[time-nuts] THUNDERBOLT STATUS LED'S

[Tom Clifton]

/snip
Date: Mon, 23 Jun 2008 09:24:35 -0700 (GMT-07:00)
From: "Richard W. Solomon" <w1ksz at earthlink.net>
Subject: Re: [time-nuts] THUNDERBOLT STATUS LED'S

If there is NMEA Data available, there is a design utilizing a PIC chip
that will indicate 3D GPS Fix. It was published by W1AUV. 

73, Dick, W1KSZ
 / end snip

This si something that has been on my laundry list for quite a while.  Some time ago I became enchanted with the PicAxe chip and determined that reading $GPGSA data for the value of 3 is a pretty easy thing to do.  For those not familiar with the picaxe is as a pic with a bootloader built in and a free "Basic-Like" compiler.  While it is somewhat limited in what it can do, and the speed that it can do it, the price is extremely attractive...

http://www.rev-ed.co.uk/picaxe/


$GPGSA,A,3,04,05,,09,12,,,24,,,,,2.5,1.3,2.1*39

Where:
     GSA      Satellite status
     A        Auto selection of 2D or 3D fix (M = manual) 
     3        3D fix - values include: 1 = no fix
                                       2 = 2D fix
                                       3 = 3D fix
     04,05... PRNs of satellites used for fix (space for 12) 
     2.5      PDOP (dilution of precision) 
     1.3      Horizontal dilution of precision (HDOP) 
     2.1      Vertical dilution of precision (VDOP)
     *39      the checksum data, always begins with *