Systronix_utilities.cpp
//---------------------------< _ D A Y _ O F _ W E E K >------------------------------------------------------
//
// This code is adapted from similar code written by Martin Minow while he was at Digital Equipment Corporation.
// His code, called Today, converted system date and time to a readable format of the date and time as
// WGBH Morning Pro Musica host Robert J Lurtsema spoke it on air.
// Year, 1978 = 1978
// Month, January = 1
// Day of month, 1 = 1
//
// Returns the day of the week on which this date falls: Sunday = 0. Note, this routine is valid only for the
// Gregorian calendar.
//
< _ D A Y _ O F _ W E E K >
This code is adapted from similar code written by Martin Minow while he was at Digital Equipment Corporation.
His code, called Today, converted system date and time to a readable format of the date and time as
WGBH Morning Pro Musica host Robert J Lurtsema spoke it on air.

Returns the day of the week on which this date falls: Sunday = 0. Note, this routine is valid only for the
Gregorian calendar.
< _ D A Y _ O F _ W E E K > This code is adapted from similar code written by Martin Minow while he was at Digital Equipment Corporation . His code called Today converted system date and time to a readable format of the date and time as WGBH Morning Pro Musica host Robert J Lurtsema spoke it on air . Returns the day of the week on which this date falls : Sunday = 0 . Note this routine is valid only for the Gregorian calendar .
uint8_t Systronix_utilities::_day_of_week(uint16_t year, uint8_t month, uint8_t day)
	{
	uint16_t yearfactor;
	yearfactor = year + (month - 14)/12;
	return (uint8_t)(( (13 * (month + 10 - (month + 10)/13*12) - 1)/5
		+ day + 77 + 5 * (yearfactor % 100)/4
		+ yearfactor / 400
		- yearfactor / 100 * 2) % 7);
	}
uint8_t Systronix_utilities :: _day_of_week ( uint16_t year , uint8_t month , uint8_t day ) { uint16_t yearfactor ; yearfactor = year + ( month - 14 ) / 12 ; return ( uint8_t ) ( ( ( 13 * ( month + 10 - ( month + 10 ) / 13 * 12 ) - 1 ) / 5 + day + 77 + 5 * ( yearfactor % 100 ) / 4 + yearfactor / 400 - yearfactor / 100 * 2 ) % 7 ) ; }
< _ D A Y _ O F _ W E E K >
This code is adapted from similar code written by Martin Minow while he was at Digital Equipment Corporation.
< _ D A Y _ O F _ W E E K > This code is adapted from similar code written by Martin Minow while he was at Digital Equipment Corporation .