ThingSpeak is one of the newest of several web sites where you can upload data to their server and then retrieve your data in the form of charts and graphs. You can view these graphs on their site or you can place them on your personal web site. They have an extensive API to configure the graphs and your data. The primary restriction seems to be that you can only retrieve 8000 points at one time. You are also limited to uploading no more than every 15 seconds. So if you upload every 15 seconds, you can only view about 32 hours of data on your graphs. However, if you uploaded every 10 minutes, you could view almost 2 months worth of data. The choice is up to you and it depends on the nature of the data you are uploading. The charts can be static and you would refresh your browser window for new data or you can configure the charts to be dynamic and automatically update.
The ThingSpeak plugin for HomevisionXL lets you enter your personal APIKEY (obtained from ThingSpeak) as well as choose the rate that data will be uploaded and up to 8 HV variables that will be uploaded at that rate. So let's get started.
The first step is to go to www.thingspeak.com and register for a new account. Once you are registered, you can go to Channels and add a new channel. A new channel has 8 fields and the configuration for a new channel looks like this:
Here you can fill out the information that pertains to your application. Here's the data for the channel I used to test the plugin:
The only difference is that there will be a 16 byte value in the API Key box. Write this down as well as the channel number for configuring the ThingSpeak plugin. That's all you need to do on the ThingSpeak end.
Using the HomevisionXL
application, go to the Plugin Manager
using the Wizard, select the ThingSpeak plugin to have it downloaded
and installed. Finally, enable the plugin you just installed
close the Plugin Manager. Now select Plugins from the
menu and ThingSpeak from the Plugins menu. This should
the following dialog box:
There are a number of options for displaying your data. If you have configured your channel as a public channel you, or anyone else, can view your channel graphs on the ThingSpeak site. Here are my plugin testing graphs.
If you login to your channel, you can also view your graphs but with more options to manipulate your graphs and charts. Here's what the graph page looks like when you're logged in:
As you can see, you can also modify many of the parameters of the graphs and how your data is displayed.
Finally, once you have the graphs configured the way you want, you are provided with the code to embed these charts in your own web page. Here's a sample of a few graphs on one of my web pages. You can also see information about more plugins on my Home Control Page.
I also have a page with code and information to upload data to ThingSpeak directly using an Atmel AVR controller and a Wiznet module.
You can download the new plugin from the HomevisionXL download page or directly from HomevisionXL using the plugin wizard.
Please feel free to contact me with any questions or suggestions for improving the plugin.