Pete Brown, .NET Gadgeteer
- Posted: Dec 02, 2011 at 6:00AM
In today's Hardware Friday post, we're getting back on the rails a bit and highlighting some of the great work Pete Brown has been doing on the Gadgeteer front;
G. Andrew Duthie and I recently gave a fun and informal .NET Gadgeteer-focused talk at the CMAP Code Camp here in Maryland. Unlike most sessions we give, this one was actually recorded (by a couple people even) so there are some videos of the talk on YouTube. I've put them all together in a single playlist, or you can watch the individual parts:
Part 1 (of 7)
The .NET Gadgeteer (I'll call it the Gadgeteer throughout this post) is an open source (Apache 2.0) software and creative commons-licensed standardized hardware platform based on the .NET Micro Framework (NETMF, also Apache 2.0 OSS). You've seen me talk about NETMF before, creating projects using the Netduino and FEZ Panda, among others. Those board follow the Arduino standard layout, and make use of shields for expansion. Beyond using NETMF, there is no standardization for software or communication.
The Gadgeteer lets you prototype devices quickly, without worrying about soldering connections or dealing with different types of connectors.
The Gadgeteer is the brainchild of Microsoft Research. Being both a hardware and software standard, it describes both the form factor for as well as the communications between modules. It also includes IDE support for Visual Studio. This video explains the Gadgeteer concept
The Gadgeteer has turned out to be a great and exciting new platform for .NET Micro Framework developers. It makes it very easy to use existing modules to prototype a product, or just do fun (and useful) projects. However, I'm not a fan of close systems; if the Gadgeteer was closed and didn't easily allow extending, I wouldn't be into it. Happily, that is not the case.
As a part of some of my longer-term projects, I'm considering using the .NET Gadgeteer as the heart of something interesting. That would require designing at least one, probably three or so, different custom modules. Designing a module for the Gadgeteer includes several different components, so I thought I'd try a very simple one here.
The module I've decided to create is a very simple LED module. This has a single regular old LED which can be switched on or off via data sent from the pins. Why an LED module? It's about the simplest circuit you can create which does something obvious with a digital signal.
GPIO (General Purpose Input/Output) pins on the Gadgeteer are 3.3v digital pins. Typically, you don't want to hook an LED directly to a power source (even a digital one); it's best to put in a current-limiting resistor. I chose 100ohms as I had one handy, but even 50ohms would be fine for a standard red LED like what I'm using. Larger values will work as well, but the LED will be dim; too high a value and you may not notice it light up.
For those of us who grew up in the 80s, the back-and-forth red lights on the front of KITT and the Cylons was considered a really awesome effect. It's still popular today, and is even named after Gary Larson, the person responsible for those shows.
Now, a good Larson scanner uses some PWM to modify the intensity of the LEDs trailing the leading light. With the understanding that this is a beginner-focused article, I'm going to pass on that and simply have an LED that moves back and forth, more like the Cylon scanner, less like the Knight Rider scanner.
Here’s a few more links you might find interesting: