Option explicit
Option default integer
'
const EPOCH_YR = 1970
CONST SECS_DAY = 86400
CONST SECS_HOUR = 3600
CONST SECS_MIN = 60

dim ytab1(11)=(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31)
dim monoff(11) = ( 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334)
dim daysofweek$(6) length 9 =("Sunday","Monday","Tuesday","Wednesday","Thursday","Friday", "Saturday")
dim my_year, my_month, my_day, my_hour, my_min, my_sec, my_dayno, my_dayinyear, my_timestamp
dim monthsinyear$(11) length 9 = ("January", "February", "March", "April", "May", "June" , "July", "August", "September", "October", "November", "December")
dim th$(30) length 2 = ("st","nd","rd","th","th","th","th","th","th","th","th","th","th","th","th","th","th","th","th","th","st","nd","rd","th" ,"th","th","th","th","th","th","st")
'

dim nowtime
convert_time() 'convert time$ and date$ to Unix epoch time
print format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
' what was the time and date 400 days, 17 hours, 15 minutes and 22 seconds ago?
gmtime(my_timestamp-(400*SECS_DAY + 17*SECS_HOUR + 15*SECS_MIN + 22))
print format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
' what will be the time and date 200,000,000 seconds in the future?
gmtime(my_timestamp+200000000)
print format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
convert_time()
nowtime=my_timestamp
do
convert_time()
loop until my_timestamp>=nowtime+10
print "Starting programmed event @ ",format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
do
convert_time()
loop until my_timestamp>=nowtime+20
print "Stopping programmed event @ ",format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
end
'
sub convert_time() 'loads global time variables from time$ and date$
rtc gettime
my_year= val(right$(date$,4))
my_month=val(mid$(date$,4,2))
my_day=val(left$(date$,2))
my_hour=val(left$(time$,2))
my_min=val(mid$(time$,4,2))
my_sec=val(right$(time$,2))
my_timestamp=timegm(my_year, my_month, my_day, my_hour, my_min, my_sec)
daycalcs(my_timestamp)
end sub

function is_leap_year(year as integer) as integer
is_leap_year = 0
if year mod 4 = 0 then is_leap_year=1
if year mod 100 = 0 then is_leap_year=0
if year mod 400 = 0 then is_leap_year=1
end function

function leap_days(yy1 as integer, yy2 as integer)as integer
local integer y1=yy1, y2=yy2
y1=y1-1
y2=y2-1
leap_days= (y2\4 -y1\4) - (y2\100 -y1\100) + (y2\400 -y1\400)
end function

function timegm(tm_year as integer, tm_mon as integer, tm_mday as integer, tm_hour as integer, tm_min as integer, tm_sec as integer) as integer
local integer year, days, hours, minutes
year = tm_year
days = 365 * (year-1970) + leap_days(1970,year)
days=days + monoff(tm_mon-1)
if tm_mon>1 and is_leap_year(year) then days=days+1
days = days + tm_mday -1
hours = days * 24 + tm_hour
minutes = hours * 60 + tm_min
timegm = minutes * 60 + tm_sec
end function

sub daycalcs(tm_seconds as integer) 'calculate day of week and day in year
local integer year = EPOCH_YR, dayno = tm_seconds\SECS_DAY
my_dayno = (dayno + 4) mod 7
do while dayno>=yearsize(year)
dayno=dayno-yearsize(year)
year=year+1
loop
my_dayinyear=dayno
end sub

sub gmtime(tm_seconds as integer) 'calculate all parameters from the epoch time
local integer year = EPOCH_YR, dayclock = tm_seconds mod SECS_DAY, dayno = tm_seconds\SECS_DAY, tm_mon=0
my_sec = dayclock mod 60
my_min = (dayclock mod 3600) \60
my_hour = dayclock \ 3600
my_dayno = (dayno + 4) mod 7
do while dayno>=yearsize(year)
dayno=dayno-yearsize(year)
year=year+1
loop
my_year=year
my_dayinyear=dayno
do while dayno>=ytab1(tm_mon)
dayno=dayno-ytab1(tm_mon)
if tm_mon=1 and is_leap_year(year) then dayno=dayno-1
tm_mon=tm_mon+1
loop
my_month=tm_mon+1
my_day=dayno+1
end sub

function yearsize(year as integer) as integer
yearsize=365
if is_leap_year(year) then yearsize=366
end function

function format_time$() as string
format_time$=str$(my_hour,2)+":"+right$(str$(my_min+100),2)+":"+right$(str$(my_sec+100),2)
end function

secs=(Val(Left$(Time$,1)) Mod 12) * 3600 + Val(Mid$(Time$,4,2)) * 60 + Val(Right$(Time$,2))

 option base 1
 Option explicit
 Option default integer
 '
 const EPOCH_YR = 1970
 CONST SECS_DAY = 86400
 CONST SECS_HOUR = 3600
 CONST SECS_MIN = 60
 
