Current day of Week. Day of the Week.
Discrete Tag: 7 states.
State 0: Sun.
State 1: Mon.
State 2: Tue.
State 3: Wed.
State 4: Thr.
State 5: Fri.
State 6: Sat.
Similar to %TTMWDAY and %ATMWDAY. See also %ATMMDAY, %ATMYDAY, TM_Day.