The code name "Kitty Hawk" combines "Kitty" to show this is a member of the "Topcat" family of calculators with "Hawk" to show the relationship with the HP-67 whose codename was "Hawkeye".

Programs written for the HP-67 and the HP-97 are fully interchangeable - a magnetic card written on one model can be read by the other. To make this possible, four printing commands on the HP-97 had non-printing equivalents on the HP-67, as mentioned in the history article describing the HP-67. A fifth command, PRINT:[PRGM] had no equivalent on the HP-67, but it was not programmable so this did not affect the compatibility of programs saved on magnetic cards.

Like the HP-67, the HP-97 could be made to store "non-standard" instructions - this led to some interesting displays and printouts, but the printer could be made to overheat and burn out its printhead if such instructions were applied carelessly.

As on the HP-91, the printer could be set to one of three modes; MANual, TRACE and NORMal - the HP-95C (see separate history article) and later the HP-41 printers had the same modes.

The availability of a larger keyboard and more keys meant that the HP-97 had only one shift key, as opposed to three on the HP-67. (This use of just one yellow shift key was carried over to the HP-41; the ALPHA key could be treated as another shift key, but really it was a mode change key.)

The large keys used for common functions, the large and bright LED display, and the ease of saving programs and data on magnetic cards, made this a popular calculator - so much so that HP kept it in production for several years after the HP-41 had replaced the HP-67.

This article is part of the WMJARTS file. This file contains a series of articles written by Wlodek Mier-Jedrzejowicz and published in DATAFILE, the journal of the HPCC. The article was reproduced with permission of the author.