So far the hp41cl doesn't provide a clock to be used as time module, and it requires a working one to be able to function as stopwatch or alarm clock (or launching programs at a defined time)
However, the hp41cl "raw" provides all the time-related calculating functions of the time module: days difference between two dates, date calculations, etc. So, if you don't want the above clock features, you can live without it (and why would you want them when you have a smartphone?)
There are always those that would like to have the full Monty (never better said when referring to Monte’s development), and then you may want to have the time module too. Or, you have interfaced your hp41c with other items, and then you need to launch programs at a determined time intervals.
I once did that, when I connected a HP3468A HP-IL multimeter to the HP41CL to check what was the voltage in my weekend cabin during an extended period of a week. Then it was grabbing data every half hour for the whole Monday to Friday we’re not there.
Other uses that we’ve seen are:
- use it in conjunction with astronomical programs, to better direct your telescope.
- Use it during flight to calculate fuel consumption rates, direction drift on side winds during time periods, etc.
As always, here is no reason this couldn't be done with a smartphone - but if you don't have the program that does what you want, then the easily programmable HP 41CL can come to the rescue nicely.