The 82182A Time Module
The time module added a real-time clock. The clock allowed you to use the actual time in your programs.
You could also define alarms that triggered calls to user programs. The alarms were able to switch the calculator on, so it was possible to create programs that executed at some point during the day, then switched the calculator off until the next alarm. As the HP-41 was often used as data-gathering device in labs, this allowed the calculator to read data from monitored devices at specific times every day, without having to run in between the readings (thus saving battery capacity).
The HP-41CX had the time module built-in.
Read more about this topic: HP-41 Extension Module
Famous quotes containing the word time:
“And what avails it that science has come to treat space and time as simply forms of thought, and the material world as hypothetical, and withal our pretension of property and even of self-hood are fading with the rest, if, at last, even our thoughts are not finalities, but the incessant flowing and ascension reach these also, and each thought which yesterday was a finality, to-day is yielding to a larger generalization?”
—Ralph Waldo Emerson (1803–1882)