Blast from the past—Popular Science article.

[Steve Simpkin]

Very cool article. I love how it mentions the unreleased National Semiconductor NS-7100 programmable calculator. Announced In 1976, this unusual model featured 240 steps of built-in non-volatile program memory, 32 non-volatile data memories, support for semiconductor memory expansion modules, pre-programmed software modules and peripherals. This calculator would have been ahead of its time in technology in 1976. This unusual model was scheduled to be released as early as Jan 1977.
It never happened.

Prototypes were made and I know of several people that were able to play with one so this was not just vaporware. I have not been able to find a definite reason why National Semiconductor (NS) cancelled the project. Non-volatile memory in hand held calculators was cutting edge technology in 1976. The worlds first programmable calculator with non-volatile memory, the HP-25C, was only introduced in Jul 1976 so perhaps NS was having technical issues. I suspect it was more likely due to the drop in calculator pricing that was occurring during this time. When NS started this project, high end programmable calculators were still very expensive, the HP-65 was selling for almost $800. At an introductory price of $300 the NS-7100 with its advanced features would have been very attractive and profitable. By the time 1977 rolled around, prices for these advanced models was dropping rapidly. The TI-58 introduced in July 1977 had twice the memory, software modules and a lot more functions for only about $125. This was probably the nail in the coffin for the NS-7100.

If anyone can find out more information on the fascinating model, I would love to see it.