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Hewlett Packard HP-97

• Type: Programmable RPN Electronic Calculator
• Size:
• Serial number:
• Date of Manufacture: March 1978

The desktop version of the HP-67, the 97 included all the 67's functions and the magnetic card reader and added a thermal printer.

The 67 had trebly-overloaded keys, like the HP-34C, but the extra real estate on the 97's face allowed it to get away with a single shift key.

The 67/97 were the first calculators with fully merged keycodes. This means that a two-keystroke instruction required a single memory location; previous calculators required a memory location for each keystroke.

On the 97 there are two key arrays. The left-side array has keycodes with positive numbers, the right-hand side has negative numbers.

Constant memory is not available on the 67/97, but programs and registers can be recorded to magnetic cards.

(NOTE TO SELF: rebuild the card reader)