[aprssig] Ultimeter 2000 support

Scott Miller scott at opentrac.org
Wed Apr 27 12:33:52 EDT 2005

Thanks Bob.

I think I've hit my limit on freebies (who knew that offering free hardware
on APRSSIG would get such a response? =]).  Thanks to everyone who offered
to help test.

I could use some more data samples of the 'complete' mode, since those
aren't found on the air.  Several minutes of data captured in Hyperterminal
would be great.  Same for Ultimeter II if anyone wants support for that.

If anyone's got some guidelines on hooking up a KPC-3+ in parallel with
proper DCD, let me know.  The dumb Y connection like I'm using won't let the
tracker do carrier detect with open squelch, and there's no transmit holdoff
between the TNC and the tracker since they can't hear each other.  The
external power jumper does save you the trouble of running power to the

50% of the work in implementing the Ultimeter 2000 firmware was just
cleaning up the existing weather code and separating out the Dallas 1-wire
stuff.  It's now got a much cleaner division between the common code and the
parser.  New stations can be supported by just implementing a few functions
(e.g,. wx_station_init(), wx_station_serial(char)) and filling in a data
structure.  Any serial weather stations with a reasonable data format should
be fairly simple to add support for now.

There's still the problem with the WM-918 and similar stations where they
need a negative voltage on the serial input before they'll start talking.
Does anyone have a solution that's more compact than a MAX-232 chip?

Scott, N1VG

----- Original Message ----- 
From: "Robert Bruninga" <bruninga at usna.edu>
To: <aprssig at lists.tapr.org>; <scott at opentrac.org>
Sent: Wednesday, April 27, 2005 9:14 AM
Subject: Re: [aprssig] Ultimeter 2000 support

> This is fantastic!
> By placing one of these at all of the remote WX
> stations, then we will get regular "complete" APRS
> formatted packets that show up directly on the
> D7 and D700's.  Great job!  Bob, WB4APR

More information about the aprssig mailing list