Osmo-lea6t-gps » History » Revision 3
Revision 2 (laforge, 02/19/2016 10:48 PM) → Revision 3/12 (laforge, 02/19/2016 10:48 PM)
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= osmo-lea6t-gps =
The swiss makes of GPS receiver chips and modules u-blox has (among others), a line of so-called ''timing'' GPS modules.
The main difference of such modules compared to the standard modules is their ability to output arbitrary GPS-derived clock
signals anywhere between 0.25 Hz and 10 MHz.
This allows such modules to be used in a varity of high-precision timing applications where a simpler/traditional approach using
regular 1PPS outputs is not sufficient.
The Osmocom project has developed an evaluation / development board for the u-blox LEA-6T timing module. Like all other
Osmocom projects, it is fully open source, i.e. schematics and layout files are freely available.
[[Image(osmo-lea6t_small.jpg)]]
== Electrical Design ==
=== Schematics and Layout ===
The most up-to-date versions of the schematics and layout files can be found in the projects git repository which can be
browsed at http://cgit.osmocom.org/cgit/osmo-lea6t-gps/ or cloned like this:
{{{
$ git clone git://git.osmocom.org/osmo-lea6t-gps
}}}
=== Major components ===
* LEA-6T Module ([http://www.u-blox.com/en/gps-modules/u-blox-6-timing-module/lea-6t.html product page], [http://www.u-blox.com/images/downloads/Product_Docs/LEA-6_DataSheet_%28GPS.G6-HW-09004%29.pdf data sheet])
* FIXME: add more components here
== How to use ==
You can connect to it using one of the Osmocom-style serial cables (3.3V UART on 2.5mm audio jack) or using USB. You will get
a serial port that can speak either NMEA or the proprietary UBX protocol.
The full protocol is specified in the [http://www.u-blox.com/images/downloads/Product_Docs/u-blox6_ReceiverDescriptionProtocolSpec_%28GPS.G6-SW-10018%29.pdf u-blox 6 protocol specifiation].
== Where to buy ==
You can have the PCB etched anywhere you'd like, using the layout data we have provided. Most of the components
are available via distributors like Digikey. Only the LEA-6T module has to be obtained through an u-blox distributor.
Alternatively, [http://sysmocom.de/ sysmocom] is selling DIY kits including the PCB and all components [http://shop.sysmocom.de/products/osmo-lea6t-gps in their webshop]. Please note that you still have to solder all parts by yourself.