precise ephemeris this offers the possibility of amazing
> precision, even sub 1-meter accuracy with 30 minute observation times
> or longer. This is amazing from a cheap consumer GPS. So
> far, so good.
>
> My eTrex Summit normally works at 9600 in Garmin mode, but I found the
> demo
> download of "GRINGO" from Univ. Nottigham communicates with it at any
> baud
> rate up to 115200. http://www.nottingham.ac.uk/iessg/gringo/
> The problem is, the "GRINGO" software that accomplishes this feat
> (link above)
> seems to be abandoned. Their web page hasn't been updated in four
> years, and there was no answer to my email to the address on that
> page. Anyone know if this program is still available for sale?
>
> I found there is a freeware implementation of the same idea called
> "async / gar2rnx" at
> http://artico.lma.fi.upm.es/numerico...antonio/async/
> but I cannot get it to work on my machine, it had some sort of serial
> port errors.
>
> Links: web page describing some measurements with Garmin G12
> http://www.xs4all.nl/~atarist/geo/gps_accuracy.htm
> Paper reporting comparison of Garmin eTrex Vista with Leica receiver
> http://www.fig.net/pub/morocco/proce..._schwieger.pdf

What is the point? Will it get you there any quicker?

Dennis Pogson wrote:
> What is the point? Will it get you there any quicker?

GRINGO enables improved accuracy for static observations.
Post-processing GPS RINEX files is not about navigation, since you have
to wait a few days to download the accurate ephemeris anyway. It's about
accurate measurements.

I was hoping someone here would be able to help me find a contact at the
group that (was?) selling this software.

(E-Mail Removed)d wrote:
> Dennis Pogson wrote:
>
>> What is the point? Will it get you there any quicker?
>
>
> GRINGO enables improved accuracy for static observations.
> Post-processing GPS RINEX files is not about navigation, since you have
> to wait a few days to download the accurate ephemeris anyway. It's about
> accurate measurements.
>
> I was hoping someone here would be able to help me find a contact at the
> group that (was?) selling this software.


Like here?

http://www.nottingham.ac.uk/iessg/gringo/

(from a 30 second search with Google)

Phil

Yes... very much like there, except with an email address that is
connected to someone! That web page has a "demo" version of the software
which works great. That's where I started. Problem: the demo is limited
to 1 minute of runtime and then shuts off. You can supposedly buy the
full version by contacting the Nottingham group, but when I tried to
contact them, no one answers. Hence my post here, in case anyone knows
where they went.

Phil Wheeler wrote:
> Like here?
> http://www.nottingham.ac.uk/iessg/gringo/
> Phil

You might try someone here:

http://www.nottingham.ac.uk/iessg/fi...ral/staff.html

Arthur Hass
Reston, VA

<(E-Mail Removed)> wrote in message
news:43fb9c3a$0$58125$(E-Mail Removed)...
> Yes... very much like there, except with an email address that is
> connected to someone! That web page has a "demo" version of the software
> which works great. That's where I started. Problem: the demo is limited to
> 1 minute of runtime and then shuts off. You can supposedly buy the full
> version by contacting the Nottingham group, but when I tried to contact
> them, no one answers. Hence my post here, in case anyone knows where they
> went.
>
> Phil Wheeler wrote:
>> Like here?
>> http://www.nottingham.ac.uk/iessg/gringo/
>> Phil

My own software is much too "green", but if you check
www.precision-gps.org, I will eventually have open-source applications
to collect Rinex data and post-process it. For now, it is mostly a
lightly tested library.

- John Morris
Menlo Park, CA

I had a quick look- this looks very promising indeed, I will look
forward to more developments! Thanks so much for putting this out
there. -John

John wrote:
> My own software is much too "green", but if you check
> www.precision-gps.org, I will eventually have open-source applications
> to collect Rinex data and post-process it. For now, it is mostly a
> lightly tested library.
>
> - John Morris
> Menlo Park, CA
>

(E-Mail Removed)d wrote:
> I had a quick look- this looks very promising indeed, I will look
> forward to more developments! Thanks so much for putting this out
> there. -John
>
> John wrote:
>
>> My own software is much too "green", but if you check
>> www.precision-gps.org, I will eventually have open-source applications
>> to collect Rinex data and post-process it. For now, it is mostly a
>> lightly tested library.
>> - John Morris
>> Menlo Park, CA
>>
I believe the Gringo product was sold to US Positioning and is now
called the RHINO. And is also several thousand dollars a copy.
Terry