(55) Programming Challenge

[Steve Simpkin]

(11-27-2024 10:31 AM)Gamo Wrote:  To me I think the HP-55 is the most difficult calculator to program because this particular model doesn't have FRAC, INT, RAN#, ABS and most key stroke takes extra line steps that make program fill up the maximum of 49 programming steps easily most of time.
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Yes, the HP-55 was a great product for a brief time in 1975. It allowed you to have a programmable HP calculator for about 1/2 the price of a HP-65. Of course 7 months later the HP-25 came out at half the price of the HP-55.

While the HP-25 lacked Linear Regression, Factorial, a timer, metric/english conversions and had 12 fewer memory locations, it was more compact, had ENG notation, storage arithmetic, FRAC, INT, ABS, PAUSE, more tests and most importantly, fully merged program steps. At $195 it probably greatly reduced the sales of the HP-55. The price of the HP-55 was dropped to $335 about 2 months later.
https://www.hpmuseum.org/cgi-bin/compare...ne&diff=ON