If you follow the world of small microcontrollers you will certainly be familiar with the usual fare of Atmel, ARM Cortex, PIC, and others. But these aren’t the smallest or cheapest devices, below them is an entire category of grain-of-dust microcontrollers with minimal capabilities and at rock bottom prices. Maybe the most well known are the Padauk series of chips, whose PIC12-like architecture can be had for literal pennies. These are the famous 3 cent microcontrollers, but despite their fame they have a bit of a reputation in our community for being difficult to work with. [Ben Lim] dispels some of those ideas, by Padauk-enabling a motor and encoder from a printer to make a three cent motor controller.
The Padauk doesn’t have on-chip peripherals such as SPI, instead its IDE provides bit-banging code to do the job. This and some PID motor controller code makes for a straightforward task on the little chip, and with the help of a probably considerably more expensive MAX14870 it can drive the motor. For the curious, the code can be found in a Git Hub repository. There may be more accomplished motor controllers to be found, but we doubt you’ll find one with a cheaper microcontroller.
Want to know what the fuss is about with the Padauk? Our colleague [Maya Posch] has you covered.