[Xastir] Davis weather not posting rain totals properly

[Curt, WE7U]

On Fri, 4 May 2012, Mike Swiatkowski, AA9VI wrote:

> There is a bug in the APRS string data for the rain totals from the Davis Vantage Pro station.  I can clearly see the day rain, hourly rain, and rain since midnight not being ported to RF or the APRS-IS servers correctly when displayed properly on Own Weather Data..  For some reason when I bring up Own Weather Data all 3 fields are 0 (not the case for all other WX readings).  If I wait a minute they update to the proper number after the new set of data is sent to Xastir every minute.  It seems to me that the data from the 6540 Weather console to serial port interface is reaching the computer but the output string is not being processed correctly in Xastir. The only time I get correct hourly data from Xastir to APRS-IS is if the Own Weather Data box is opened.  The rain since midnight and over the last 24 hrs gets reset to zero multiple times per day. 
>
> So, here's how I am sure it is Xastir.  Note the data 000 following p and P. I also see the p and P fields transposed in the string from Xastir as well.  The APRS spec shows p should proceed P not follow it.
>
> string sent to Xastir from Davis 6540 APRS console to serial interface:
> @050240z4207.44N/08747.20W_021/001g001t054r000p035P035h85b10157.DsVP
>
> string sent from Xastir to APRS-IS:
> @050241z4207.44N/08747.20W_360/001g001t054r000P000p000h85b10157
>
> I am using Debian 6 and the latest CVS Xastir 2.0.1. 
>
> I'll try and dig into the source code but being a novice, I'd appreciate it if someone can help me find what's wrong.  All other weather data including temp, humidity, wind speed/direction are all working correctly.

First:  I don't have any Davis gear so I cannot test this out myself.

Second:  Are you running the special code in the xastir/Davis subdirectory?  In order to support Davis equipment you have to be running that plus some other S/W.  Here's the OVERVIEW from the README located in that directory:


   OVERVIEW
   --------

   This is a bridge utility between "meteo", a Davis Weather Station
   data storage & display application by Andreas Muller (see
   http://meteo.othello.ch) and "Xastir", the APRS package for
   Linux (see http://www.xastir.org). It allows your Davis weather
   data to be used by Xastir for local station data.

   You will need to obtain and install Xastir, mysql and meteo as
   outlined in the following sections. After Xastir and meteo are
   in working order, this utility can be run as a daemon to provide
   weather data to Xastir (or any other APRS-format application).

   "db2APRS" watches for new weather data in the database, retrieves
   the new data, formats it in APRS "position less" ASCII format and
   makes it available on a TCP port of your choosing. Xastir is
   capable of reading this data (see note under Xastir installation).


Third:  I also see this entry in the Xastir ChangeLog, so maybe you're running this hardware?

   2009-05-19 13:47  tvrusso

         * config/language-Dutch.sys, config/language-English.sys,
           config/language-French.sys, config/language-German.sys,
           config/language-Italian.sys, config/language-Portuguese.sys,
           config/language-Spanish.sys, src/database.h, src/wx.c: Add
           support for the Davis 6540 "Weatherlink for APRS" with "Streaming
           Data Logger".  This attachment to the Davis Vantage Pro causes
           the device to stream APRS posits (sans fromcall, tocall, and
           path) to the serial port instead of requiring polling.  With such
           a device, Meteo and the associated glue program (db2APRS or
           whatever it's called) are unnecessary, so long as this patch is
           in place.


-- 
Curt, WE7U.        http://www.eskimo.com/~archer
APRS:  Where it's at!        http://www.xastir.org