H Some Common Unit Conversions
MiLLennium GPSCard SW Version 4.503/4.52 Command Descriptions Manual Rev 2 243
H.6 GPS TIME OF WEEK TO CALENDAR DAY (EXAMPLE)
511200 seconds Day 511200 / 86400 seconds per day = 5.916666667 days
Hour .916666667 x 86400 / 3600 seconds per hour = 22.0000 hours
Minute .000 x 3600 / 60 seconds per minute = 0.000 minutes
Second .000 x 60 = 0.00 seconds
Day 5 (Thursday) + 22 hours, 0 minutes, 0 seconds into Friday.
H.6.1 Calendar Date to GPS Time (e.g. 13:30 hours, January 28, 2005)
Days from January 6, 1980 to January 28, 2005 = 6 years x 365 days /year = 9125 days
Add one day for each leap year (a year which is divisible by 4 but not by 100 unless it is divisible by 400;
every 100 years a leap year is skipped) 7 days
Days into 2005 (28th is not finished) 27 days
Total days 9159 days
Deduct 5 days: Jan. 1 through 5, 1980 9154 days
GPS Week: 9154 x 86400 seconds per day = 790905600 seconds/ 604800 sec per week = 785
Seconds into week 6th day: 13.5 hrs x 3600 sec/hr 48600 seconds
GPS time of week: Week 1307, 48600 second