Return the current system date.

On return:

%1 is the year.

%2 high byte is the month.

%2 low byte is the day.

%3 if provided, is the day of the week. 0=Sunday, 1=Monday...

Example:

    GetSysDate CX, DX     ; get the date
    GetSysDate CX, DX, AX ; get the date and day of the week

See also GetSysTime