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Difference between + key and += key - Karl-Ludwig Butte - 10-28-2022 09:42 AM
Dear All,
I noticed that some early pocket calculator, like e.g. HP-10 (+= key only), Privileg Super 2002, Multiplus or some commercial desktop calculators, have a += key and a -= key, while most other machines have seperate +, - and = keys.
Does anybody know the functional and technical differences and the background reason why the alternatives += and -= keys were developed?
Thank you very much in advance.
Best regards
Karl
RE: Difference between + key and += key - Nigel (UK) - 10-28-2022 12:34 PM
This doesn’t fully answer your question, but it is a nice explanation of “adding machine logic”:
https://www.hpmuseum.org/hp10.htm
Nigel (UK)
RE: Difference between + key and += key - Thomas Klemm - 10-29-2022 09:52 AM
For details, see the examples in the HP-10 Owner's Handbook.
RE: Difference between + key and += key - Karl-Ludwig Butte - 10-30-2022 08:56 AM
Thank you a lot for your answers, Nigel and Thomas.
Best regards
Karl