Search found 18 matches

Yes, there's a little "energy storage cell" onboard. It's either a little lithium cell or a supercap of some sort. The exact technology used varies by vendor and board revision. My pharos receiver has ...

http://www.pharosgps.com/products/hp/iPAQ5450/PF080.htm
http://www.pharosgps.com/products/accessories/GPS_Receivers/REC12.htm

Pharos is right: your TTFF should be less than a minute if you have ha ...

Something else - if you've got a Pharos iGPS, there's a pretty good chance you're running the "ES" enhanced sensitivity version of firmware. The software version string reported by the receiver will p ...

not knowing exactly what these cosmetic alterations are, they could very well have affected your receiver performance. I have an iGPS as well, and it's pretty quick about time to first fix even starti ...

DGPS is Differential GPS. It's a technique for compensating for systemic errors by putting a receiver at a known, surveyed location, and then broadcasting deviations in the navigation solution. It's a ...

The SiRF protocol is also far richer. It can express many varied quantities about the internal state of the receiver, signal quality, precise time, constellation status, and allows you to exert far mo ...

A minor addition to this; you may need to grab some too to enable of some of the features (like SBAS support or track smoothing).

Don't forget about host byte order. SiRF sends 32-bit quantities MSB first, but sends 64-bit quantities with the low 32 bits first. Pfff...

On a little-endian machine you want this:
01234567 (RDRO ...

Do a search for the u-blox sirf firmware documentation, perhaps at linkwave.co.uk ... ;) The use of message 5 is strongly discouraged, though my TN200 (GSW2 2.3.1) does generate this message and the d ...

I'm pretty sure no license is required to implement the protocol. I just emailed SiRF to ask for updated protocol documentation, and explained why I wanted it, and they sent the latest revision with n ...

My, aren't we all chatty this week!

Other leads turned up no results, so it looks like I'm stuck with the unenviable task of doing the calculations myself. Between the hassle of re-re-re-re-reading ...

I'm working on adding support into OpenNTPD (and possibly ntp.org ntpd too) for using a SiRF gps as a reference clock. I've got a prototype working pretty well; with a very naive filter and no kernel ...

SiRF message 129 (switch to nmea protocol) or message 165 (set uart configuration).

and to set SiRF mode, send "$PSRF100,0,[baudrate],8,1,0*[cksum]"

All the interesting stuff is done in SiRF mod ...

That looks suspiciously like it might just be starting in binary mode. My TN-200 will output those very strings (well, something similar) in binary message number 255 (Development Information). Try us ...

At the risk of sounding like i'm spamming, I'd like to mention that I've got a GPS toolkit in PERL on the go. It's still pretty alpha (more decoders to write, more control interfaces needed, etc) but ...

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