Develop embedded apps with ease

BANGALORE, INDIA: Embedded application development has come a long way from writing code in error prone assembly language. Earlier writing code for a device needed high level programming skills, but a lot has changed now. If you know how to write code in C# you can still write code for smaller devices.

On top of this, embedded development has been further boosted with the availability of IDE?(integrated development environment) support. One example of this is .NET Micro Framework which contains a subset of .NET libraries for building embedded applications for resource constrained devices.

These emulators can also be extended for different hardware. This framework can run on small 32-bit processors and there is no requirement for a memory management unit in the processor. Instead of using a full version of an operating system, the .NET Micro Framework uses a scaled version of Common Language Runtime that sits directly on hardware with very low memory (RAM) requirements. Now the question arises why should one use this framework when there are other Microsoft embedded technologies available like Windows CE and Windows XP Embedded?

The answer is that the .NET Micro Framework uses the lowest resources as compared to the other two. This framework provides an abstraction that allows the application to be separated from the hardware platform. The code specific to the hardware platform is fed into a hardware abstraction layer (HAL) so that the .NET Micro Framework and applications can be moved to new platforms without any difficulty.

How it works
To start writing code with .NET Micro Framework one needs Visual Studio 2008 SP1 or Visual C# 2008 Express Edition plus .NET Micro Framework SDK. Download the latest version (v3.0) of SDK from http://tinyurl.com/create.php. Once this SDK is installed it would create new project type and template in VS. Along with these software components one also needs hardware for which you are writing embedded code along with SDK. Even if you don't have any hardware you can install SDK for a particular hardware.

The SDKs also include hardware emulators making it possible to write code for a particular hardware even if you don't have any hardware with you. To download SDKs for Tahoe board visit http://tinyurl.com/y9vcjeu and download 'TahoeSDK-20081119.msi' file by clicking on 'Tahoe SDK V3.0' under 'Device Solutions SDK'. In this sample implementation we are using VS 2008 SP1. Start with creating a new project with 'Project Type' as 'Micro Framework' and 'Template' as 'Windows Application'(MFWindowApplication2). Once you have created an application, you can run it to get sample output on Windows emulator. Instead of this output if you want to display your own message on an emulator, replace the content of your 'Program.cs' file with the following code:

using Microsoft.SPOT;

using Microsoft.SPOT.Presentation;

using Microsoft.SPOT.Presentation.Media;

using Microsoft.SPOT.Presentation.Controls;

using MFWindowApplication2;

namespace MFWindowsApplication2

{

public class Program : Application

{

public static void Main()

{

Application myApplication = new Program();

Window myWindow = new MainWindow();

myApplication.Run(myWindow);

}

}

public class MainWindow : Window

{

public MainWindow()

{

this.Left = 0;

this.Top = 0;

this.Width = SystemMetrics.ScreenWidth;

 this.Height = SystemMetrics.ScreenHeight;

this.Background = new SolidColorBrush((Color)0x0000FF);

Font F = Resources.GetFont(Resources.FontResources.small);

UIElement control = new Text(F,"This is our first .NET Framework Application");

control.HorizontalAlignment = HorizontalAlignment.Center;

control.VerticalAlignment = VerticalAlignment.Center;

this.Child = control;

}

}

}

In this sample code we are changing background color of given display to a different color plus we are writing a custom message at the center. If you want to use the same application and check the output on different hardware (Tahoe in our case), simply right click on 'MFWindowApplication2' in the 'Solution Explorer' window and go to properties. Now select '.NET Micro Framework' from the right column and select 'Emulator' under 'Transport' and 'TahoeEmulator' under 'Device'. However, if you have the actual device then simply connect it to your machine and select it from list of devices.