% TTCREATEPERIODICTIMER   Create a periodic timer and associate%                         an interrupt handler with the timer.%%  Usage: ttCreatePeriodicTimer(timername, start, period, handlername)%%  Inputs:%    timername    Name of the timer, must be unique.%    start        The time for the first expiry of the timer.%    period       The period of the timer.%    handlername  Name of the interrupt handler to be associated %                 with the timer.%       % See also TTCREATEINTERRUPTHANDLER, TTCREATETIMER, TTREMOVETIMER%%       TrueTime, Version 1.4%       Copyright (c) 2006%       Martin Ohlin, Dan Henriksson and Anton Cervin%       Department of Automatic Control, LTH%       Lund University, Sweden