Mars calculations derived from Formulae from Allison, M., and M. McEwen 2000. A post-Pathfinder evaluation of aerocentric solar coordinates with improved timing recipes for Mars seasonal/diurnal climate studies. Planet. Space Sci. 48, 215-235. and NASA's' Mars24 Algorithm and Worked Examples.
The following programs were used for verification: Mars24 written by Dr. Robert B. Schmunk at NASA Goddard Institute for Space Studies http://www.giss.nasa.gov/tools/mars24/ and Mars Clock by James Tauber at http://jtauber.github.io/mars-clock/.
Thanks also to Andrea, a fellow Pebbler, for the Mars Watchface idea.