Interfacing Electronics, Motors, and Microcontrollers This weekend, I finally got out the soldering iron and put together a 4-bit controller to run a stepper motor using an 8052 microcontroller.

I used an off-the-shelf motor (28BYJ-48) and driver board (ULN2003) for £1.32, a 5V DC-to-DC regulator (LM7805, £0.07) to generate stable digital voltage levels from a 9V battery, and four latching push-button switches (£0.08ea) to generate the 4-bit digital logic hi/lo signals. This shows how a repeating pattern of 8 pulses (1000, 1100, 0100, 0110, 0010, 0011, 0001, 1001, ...) turns the motor ever so slowly. To get some rotational speed, we need the help of the 8052 microcontroller to drive the I/O lines faster than our fingers can fly.

Total cost? Less than £2.50. (£1.63 above + misc. supplies incl. small solderless breadboard £0.36, PCB £0.11, hookup wires, misc. resistors and caps, low current LEDs). Traversing the technology chain? Priceless!

To see this and other low-cost electronics projects that have high impact on kids perception of technology and their own abilities to create, click-through to the article "Electronics in the Junior School: Gateway to Technology".

What next? ... The plan is to port Frank Sergeant's "3-instruction Forth" [3] to the 8052 to allow near real-time modification of the behavior of the motors in response to user signals. Watch this space.

Article & Project Gallery:
Electronics in the Junior School: Gateway to Technology, Nov 2018
http://mathscitech.org/articles/exploring-electronics

Electronics Page DIY Supply Guide (UK)
http://mathscitech.org/articles/electronics

[3] Frank Sergeant, 1991, A 3-Instruction Forth for Embedded Systems Work
http://pygmy.utoh.org/3ins4th.html


Happy 2019 to friends and collaborators
+Bernd Paysan +Arran Holloway +Asa Packer +Michael Wolfrom +Todd Schoepflin +Keith Johnson +Steve Maurer +Natalia Burina +Carol Ouellette +Adrian Harris Crowne +Garett Newman +Yul Kwon +Bob McClure +Shafiq Shariff +Zakir Kassam +Leon Maurer +Leo Brodie +Ashley Feniello +Mark Blooman +Jason Bennett +Karl Knaub +Simon Raper +Moira Kelly +Alan Clements +Stefan Cygon +Shakeel Mohamed +Viktor Toth