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PORTING MICROC/OS-II TO THE TS-2800 EMBEDDED PC

by Robert Bowen

Start ý Where to Begin ý Development Tools ý Booting the TS-2800 ý Installing the MicroC/OS-II ý Creating a MicroC/OS-II Application ý Creating the GUI ý Future Goals ý Sources and PDF

Okay, I have a confession to make. I have been designing embedded systems for over 10 years, and I have never used an off-the-shelf single board computer (SBC) or real-time kernel in any of my projects. Why? My designs are simple. They donýt warrant the luxury of an RTOS. I donýt have time to learn how a kernel works. For years, Iýve been struggling to overcome these inadequate excuses.

The 8751 microcontroller has been the heart of all my projects. If I needed an RS-232 interface, I added the popular MAX232 IC. Need more digital I/Os? No problem! Toss in your favorite flavor 8255 programmable peripheral interface (PPI).

My firmware is written using the super-loop concept. During powerup, the processor performs the usual housekeeping and settles into Idle mode. When an interrupt occurs, the processor executes the command received and the process starts again.

So, whatýs the problem? My designs started getting more complicated. Users wanted network capability, complex I/O such as servo motor controllers, and high-speed data acquisition. Had I incorporated a single board computer that supported stackable expansion plug-ins, upgrading would have been trivial. Additionally, I found that my designs were not reusable from system to system. And, my firmware lacked the advantages of a real-time kernel.

My goal was to develop a new design platform, using an off-the-shelf embedded PC (ePC) and a real-time multitasking kernel. I took advantage of any open-source programming tools and software and used the Internet to search for a low-cost ePC and real-time executive.

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