Well, so far one person (Kalle Pihlajasaari ) has solved this problem - and in a disgustingly short time, too! And he got the bonus question right! Andy (not the other one) gave up :%( - he blamed it on lack of sleep. I'll add some hints; both components are carbon-based, as is the input source. f(0) == f(max) == 0. And to the stuffed-shirts; remember Dr. Dobbs Journal of Computer Calisthenics and Orthodontia? Maybe we should rename this list Dr. PIC's Microcontrollers and Neurosurgery. Cheers. > Here's a PIC-related brainteaser, just to add fuel to the fire; > > A device contains only two off-the-shelf components, is powered from > an external constant-voltage supply, and has an input-output transfer > function that looks like the first 180 degrees of a sine wave. The > output units are volts. > > What are the input units, and how many digits are required to express > the full input range? > > Bonus question - why is this PIC-related? -- Clyde Smith-Stubbs | HI-TECH Software, | Voice: +61 7 3354 2411 clyde@hitech.com.au | P.O. Box 103, Alderley, | Fax: +61 7 3354 2422 http://www.hitech.com.au | QLD, 4051, AUSTRALIA. | --------------------------------------------------------------------------- For info on the World's best C cross compilers for embedded systems, point your WWW browser at http://www.hitech.com.au, or email info@hitech.com.au