Archive for April, 2012
For the remote control project, I'm still undecided on whether to use Wi-Fi or Bluetooth LE for connectivity.
Bluetooth LE is still a quite new technology and there aren't many manufacturers of Bluetooth LE chips and modules. Read this article for a good guide to the availabe chips and modules (most of which seem to be based on TI's CC2540 chip).
There's no way I'm going to mess around with the chip itself – impedance matching of the antenna trace and shielding and whatnot are better left in more capable hands. So I'll be using a complete module. And Bluegiga's BLE112 seems nice: it's based on the CC2540 and there's plenty of documentation on Bluegiga's Tech Forum (you need to register to access the documentation which if both free and easy – no NDA's or anything).
However… There are not a lot of distributors of the BLE112. Mouser has it. But it "may require a licence to export from the United States". But I went ahead and ordered a couple of BLE112 modules and a CC DEBUGGER (which is necessary for configuring the BLE112 module).
It turns out that Mouser was not able to export the CC Debugger to Denmark and for the BLE112 I had to fill out an "Customer End-User Certificate" so they can decide whether I'm eligible for getting my hands on that kind of technology or not. (Strangely enough, Bluegiga is based in Finland which is practically Denmark's next-door neighbors.)
I did, however, manage to get a CC Debugger from the Danish branch RS Components instead (since they ship from Europe there is no export hassle) and I'm still waiting to hear from Mouser…
For my day job, I develop iPhone apps. Fairly often people are interested in developing an app that interacts with some sort of hardware device. Usually the setup they envision is not feasible, sometimes it's nowhere near possible. But I digress...
To demonstrate one possible iOS-to-hardware setup, I made a small prototype consisting of a GainSpan GS1011MIE Wi-Fi module, an ATmega328 and a LED (if you understand Danish or know how to use Google Translate, you can read about it here.)
Wanting to build something slightly more useful than remote controlled LED, I came up with the idea of a remote controlled IR remote control (yeah I know, "remote controlled remote control"). Specifically, a remote control that can control everything from TV, DVD, Apple TV and set-top box which is controlled from an iOS app.
Initial ideas in no particular order include:
- Powered by external 12 V (or 9 or 5 V) adapter
- Use both wide and narrow angle, high intensity IR LEDs (just like the TV-B-Gone) so exact placement is not terribly important
- RTC so it can be programmed to perform actions (macros) at specific times
- Use an IR receiver to learn remote codes
- GS1011M Wi-Fi module (which will also allow the device to be controlled from a browser or whatever) or
- BLE112 Bluetooth LE module (in which case the device will not be connected to the Internet but it will allow much smoother integration to the iPhone app)
- Enclosure: either 3D printed (Shapeways) or layered laser-cut acryllic (Ponoko)
Further bulletins as events warrant…
This online 3D Gerber viewer is awesome.
Simply drag-and-drop your Gerber files and it'll generate a 3D model of the PCB which you can pan and zoom and save to an image.