Keyboard Layout HP-41C and early models

[Massimo Gnerucci]

(06-14-2019 01:49 PM)Andres Wrote:  The numeric keypad layout of the IBM PC and derivatives (and, to a lesser extent, video "dumb terminals") may have had an influence. After 1981, people all around the world got familiar with the "operation keys on the right column, plus key on the bottom" layout of such alphanumeric keyboards.

In '81 you had IBM 327x (not even dumb) terminal keyboards without numeric keys on the right side, just arrows and insert, delete, control keys...
IBM model F keyboard had numeric keypad on the right with a small "-" and a taller (3x) "+" under it; "-" and "*" where on the main keyboard plane. The "*" also on the left of numpad. Function keys on the left side.

It was model M (1984) "enhanced" keyboard that standardized the current setup, with numeric and operation keys on the right side and function keys on top.