Minimal Key Calculator

[BruceH]

(03-13-2015 05:59 PM)Thomas Radtke Wrote:  But Paul wrote 'none', which is correctly none (not one) key .

Actually, "none" is not a contraction of "not one". Explanation.

[Garth Wilson]

I designed a commercial product in the late 1980's that used a gray-code rotary switch and a pair of buttons, per the instructions given me. The knob worked similar to the old Dymo label makers where you'd turn the dial until you got to the character you wanted and then press it into the pastic label tape. Turn the gray-code switch and the choices would scroll through a character position in the LCD (including choices for backspace, exit, etc.), then press the "Enter" key. There was also a "Cancel" key, and pressing both together was "Help." Later I did it with only keys, an up-arrow, down-arrow, Enter/Yes/Continue, Cancel/No/Exit, and Help/Menu. A friend uses a piece of equipment at his work that uses the knob with a pushbutton behind it (so you can rotate and press the knob), so everything is in one control. The virtue, I suppose, is in not requiring so much panel area in situations where you don't spend much time operating it. The rotary switch is expensive though, and certainly takes more depth behind and in front of the panel. For something like the calculator, I don't think there's really a virtue in minimizing the key count.

[rprosperi]

(03-13-2015 09:31 PM)Didier Lachieze Wrote:  There was one overlay for sale on ebay.de some weeks ago.
Here is a picture from this auction: Laitram XQ2.
You can also find the Laitram manual on TAS.

(03-13-2015 09:36 PM)Massimo Gnerucci Wrote:  Laitram vs HP

Thank you both, was not aware of this ROM or of the specifics of the lawsuit. I did know Dave Conklin who at the time had recently founded Tripod Data Systems with Bernie Musch and other ex-HP folks, and there was reference to the lawsuit, but I never asked for details. Very interesting history. Have either of you tried the ROM to see how well it works?

[Marcus von Cube]

(03-13-2015 10:25 PM)BruceH Wrote:  

(03-13-2015 05:59 PM)Thomas Radtke Wrote:  But Paul wrote 'none', which is correctly none (not one) key .

Actually, "none" is not a contraction of "not one". Explanation.

From the above link:

Quote:Our modern form none comes from the Old English nan

So it is actually "not a number" and thus can neither be singular nor plural.

[Eddie W. Shore]

(03-13-2015 10:20 AM)BartDB Wrote:  

(03-13-2015 08:17 AM)Gerald H Wrote:  In another thread the question of unnecessary functions & redundant keys is raised:

http://www.hpmuseum.org/forum/thread-3345.html

What could be the least number of keys needed to reproduce all the functions of, say, the HP 35S keyboard?

If you were happy with a purely binary calculator, only two number keys would be required - but probably you would want to keep decimal input, so let's say you stay decimal.

Not the least number of keys, but what I'd be comfortable using without too many shifts & menu's. Small form factor with 23 keys:



http://pickyb.blogspot.co.uk/2014/05/pro...kcalc.html

Best regards.

I would love to have this scientific calculator.