Commodore VIC-20 User Manual page 161

where:
Chapter 4: Advanced BASIC Programming
147
TIMES
=
"hhmmss"
hh is the hour between 0 and 23
mm is the minutes between 0 and 59
ss is the seconds between 0 and 59
For hh, enter the hour of the day from 00 (12
A.M.)
to 23 (11
P.M.).
The VIC
20 computer is on a 24-hour cycle so that you can distinguish between
A.M.
and
P.M.
The hours from 00 to 11 designate
A.M.,
and the hours from 12 to 23
designate
P.M.,
returning to 00 at midnight. At midnight, when one 24-hour
cycle ends and another begins, hh, mm, and ss are all set to zero.
When initializing TIME$ to the actual time, type in a time a few
seconds in the future. When that actual time is reached, press the
RETURN
key to set the clock.
TIMEf"
1
129159"
Accessing the Clock
To retrieve the time, type the following in immediate mode:
?TIME*
The computer will display the time in hhmmss format.
?TIME$
129290
The VIC 20 computer clock keeps time until it is turned off. The clock
must be reset when the computer is turned on again.
Real-Time Clock Operation
The VIC 20 computer actually keeps track of time injiffies. A jiffy is
1/60 of a second. TIME, or TI, is a reserved numeric variable that automati-
cally increments every 1/60 of a second. TIME is set to zero on start-up and
is set back to zero after 51,839,999 jiffies. TIME$ is a string variable that is
generated from TIME. When TIME$ is called, the computer displays time
in hours, minutes, and seconds (hhmmss); that is, it converts jiffy time to real
time.
Notice that TIME$ and TI$ are not the string representations of TIME