I needed a place to put schematics, printed circuit board artwork, and S-basic library's and drivers, as I discover them, and learn how they work, and this is it. I have learned a lot from Karl Lunts web page http://www.seanet.com/~karllunt/ he is the Author of S-Basic, a Basic Language compiler that allows you to write programs in any editor for the Motorola 68HC11 Microcontroller (Fun,Fun,Fun). The S-Basic compiler is available from Karl's home page as a free download, and I do recommend you get it. The circuit boards I have been using with the 68HC11 are called the Botboard, and I am using version 1, it is a simple design, and use's all the capabilities of the 68HC11, the only thing it is missing is external memory, which you could add with a daughter board if you wanted too. The total cost if you buy everything is about $50.00. I didn't need to buy much, so these boards are very cost effective for me. You can get these boards at Marvin Green's web site for $4.95 a piece. http://www.rdrop.com/users/marvin/ now that's a sweet deal. Of course all the information I keep at this site will be based on the Botboard1, but you can easily apply this information to other Microcontrollers, and PIC's. I have tried to make these boards very easy for the amature hobbyist to be able to duplicate these boards. I have included all the information for these boards in the Adobe PDF files below, schematics, artwork, parts list, and any other information that I think you might need. These boards are all one sided, and use only one drill size for the components (.039 inch). I hope you find these boards easy to make, and please give me feedback if you think I missed something, or you need help. Have fun...

-Mike

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The Botboard 1

This text borrowed from the Botboard 1 manual.
BOTBoard is a 2" X 3", single sided printed circuit board designed around the 68HC11 family of microcontrollers. On the BOTBoard, the 68HC11 is set into single chip mode, and can execute a program from its internal EEPROM or EPROM. All major I/O pins are brought to header's along with a TTL level serial port and SPI port for networking. Four connectors are dedicated to controlling hobby R/C servos, and a prototyping area is also provided. This board was designed with amateur robotics in mind, with a construction cost approximately. $20. The BOTBoard is adapted from the articles and circuits described in P.A.R.T.S , the Portland Area Robotics newsletter, describing a how to build a single chip robot. The BOTBoards layout is very generic and may be used for general experimentation and project development.

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The 5 Volt Simple Switcher

One of the first boards that I needed was some kind of regulator that would keep a clean + 5 volts D.C. going to my Botboard. If I had just used a regulator, I would be bleeding a lot of valuable power to ground. So I needed something a little more energy efficient. I settled on a National Instruments Simple Switcher chip LM2575HVM-5.0, this chip was recommended by Karl, and in fact used on one of his robots. I first made a prototype that was 3 inches in length, but worked fine. I made a second version of this board that I am using in several of my projects, and it is less then 1.2 inches by 1.9 inches. I think you will like this board, and I will put a link to the PDF file here that includes all the information necessary to make this board.

+ 5 Volt Switcher

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The Unipolar Stepper Motor Driver, and Software

The next board that I prototyped was a Stepper Motor driver made from some NPN transistors ( TIP-31 to be exact, TIP-120 can be substituted to handle more current.) . I borrowed the final stage from a schematic I found on the internet, and I put some pull-up resistor and series resistors on the front of the NPN, and from that to my Botboard. To my suprise this setup seemed to power the coils in the motor OK. To get the software to work was a little more trouble. It took several try's before I had the hang of it. But now I have made a Library include file that you can add at the top of your program, that will give you some very flexiable commands you can use in your program. You will be able to control up to four of these Stepper Motor driver boards from your Botboard. This should give you a lot of capability for your projects.

Unipolar Stepper Motor Driver Artwork

Unipolar Stepper Motor Driver Software

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