My third book is released! Learn what you'll need to know in order to become an embedded engineer.

Check out my second book; learn practical stuff about building robots and control systems around Linux PCs and the Atmel AVR.

My first book gives you all the intro you need on developing 32-bit embedded systems on a hobbyist budget.

products:

Polyceph Mk.I

Click the thumbnails for larger versions. For artwork and editable schematic see below.

Polyceph Mk.I is a development board for several different microcontrollers and sensors. It is being developed for two primary purposes:

As a basis for small projects that I am occasionally called upon to build for myself or other people.
To be used as a platform for the example circuits and code in my upcoming (fourth) book on embedded engineering.

"Polyceph" is short for "polycephalic"; i.e. possessing multiple heads, and that's really the primary characteristic of this board. It allows you to develop applications for one of four CPU familes; Atmel AVR mega64/mega128, mega48/88/168, Texas Instruments MSP430F20xx, and low-power mixed-signal Cygnal 8051 variants.

This board is designed to fit in a Hammond Manufacturing p/n 1591ESBK polystyrene box (Digi-Key p/n HM106-ND) with a small free space for batteries.

Peripherals of interest include: various power supply options, two pressure sensors, a 2D accelerometer, temperature sensor, real-time clock, SD/MMC card slot, and an uncommitted SOIC14 op-amp area that can be used to breadboard assorted filter circuits. As far as I intend to use the board, this area is really meant for impedance matching, but the pads around this chip will also allow you to build some simple filters.

The layout is now complete; click here to download the schematic and PCB files in EAGLE format. I have placed a small order of boards for my own needs and for a few colleagues.

Important: I cannot sell these boards, so don't ask.

If you want to know why, here's the reason: It is more or less impossible to operate a small side business in New York City. The laws surrounding sale of tangible goods are obviously structured for people who intend to make a fulltime business of such sales; in order to gear up to sell $10 worth of merchandise on the Internet, I would have to negotiate a quagmire of zoning issues, tax administration (vast stacks of sales tax paperwork to be filed quarterly) and other bureaucratic nonsense. Some of these issues require physically visiting the county clerk's office and begging for paperwork. Also observe that the kind and wise government of New York City benevolently charges yet another 4% income tax - on top of the separate city personal income tax, state income tax and federal income tax - on unincorporated businesses operating within the city. Absent these issues, I could probably sell these boards for about $6 each. Given that I would need to hire an accountant, lawyer and keep up with all manner of paperwork, plus the additional income taxes, the cheapest I could sell them for is about $30 (plus New York City sales tax of 8.25%). Hence I encourage you to download the source files and use the PCB house of your choice to get boards made. I hope you live somewhere that doesn't seem like a Jonathan Swift novel.

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