HP -01 Owner's Manual page 90

Operational Description 88
Digit Position
12/3/4/5/6/7/8/9
Time Interval Entry and Display Data
Minimum Entry 00 : 00 0 1 H = hours
Maximum Entry 9 9 9 9 9 59 M = minutes
Ijisplay = 100 Hours HHHHH M M S = seconds
Display 1 - <100 Hours H H M M S S C = hundredths of seconds
Display <1 Hour M M S S c C
Time of Day Entry and Display Data
Minimum Entry 00 : 00 -0 12- or 24-hour format.
Maximum Entry 23 :59 :59