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DISPENSING THE GOODS, EMBEDDED STYLE

by Todd Rytting

Start ý For Exampleý ý Development ý C/C++ ý Visual Basic ý Keep Your Change ý Sources and PDF

DEVELOPMENT

If youýre not familiar with EMIT, you might want to take a look at the Working with EMIT sidebar before you start reading this section. Letýs deal with the process that most embedded engineers hateýthe GUI. With EMIT, the bulk of your effort goes into what you do best (i.e., designing and building embedded devices). Once emMicro is integrated at the embedded level, everything else is a piece of cake. The tools that are available for creating user interfaces are sophisticated and powerful, allowing rapid development of the client applications.

The examples shown below can be performed with the EMIT SDK Eval and, for the hardware, you can use your own 8- or 16-bit demonstration board or the SDK reference board simulator (also included in the SDK Eval).

WEB BROWSERS

Controlling a device with a web browser is the first thing that most people think of when an Internet-enabled device is mentioned. Browsers and the Internet go together. EMITýs solution to browser-based user interfaces for embedded devices uses existing rapid application development tools created for building Java applets. A 30-day trial version of Visual Café is included with the SDK to help get you up and running.

Several browser-based user interfaces are included with the EMIT SDK. Letýs assume you already have the EMIT software and the SDK reference board (or the Virtual SDK board) installed and configured as described in the documentation. If you followed the instructions (I know thatýs a stretch), youýve already seen and operated a user interface that looks like Photo 2.

Photo 2ýA browser-based user interface created with Visual Café.

This embedded application demonstration controls the brightness of two onboard LEDs with a rotary pot. It can also datalog into the EEPROM and play back the stored data into one of the LEDs. On the user interface, all the knobs, LED bar graphs, and X/Y graphs are emObjects provided with EMIT. If you want to experiment with this user interface, the Visual Café project is contained in your VisualCafeWDE\Projects\sdk25 subdirectory. The SDK also includes other user interfaces to serve as templates and examples.