HP 50 as a stop watch.



I wish to use the HP50 as a stop watch to time road runners in a race. It should not be difficult to program to do this.

The only problem is that the calculator can go to sleep if there is a big gap between runners. This means that you could miss time a runner.

I have searched for a internal flag that might control the calculator sleeping, but I have had no success.

Does anyone know how to stop the HP from sleeping during a race?


have you tried with the internal variable TOFF??

you can define an idle time before variable STARTOFF is executed.

Remember 1second = 8192 TICKS


Edited: 9 Sept 2009, 8:20 a.m.


I must be missing something. I have tried TOFF just by keying it in but get no response. If I do a seach in the electronic manual on TOFF nothing comes up. How do you get access to this command?

The variable STARTOFF is one of your variables?


Store a hexadecimal number as TOFF in HOME. It represents tics (8192/sec)

So #8192d * 60 * min will set a new off time. As for a stopwatch, look here: http://www.software49g.gmxhome.de/EnglishSeite01.htm#SWC


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