Categories
Main

Exploring the Netduino #4: Make LEDs *really* Glow (or: Fun with PWM)

In our last entry, “Exploring the Netduino #3: Building the circuit on a Breadboard“, we covered the step-by-step method to wire up the proposed schematic for switching an LED on and off via a power MOSFET. In this entry, we are going to get to the fun stuff: CODE!

But first, a little bit on LEDs

Light Emitting Diodes (LEDs) may function a lot like (incandescent) lightbulbs, but they should never be treated like them. Like lightbulbs, LEDs can be dimmed by controlling the forward voltage. Unlike light bulbs, this range tends to be rather narrow and as such is somewhat difficult to control. Fortunately, dimming LEDs can happen another way that is particularly easy to do with a digital circuit: Pulse Width Modulation (PWM).

Categories
Main

Exploring the Netduino #3: Building the Circuit on a Breadboard

In “Exploring the Netduino #2: (Indirectly) Driving an LED“, we covered the electronic theory of how to use a Power MOSFET to turn the LED On and Off via a digital signal. In this post, we are going to walk the reader step-by-step on how to wire-up the circuit on a breadboard. If you’re using an Arduino, the steps are exactly the same.

As mentioned previously, you will need the following equipment and parts:

  • An electronic breadboard
  • A few common LEDs (like 5mm Red)
  • A couple resistors (a 1 MOhm and a 68 or 100 ohm)
  • N-Channel MOSFET (like RFP30N06LE)
  • A 3.3v power supply or a 2-cell AA Alkaline battery pack (3v)
  • Some jumper wires to connect the circuit together
  • Multi-meter (optional)
  • And a Netduino or Arduino, of course!
Categories
Main

Exploring the Netduino #2: (Indirectly) Driving an LED

In “Exploring the Netduino #1“, you may recall that it was suggested that the reader take a look at the Netduino “Getting Starting” guide found on the Netduino.com site to get a feel for the hardware. The guide walks the user through a “Hello, World” equivalent where the  user ends up getting the blue on-board LED to blink on and off. This tutorial aims to pickup where that guide left off.

Over the next few posts, we will cover how to wire up an LED to control its brightness using the Netduino’s Pulse-Width Modulation (PWM) features and supporting electronic circuitry.

Categories
Main

Exploring the Netduino #1: Takin’ her for a Test Drive

From the last post on Exploring the Netduino, we learned that the Netduino is a lot like the Arduino Uno in physical and electrical aspects, but the Netduino has a few advantages in its court: ~3 times the processing power, 32-bit ARM7, and nearly 30x the RAM. But it was also noted that the Netduino runs a slimmed down version of the .NET Micro Framework (NETMF) which naturally will require more overhead than the native binaries that are compiled down tightly for the Arduino Uno’s ATmega328 8-bit AVR processor.

If you have a Netduino (or are thinking of getting one) and have not yet tried out (or looked at) the Netduino “Getting Starting” guide, I recommend reading it. It walks the reader through setting up their development environment and then writing a simple “Hello, World” type program which gets the little blue light on the board to blink. Unfortunately, this introduction is quite limited and might leave you saying “Well, blinking a blue light was fun, but what next?” Glad you asked!

Categories
Main

Exploring the Netduino #0: Kickin’ the tires

Every tech head with an interest in PICs and Microcontrollers out there knows about the Arduino phenomenon by now. As described by the Arduino folks themselves:

Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It’s intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.

Except for those of us who spend the bulk of our time in a modern “managed” code environment like Microsoft’s .NET — Sure, we all got started on languages like ASM, BASIC, C and C++, but having graduated to these higher level languages like C# and Java, it’s really nice to have a modern, intelligent IDE (like Visual Studio) to work with and not have to worry about things like malloc() and garbage collection.

Enter: the Netduino

The Netduino