HOW TO NETWORK ENABLE YOUR DAVIS...

[goofy]

HOW TO NETWORK ENABLE YOUR DAVIS VANTAGE PRO2 USB WEATHER STATION, RUN WEATHERLINK 5.1 ON MAC SERVER OS X 10.6, AND PUBLISH WEATHER REPORTS TO YOUR WEBSITE

The purpose of this posting is to share my setup and operational experience with WeatherLink and related system elements from the Mac user perspective. This article describes the turnkey implementation of weather reporting to your website.

The reader might find it helpful to create diagrams, refer to application screens and manufacturer's literature while following parts of the narrative as well as have a basic familiarity with the various technologies described.


System Components-Hardware/Software
• Vantage Pro2 Plus ISS (cabled)
• Vantage Pro2 Console with VP2 Cabled Firmware 1.90 www.davisnet.com/support/weather/software_frmwr.asp
• Vantage Pro2 USB Data-logger
• Silex SX3000GB Device Server/SX Virtual Link (Virtual Com Port) www.silexamerica.com/products/usb_device_connectivity/sx-3000gb.html
• NetGear ProSafe Gigabit Switches
• ZyXel DSL Modem/Router
• AirPort Extreme/Airport Utility
• Mac mini Sever/Mac OS X 10.6 Snow Leopard
• Silicon Labs CP2101 Macintosh OSX VCP Driver v2.7 (02/23/2011) www.silabs.com/products/mcu/pages/usbtouartbridgevcpdrivers.aspx
• WeatherLink 5.1.0 software

System Component Connections
Vantage Pro2 Plus ISS-->Vantage Pro2 Console<-->USB Data Logger<-->SX3000GB Device Server<-->NetGear Gigabit Switch<-->DSL Modem-AirPort Extreme<-->NetGear Gigabit Switch<-->Mac mini Server

Station Description
The Davis weather station equipment (Vantage Pro2) was purchased in 2005 and was installed in my backyard observatory. I have updated the firmware to revision 1.90. The observatory, which is about 30 feet from my house, is wired for power, telephone and network sub-paneled off of my house services. For years I mainly used direct readings from the Vantage Pro2 console/receiver. Only recently have I decided to network the station so I could access it from the comfort of my home.

The weather station console is wall mounted and I use a USB extender to feed the data-logger signal in the wall to a corner location next to ethernet jacks. The ethernet jacks run to a structured wiring cabinet in another wall of the observatory that contains a EN Switch connecting to the main switch in my house's structured wiring cabinet through underground conduit.

WAN/LAN Description
My internet connection is through an ADSL Modem/Router (ZyXel P-660H-series). Since I prefer to do my LAN routing through the AirPort Extreme Base Station (AEBS), I asked my ISP to turn off the ZyXel router function and now it only provides the DSL function (the ISP tech support makes a simple flip of a switch to put the router in bridged mode. This causes the "Internet" light on the device to go off and the "DSL" light remains on. I can revert to the Internet router function without calling my ISP by doing a reset procedure on the device). This eliminates the Double NAT problem I would have otherwise had with two routers.

I used one of the EN ports from the ZyXel Modem (in main structured wiring cabinet) to connect to the WAN port of the AEBS (mounted high on a wall for optimal WiFi), then used one of the AEBS LAN ports to connect back to the main structured wiring cabinet to a NetGear Switch, to which other switches or machines in my house are ultimately connected.

Side Note: In another home project, I "home ran" telephone and Cat5e cables to every room in the house from the structured wiring cabinet. This was a good decision as one never knows what is needed at a later date. So when I got Elgato eyeTV HD for Mac (PVR connected to DirecTV in the great room) I could locate the Mac mini server in the A/V cabinet and plug into the network for remote access to the server. I was also able to more effectively extended my wireless by adding an AirPort Express (Access Point) through the EN in my bedroom where I had experienced low signal strength from the AEBS. Now I have full signal strength and can watch live or recorded TV from my iPad in bed.

Router Configuration
Using the AirPort Utility, connect to AEBS and select the Internet menu icon to open the configuration screen. The AEBS Internet Connection is configured to connect using PPPoE using my account name and password (provided by the ISP tech support; this is similar to how the ZyXel WAN page was setup in router mode).