 dim ytab1(12)=(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31)
 dim monoff(12) = ( 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334)
 dim daysofweek$(7) length 9 =("Sunday","Monday","Tuesday","Wednesday","Thursday","Friday", "Saturday")
 dim my_year, my_month, my_day, my_hour, my_min, my_sec, my_dayno, my_dayinyear, my_timestamp
 dim monthsinyear$(112) length 9 = ("January", "February", "March", "April", "May", "June" , "July", "August", "September", "October", "November", "December")
 dim th$(31) length 2 = ("st","nd","rd","th","th","th","th","th","th","th","th","th","th","th","th","th","th","th","th","th","st","nd","rd","th" ,"th","th","th","th","th","th","st")
 '
 
 dim nowtime
 convert_time() 'convert time$ and date$ to Unix epoch time
 print format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
 ' what was the time and date 400 days, 17 hours, 15 minutes and 22 seconds ago?
 gmtime(my_timestamp-(400*SECS_DAY + 17*SECS_HOUR + 15*SECS_MIN + 22))
 print format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
 ' what will be the time and date 200,000,000 seconds in the future?
 gmtime(my_timestamp+200000000)
 print format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
 convert_time()
 nowtime=my_timestamp
 do
   convert_time()
 loop until my_timestamp>=nowtime+10
 print "Starting programmed event @ ",format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
 do
   convert_time()
 loop until my_timestamp>=nowtime+20
 print "Stopping programmed event @ ",format_time$()," ",daysofweek$(my_dayno), my_day,th$(my_day-1), " ", monthsinyear$(my_month-1) , " ",my_year
end
 '
sub convert_time() 'loads global time variables from time$ and date$
 rtc gettime
 my_year= val(right$(date$,4))
 my_month=val(mid$(date$,4,2))
 my_day=val(left$(date$,2))
 my_hour=val(left$(time$,2))
 my_min=val(mid$(time$,4,2))
 my_sec=val(right$(time$,2))
 my_timestamp=timegm(my_year, my_month, my_day, my_hour, my_min, my_sec)
 daycalcs(my_timestamp)
end sub
 
function is_leap_year(year as integer) as integer
 is_leap_year = 0
 if year mod 4 = 0 then is_leap_year=1
 if year mod 100 = 0 then is_leap_year=0
 if year mod 400 = 0 then is_leap_year=1
end function
 
function leap_days(yy1 as integer, yy2 as integer)as integer
 local integer y1=yy1, y2=yy2
 y1=y1-1
 y2=y2-1
 leap_days= (y2\4 -y1\4) - (y2\100 -y1\100) + (y2\400 -y1\400)
end function
 
function timegm(tm_year as integer, tm_mon as integer, tm_mday as integer, tm_hour as integer, tm_min as integer, tm_sec as integer) as integer
 local integer year, days, hours, minutes
 year = tm_year
 days = 365 * (year-1970) + leap_days(1970,year)
 days=days + monoff(tm_mon-1)
 if tm_mon>1 and is_leap_year(year) then days=days+1
 days = days + tm_mday -1
 hours = days * 24 + tm_hour
 minutes = hours * 60 + tm_min
 timegm = minutes * 60 + tm_sec
end function
 
sub daycalcs(tm_seconds as integer) 'calculate day of week and day in year
 local integer year = EPOCH_YR, dayno = tm_seconds\SECS_DAY
 my_dayno = (dayno + 4) mod 7
 do while dayno>=yearsize(year)
   dayno=dayno-yearsize(year)
   year=year+1
 loop
 my_dayinyear=dayno
end sub
 
sub gmtime(tm_seconds as integer) 'calculate all parameters from the epoch time
 local integer year = EPOCH_YR, dayclock = tm_seconds mod SECS_DAY, dayno = tm_seconds\SECS_DAY, tm_mon=1
 my_sec = dayclock mod 60
 my_min = (dayclock mod 3600) \60
 my_hour = dayclock \ 3600
 my_dayno = (dayno + 4) mod 7
 do while dayno>=yearsize(year)
   dayno=dayno-yearsize(year)
   year=year+1
 loop
 my_year=year
 my_dayinyear=dayno
 do while dayno>=ytab1(tm_mon)
   dayno=dayno-ytab1(tm_mon)
   if tm_mon=1 and is_leap_year(year) then dayno=dayno-1
   tm_mon=tm_mon+1
 loop
 my_month=tm_mon+1
 my_day=dayno+1
end sub
 
function yearsize(year as integer) as integer
 yearsize=365
 if is_leap_year(year) then yearsize=366
end function
 
function format_time$() as string
 format_time$=str$(my_hour,2)+":"+right$(str$(my_min+100),2)+":"+right$(str$(my_sec+100),2)
end function