New Weather Station

I moved back to California and set up my weather station with improvements. The Weather station is the Davis Vantage Pro. It samples indoor and outdoor temperature, relative humidity, baro015cf72882318a8c701d7e8a95344c2eb81534a0cametric pressure, rain rate, wind speed and direction, and solar radiation detector. A few changes from before: I retired the camera, the weather isn’t as interesting as Washington so felt it wasn’t needed. I retired the 800MHz Cyrex Linux box and retired using wview. The weather station is mounted on a long telescoping aluminum pole I bought from DX Engineering with guy wire system.  We used two bags of post hole concrete to set the pole. It is about 40′ high. The unit has a small lithium battery and solar panel for power. It uses a radio to broadcast weather 01e8a5d2fcafdc0972ba0a5c2d7272bd5945f65cfadata back to the inside station. The inside station receives the weather data and displays on an LCD screen. There is an option which allows remote access to the data over RS-232. Buy the WeatherLink serial package from Davis for the serial converter.

 

 

01db47afd6ce106b955b821fc884f46000ee143477The new station uses a Beaglebone black running Debian Linux. I bought the BeagleBone Black RS-232 Serial Micro-Cape and Expandable BeagleBone Black Case (Orange) from Logic Supply.

The Micro-Cape defaults to UART0; however, can be reconfigured for UART4. For this application, UART0 is used for other things (system messages) and would be better to dedicate UART4 for weather data. This involves moving two SMD resistors to different pads on the Micro-Cape. I edited the file on the beaglebone in /boot/uboot/uEnv.txt and added:

optargs=capemgr.enable_partno=BB-UART4

After rebooting try, ls -l /dev/ttyO*, you should see:

crw-rw---- 1 root tty 248, 0 Aug 11 14:01 /dev/ttyO0
crw-rw---T 1 root dialout 248, 4 May 7 2015 /dev/ttyO4

Weewx

This is an open source weather monitor software written in python.  Download the .deb file from the weewx website and follow the installation instructions here. Once installed, there should be a directory /etc/weewx. edit /etc/weewx/weewx.conf and find [Vantage] and set the following parameters.

type = serial
port = /dev/ttyO4
baudrate = 19200

Weewx software uses html templates similar in function but different syntax to the wview system. They use the Cheetah Generator system for parsing the files in /etc/weewx/skins. The files can be ftp to remote site and/or generated locally in /var/www/weewx.I was able to bring my Steel Series javascript dials over. Cheetah templates are more scriptable than wview which is handy when getting around some of the anomalous outputs such as wind speeds of zero.

#if $current.windSpeed.raw > 0
$current.windSpeed from $current.windDir ($current.windDir.ordinal_compass)
#else
Calm
#end if

Weewx also supports web pages specific for mobile and smart phone devices.

 

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