I have a static IP address that my ISP provides at a rate of $5/month plus a one time setup fee of $20. This was mainly a server requirement and the AEBS is set to share the address over my LAN through DHCP and port forward through NAT. When AEBS connects to the DSL Modem, the TCP/IP tab shows my static IP address, subnet mask, router address and DNS servers entries from my ISP. When Mac OS X server is setup to manage the AEBS, it adds itself as the primary DNS server and makes a DHCP Reservation for its private IP address. In the NAT tab, I enabled the default host to be the private address of my server so that it is exposed to the WAN, and enabled NAT Port Mapping Protocol.

Domain Registry
I selected a domain registrar and picked a domain name to register. This costs about $10/year. When this process is completed, the domain you register points to a default address, usually the domain registrar's. Thus, I needed to modify my A Records to point to my static IP address. This is done in the Advanced DNS Settings in the Manage Account page of my domain registrar and is simple to do.

Mac Server Installation and Setup
Once the network was ready, I setup the Mac mini server. My stock Mac mini server has a 2.66 GHz Intel Core 2 Duo processor, has 4GB 1067 MHz DDR3 and two 500GB HDD's. Before installing the OS, I formatted the drives to be a 500 GB RAID 1 (mirror) for performance and reliability. The Snow Leopard Server installation takes about a half hour and I used all the default settings. This was followed by a few basic post-install configurations; essentially making my DHCP reserved IP address "manual", making some DNS entries, setting up web services for my website and aliases, and creating a website folder that would contain my index file and receive the html, jpg files and sub directories (more on this below) from WeatherLink uploads.

DNS
The Primary and Reverse zones are already setup by the installation process. I needed to add a Machine (A) record and any required aliases (C records) to the Primary Zone record, e.g., www, weather, or strings that someone would enter in a web page before my fully qualified domain name (FQDN). It's a good idea to restart your DNS after adding records.

Web
In the Sites tab, select the default Host name (has asterisks as value entries ). Then in the General tab, enter your domain name in the Host Name and select the IP address from the IP address drop down menu. Then make sure the Port is set to 80 (http).
Go to the Aliases tab and add your Web Server Alias, e.g., www.example.com

I added another site with Host Name weather.example.com, used the same IP address and port. As a general rule, sites are unique as long as any one of three things are different: Host Name, IP Address, or Port.
For my weather website, I selected it to point to the Weather folder I created earlier (Path: /Library/WebServer/Weather)
Make sure you enable the site by checking the box and save changes.

Device Server Installation
Install the SX3000GB Device Server by plugging in the Vantage Pro2 data-logger USB in one end and the ethernet in the other and then connecting the power.

Install the SX Virtual Link software on the server (comes with the SX3000GB) . This is the application that makes the connection to the USB device (data-logger). There is also a utility on the disk that is useful for initial configuration. You can use the utility to enter a manual IP address or a browser to access the configuration from its web page. Read the manufacturer's documentation on how to do this. I disabled DHCP/BOOTP, Network PnP, mDNS and manually entered the reserved IP Address, Subnet Mask and Default Gateway (AEBS router). I also made a DHCP Reservation for its IP address in the AEBS router DHCP tab.

WeatherLink Installation
Install the WeatherLink 5.1 software from Davis off the CD. After installation, make sure it's set to run in 32-bit mode. Do this by opening the Applications folder, open the Mac OSX WeatherLink folder, right-click on the WeatherLink icon, and select "Get Info" from the contextual menu. In the window that opens, under the General section, there is a box for "Open in 32-bit mode" that you need to select.

VCP Driver Installation
Install the CP2101 USB to UART driver (Virtual COM Port) that was downloaded from Silicon Labs (link is provided above; the driver on the WeatherLink CD did not work for Snow Leopard). After the restart, check the Network Preferences. Mac will indicate that a new interface was detected (may take a few minutes to show up). All you need to do is inactivate the service. Do this by clicking the Gear button at the bottom, select "Make Service Inactive" and apply the changes. (There is nothing really to configure, since the controller is for a modem which we are not using. The important thing is that this driver will be used by WeatherLink to communicate with the data-logger connected to the device server. This is done in the next section.)

WeatherLink Initial Setup
Launch SX Virtual Link and it should connect to the device "Silicon Labs CP2101 USB to UART Bridge". Find the Optional Settings window where you can specify the auto connect behavior. Here you can fill in the path to WeatherLink in the Applications folder in order to automatically start it when it connects and disconnect when it is closed.

