stopwatch features on calculators

[Steve Simpkin]

Here is a clock (or timer) program for the HP-25. It has a resolution of approximately 1 second and can be made fairly accurate by modifying the value stored in register 0. It could probably be adapted to work on any HP programmable model that has a PAUSE function (that lasts approximately 1 second).

Clock Program (HP-25):
01 RCL 0
02 STO+1
03 RCL 1
04 -->H.MS
05 PAUSE
06 GTO 01


Setup:
FIX 4

0.0001 (adjust this number up or down to provide an average of 1 second accuracy)
-->H
STO 0

(for a clock, enter the current time as HH.MMSS, or enter 0 for a timer)
-->H
STO 1

GTO 00
R/S to start or stop