First calculator with "textbook" input/output?

[BillBee]

(08-03-2021 04:32 PM)Dave Britten Wrote:  What was the first handheld calculator to feature "textbook"-style input and output? (Sometimes referred to as pretty print, math input, etc.) The HP 48S/SX is possibly the first, by way of having the equation writer, though this isn't the primary method of calculating - that job more often goes to the stack.

There was the Sharp EL-9200 and EL-9300, which some web sites claim came out in 1995, but I know I had an EL-9200 sometime in 1993 or 1994. This, and all subsequent Sharp graphing calculators use textbook input and output as the primary method of entering calculations on the main calculation screen. (Though you can disable it and use a simple linear entry method if you wish - textbook input was kind of sluggish on the old models, although the keyboard was buffered so you could type ahead.)

I don't think Casio had textbook I/O until the fx-9860G around the mid 2000s, and TI added it to the TI-83 Plus at some point in its firmware update history.

Anything else predating the HP 48 and Sharp EL-9200/9300 that I'm overlooking?

Hi Dave,

Would the 28C's solver method of entry qualify? It predates the 48 series IIRC.

-B