Quit SX Virtual Link and restart. Now when SX Virtual Link starts, it connects to the device and opens WeatherLink.

WeatherLink will give you a message that it found a station and needs to be setup or the ports are not configured if you setup the station previously.

Refer to Davis documentation for the setup if you haven't already and/or if it was already setup, when you get to the Communications Config, you want to set the Port to SLAB_USBtoUART and Baud Rate to 19200 with the drop down menus. You should be able to get your weather information now through the WeatherLink UI.

WeatherLink Internet Setup
I am running 3 weather web pages on my site: Current, Summary and History. These were setup as follows:
• Use the Finder to navigate and create a "Templates" sub folder in your station name folder
• Copy the "Current", "History" and "Weather Summary" folders from the Sample Templates sub folder in the WLink folder for the Vantage Pro 2 into the Templates folder of your station name.
• In WeatherLink, open Internet Settings under the Setup menu.
• The Local Path is the path to the Weather folder that the web server uses. During testing, you can set this to anyplace convenient.
• Enable Local Copy
• Configure profiles as follows:

Profile 1

Upload frequency 5 min Offset time 12:03 AM Download first yes Template Files Current_Vantage_Pro_Plus.htx, davisticker.class* Weather_Summary_xxx.htx Sub directory n/a Current data images all but "Inside set", "ET set", & EMC Sub directory n/a Historical data images Barometer Sub directory n/a Plot span 1 day

Profile 2

Upload frequency 4 hours Offset time 12:03 AM Download first yes Template Files History_Vantage_Pro.htx, davisticker.class* Sub directory History** Current data images none Sub directory n/a Historical data images all but "Inside set", THW Index, & EMC Sub directory History** Plot span 1 month

Profile 3

Upload frequency 5 min Offset time 12:03 AM Download first no Template Files data.htx Sub directory History** Current data images none Sub directory n/a Historical data images none Sub directory n/a Plot span n/a

*Remove after first download
**WeatherLink will create the History folder automatically in the indicated local path if it does not exist.

Note: The Upload frequency is my operational setting. You can set Upload frequency to 1 min when doing testing or any other value that works for you for operational purposes.

If you don't have a Mac server, the setup is the same except you will disable the Local Upload and enable the FTP Upload (with required details) to your website host.

Please refer to the excellent WeatherLink Help files or Davis resources for further details.

Gaa-hulk…Garsch! That was easy!
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[goofy]

ADDENDA and ERRATA to HOW TO NETWORK ENABLE YOUR DAVIS...

ADDENDUM in reference to the Station Description section

I'm not sure what difference this makes but the WeatherLink Data Logger I'm using is the Davis #6510USB (Windows) that was purchased at the same time as the VantagePro2. This was back in my PC days. The Macintosh part number is #6520, though Davis comments that it is not equivalent to the PC version:

"Unlike the Windows versions, the Mac version does not log data from leaf wetness, soil moisture, UV or solar radiation sensors. It also does not include Citizen Weather Observer Program or GLOBE Program capabilities, and may not be used with E-Mail/Phone Alert or Agricultural/Turf Management Modules." -Davis www.davisnet.com/weather/products/weather_product.asp?pnum=06520

I do not have leaf wetness and soil moisture sensors on my Vantage Pro2 but I do have the UV and solar radiation sensors and data from these do come across in my Mac downloads from the PC data logger.

ERRATUM in reference to the WeatherLink Initial Setup section

Communicating at 19200 Baud, especially for data downloads, is prone to data transmission errors. This is manifested by the following symptoms in WeatherLink:

The download process from the data logger to the Mac will appear to work correctly, any where between a few download cycles to download cycles over a few days but then the process hangs as follows (per recall):
1. The Local Transfer window shows "Initializing Transfer…please wait…, the directory path is not populated and the progress bar is stuck at 0%.
2. The Local Transfer window shows "Transferring: xxx.html or xxx.jpg, the directory path is populated, and the progress bar has anywhere from no progress to 90% progress but cannot complete the process.

