To Start, Stop,And Reset - HP -01 Owner's Manual

TO START, STOP, AND RESTART. Having set the timer or stopwatch, press @ to start it.
If you entered a non-zero time, the timer counts down, sounds an alarm when it reaches zero,
then immediately starts counting up as the stopwatch function takes over.
When the stopwatch is started, it counts up in hundredths of seconds to a maximum of 24
hours. Then it automatically resets to zero and starts counting up again.
Press @ again to stop the timer or stopwatch.
Pressing . again restarts it from the previous stopping point.
Press Display
09.0
oe:oo.og
Timer set to 2 minutes.
e
01:59.99
Start timer.
Timer/Stopwatch 25