Fastest realtime info and gauges - tips wanted!

[gbandera]

Hi,

I am working on a webpage to display only the pertinent information clearly on a display at a local flying club / flight school. The station is a Vantage Pro 2 and the supplied software is well; poor!

As I've used Cumulus at home for some time I thought it would be the perfect solution, but for their needs the Cumulus console itself is too 'cluttered' with info that's not relevant to their normal needs. As a result I have set to creating a web page that clearly displays Wind Speed, Wind Direction (bearing), Average for these and Pressure.

I've got around issues like reducing the average to 2 minutes (as required within aviation weather reporting apparently), but it seems the lag is causing some issues (ie. station > Cumulus > webpage means that current conditions - especially wind speed is lagging by a good 10 seconds behind the WS display).

Before I go spending loads of time, can anyone give me a steer as to what the best I can expect is (in regards to time lag / latency from WS to Web page) and how best to accomplish it?

I have the SteelSeries gauges setup at present and they like them as they are good / clear visual queues. I have augmented these with large 'text' displays using basic tags. I have processing setup as realtime, interval 1 second and the page refresh set to 2 seconds at present. I am using FTP to a loopback address (FTP & Web site is on same PC) to perform the updates, but have not tried Active FTP to see if that makes any difference.

In an ideal world they'd like to have gauges and information displayed that is 'in-sync' with the station display - in reality I don't thing this is achievable (and have said as much), but I'd like to get as close as I can.

Any ideas, tips or comments much appreciated...

[steve]

I think you'll find it hard to get any better than a delay of a few seconds. Cumulus should be updating within a couple of seconds of the console most of the time, but it's entirely reliant on the Davis DLL and the console firmware. You can try to reduce the delay that the FTP introduces by only uploading the file that the gauges need (i.e. turn off the default realtime.txt upload). You can see how long the upload is taking by turning on ftp logging and looking at realtimeftplog.txt. Or, as the server is on the same machine you could copy the file instead of using ftp.

Looking ahead, the version of Cumulus I am working on doesn't have a built-in GUI, but instead has an interface for a browser. So you would be able to achieve a display tailored to your needs without the overhead of ftp/copy of files etc. I don't have a forecast for when this will be available, though, it's still very much a work in progress.

[gbandera]

Hi Steve, thanks for the quick response and info. I'll take a look at making the FTP as efficient as possible, and hopefully can get it 'close enough' for their needs. Interesting on the web GUI front too.

Would you say there is any time advantages in using the Silverlight Realtime gauges over SteelSeries (the latter opted for at present so that the future display of the info remotely on 'i' devices is an option)? Or if a basic text display would be significantly faster? Obviously there is nothing we can do about the manufacturer DLL lag reading from the WS, so I'm interested in thoughts on the most effective / fastest way to get data from Cumulus into a web page?

I can then mock up two options potentially (fastest and prettiest) and the club members can make the choice...

Many thanks once again for the response and info.

[steve]

Use the SteelSeries gauges rather than the Silverlight ones. I wouldn't have thought a text display would be significantly faster, particularly if you minimise the movement time on the gauge. And you should definitely try 'copy' rather than 'ftp', there's no need to use ftp at all if it's on the same machine.