HP48SX

The HP48SX scientific calculator with its KERMIT data communications was released in 1990. Files could now be transferred directly, even between a supercomputer and a pocket calculator, using the simple, reliable file-transfer protocol developed at Columbia University in 1981. The success of Kermit was due to its simplicity and the demand in the computer community for data transfer between the widest possible variety of devices. These calculators were also capable of communicating together via an infrared link.

Easy transmission of data and versatile programmability using Reverse Polish Lisp (RPL) and the Saturn assembler language also led to the setting up of extensive Internet archives of public-domain software for this calculator popular among scientists. Even though the calculator was originally designed to handle algebraic equations and to perform calculations using complex-number matrices and other mathematical functions needed by scientists, inventive users have programmed all sorts of other functions for it, from Morse code to television remote control. It can even be used to run 1970s Telmac programs. A somewhat updated version, the HP48GX, is still on sale and popular among scientists.

HP48SX I/O settings (picture and calculator Harri Salminen)