Gratifying Graphic Gizmos

15 years ago, at the start of March | 2 Comments

Yesterday the Current Cost unit actually got installed for real, something I was dreading. Dreading not because it was a difficult thing to do but simply because I expected the figure it would show would be terrible. Guess what, it wasn’t. In fact it seemed to be fairly close to that of other people who are monitoring theirs. The initial figure of 371 Watts didn’t last too long once the dishwasher and oven came on and an interesting spike appeared when the hob went on for the kettle.

Continuing with my sudden graphing fetish, as well as using a Current Cost unit I have dotted a number of little devices I’ve built with Xbee and Arduinos to measure temperatures (and other things) around the house. More information on those will come out later, but it’s an interesting project too.

Since I have the data for those it’d be rude not to graph them too, there’s a sample in the thumbnails below.

Not content with graphing them locally I picked up a Pachube invite and started graphing data there too. The process is simple really and as you can see on the right hand side of this page under ‘Graphy Stuff’, graph images can be embedded in your own or other sites. The really interesting thing about Pachube is that you can share your data with people who may be interested. The data they get to see is delayed by approximately 15 minutes. If you output your data in the eeml format then you can specify your own tags too.

Tagged with: 1-Wire • arduino • development • environment • hardware • monitoring • Pachube • software
March 1, 2009 8:47

Nov

11

Concept iPhone Application

16 years ago, mid-November | 3 Comments

I’ve been messing about trying to learn how to write iPhone apps. There’s a lot to take in but at the moment I’ve managed a concept application. A little shop (of horrors ;). At the moment it simply reads data from an sqlite database and then displays information on the product. The buy now button currently just jumps to the product url at Linitx.com.

Update: Added a screenshot when rotated. The iPhone SDK handles the rotation automatically, all you need to do is specify which parts of which objects move or resize. All that can be done from Interface Builder. Easy as pie. Also note the changed title bar colour, in keeping with LinITX, and the title text. The shop title (LinITX) and shop base product URL are read from a plist file. I suppose they could be read from the sqlite db but I am experimenting so learning how to read a plist file is useful too.

Update 2: Spent ages last night trying to work out why some of the text descriptions for products came out of the database as null. Discovered that when importing the data file it wasn’t using UTF8 encoding, which is apparently all sqlite deals with. Loading up the source data file into TextEdit under OSX and saving it as UTF8 then reimporting solved the problem. I also modified how things are displayed. The image and text are inserted into a UIWebView so are now scaleable by the user. The images are also base64 encoded and in the database. This increases the database size but means the application can still be used offline. Before none of the pictures would display if there was no network connectivity.

Update 3: Added the ability to search the list. The search bar appears when the search button is pressed and hides again when the search is complete.