Solution
Setup communications at a slower transmission speed.
1. On the Mac: Quit WeatherLink and SX Virtual Link
2. On the Console: Manually set the Communication rate to 9600 Baud (refer to Davis documentation)
3. On the Mac: Launch SX Virtual Link. This should automatically connect to the data logger and launch WeatherLink. If not, do it manually.
4. WeatherLink will inform you of a communication error.
5. Go to Setup/Communications Config.
6. The Port should still be set to SLAB_USBtoUART
7. Change the Baud Rate to 9600 and test.

This should resolve the data transfer hang problem.

Gaa-hulk! "Winning"

[goofy]

One More Thing…

Addendum in Reference to WeatherLink Initial Setup Section

An additional setting is required to resolve the potential data transfer hang issue: the SX Virtual Link device server LAN Interface setting should be set to 10 Half Duplex.

How To

From the browser, type in the IP address of the SX device server (or, if you don't know, go to the SX Virtual Link window, click the Properties button (lower left corner) to view the properties information of the device. Then click the Device Server Properties button) to open the web configuration page and login (default is root with no password). Click Network Settings and set the LAN Interface from "AUTO" to "10 Half" and submit, then exit.

Discussion

The LAN Interface setting looks like a major factor in the Local Transfer process hang issue. The specifics of all that's going on with the interfaces between the UART-USB-ETHERNET devices and the various protocols and drivers used is a mystery to me. Vendor tech support was unfruitful or guidelines were unavailable for this issue so I was left on my own.

My hypothesis is that there is a problem with auto-sensing the link type somewhere along the way, either on the data logger-SX side or SX-computer side (WLink/USBtoUART) and is responsible for the flow control (handshaking) of the data transmission/data reception between the devices so that a mismatch causes the data transfer process to hang (break down).

Most likely the computer-end communications overwhelms the modem when the link is in auto or full duplex mode (simultaneous sending and receiving). By manually setting the LAN interface to half duplex, any one device on the LAN can transmit but it forces the other device to wait for data transmission to be completed before sending its data to be received by the other. Thus the half duplex setting is a way to manage the communication problem and prevent buffer overflows or corruption.

Conclusion

Whether my theory is right or wrong is debatable, but I can state confidently that the half duplex interface setting works perfectly and is stable under my system topography and operating conditions. To verify, I periodically monitored the WLink Local Transfer process for 5 consecutive days to proof my postulate. The process worked without a hiccup, while, in addition to the full complement of web services, I was running a fairly resource intensive application (Elgato eyeTV HD to record TV programs and act as a host server to view live TV through the eyeTV app on my iPad) as well as performing normal server maintenance such as installing application or system updates (that did not require a restart) or managing/configuring various server services. In the negative case scenario, i.e., if I set the LAN interface to auto or full duplex, the Local Transfer process broke down eventually and resulted in a hang; corresponding to the initial problem that brought my attention to it.

Final Note

It is interesting to note that I used to run WeatherLink at 19200 BAUD on my MacBook Pro with the SX3000GB interface in auto LAN Interface mode for several months without encountering any issues. Back then, I was just running the Bulletin through the GUI and I was not doing any data transfers for web publication. This was the basis for my initial Mac mini server setup. Now, it appears to me that there is a difference in how these two processes work.

Please reply to this series of postings if you found my WeatherLink system setup tutorial helpful.
__________

[goofy]

Hang Issue Update: USB Isolator Fixes Hang Problem

I would like to revise my prior post and say that my theory on the communication problem causing hangs with download transfers was off the mark. It was just a matter of time before the problem returned. For what it's worth, It is very difficult to determine the cause this type of problem without having the diagnostic technology to do so.

With additional research and testing, I now believe that the problem is due to signal spikes and or ground loops in the USB connections.

Here are some links that I found useful:

www.cygnal.org/ubb/Forum9/HTML/002171.html

www.analog.com/library/analogdialogue/archives/43-06/USB_isolator.html

The answer to this is problem is the insertion of a USB Isolator between the USB Datalogger and the SX3000GB Device Server.

There are several manufacturer's of USB Isolators to choose from: Black Box, B & B Electronics, Acromag, etc.

I am now running the system fault free with the USB Isolator with the communications configuration reverted to 19200 Baud.

Note: While I was continuing the research on this problem, I set up a client computer in the observatory, connected the WLink USB datalogger directly to it (eliminating the SX3000GB device server), and ran the download transfer process from a user account I setup on the server dedicated to this purpose. This setup ran perfectly but of course added to the complexity, maintenance and energy costs of running another computer (which I seek to avoid).