Fullscreen digital clock for DOS 6.22?

An old school PC needs old school tools. Borland Turbo C was a popular early C development package. The tools have been re-released as freeware. You can download it from the Embarcadero site at http://edn.embarcadero.com/article/20841.

This is not a full screen digital clock but is pretty cool: http://sourceforge.net/projects/lcars24/

Perhaps DOS Clock would work: http://www.thangorodrim.de/software/dos_clock/index.html