The HP-18C is a Hewlett-Packard business calculator which was quickly followed by the very similar but greatly improved HP-19B. The HP-18C is HP's first RPL-based calculator internally,[1] even though this was not visible on user-level in this non user-programmable model. The user has a solver (another HP first) available, but only had about 1.5 KB of continuous memory available to store equations.

An HP-18C in the state used for operating it. When not in use or for transport, it can be folded together due to its clamshell design, so that its width becomes half of what it is in the image.

The calculator has many functions buried in a menu structure. The clamshell design is fairly robust, but the battery door is the shortcoming of this whole line; 18C, 19B, and 28C/S models.

The HP-18C was introduced in June 1986.[1]

See also

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References

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  1. ^ a b Wickes, William C. (1988-10-01) [14–18 June 1988]. Forsely, Lawrence P. (ed.). RPL: A Mathematical Control Language. Proceedings of the 1988 Rochester Forth Conference: Programming Environments. Vol. 8. Rochester, New York, USA: Institute for Applied Forth Research, Inc., University of Rochester. pp. 27–32. ISBN 978-0-91459308-9. OCLC 839704944. Several existing operating systems and languages were considered, but none could meet all of the design objectives. A new system was therefore developed, which merges the threaded interpretation of Forth with the functional approach of Lisp. The resulting operating system, known unofficially as RPL (for Reverse-Polish Lisp), made its first public appearance in June of 1986 in the HP-18C Business Consultant calculator. (NB. This title is often cited as "RPL: A Mathematics Control Language". An excerpt is available at: RPLMan from Goodies Disk 4zip file)

Further reading

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