Scientific Calculator Keyboard Challenge

[Eddie W. Shore]

Design the keyboard of a scientific calculator and post links to your designs as responses to this blog entry. Rules:

You have only 25 keys to work with. That's it.

Whatever features, applications, special functions, number of modification keys you can fit is up to you. It can be simple, graphing, financial and/or complex.

The example that I attached is a relatively simple scientific calculator design that would be either a solar-powered calculator or an app. Features include linear regression, algebraic and RPN entry modes, and basic scientific functions.


http://edspi31415.blogspot.com/2014/05/s...lenge.html

[Steve Simpkin]

But Eddie, where's the Enter key. How can anybody use a calculator without an Enter key

[Thomas Klemm]

(05-05-2014 12:46 AM)Steve Simpkin Wrote:  How can anybody use a calculator without an Enter key

cf. Sinclair Scientific

[Steve Simpkin]

(05-05-2014 04:41 AM)Thomas Klemm Wrote:  

(05-05-2014 12:46 AM)Steve Simpkin Wrote:  How can anybody use a calculator without an Enter key

cf. Sinclair Scientific

LOL
Point taken, although calling the Sinclair Scientific a "Calculator" is being generous
(with all due respect to Nigel Searle's ingenuity).
I built a Sinclair Wrist Calculator around 1977 and I have vivid memories of the experience...

[walter b]

(05-05-2014 04:41 AM)Thomas Klemm Wrote:  

(05-05-2014 12:46 AM)Steve Simpkin Wrote:  How can anybody use a calculator without an Enter key?

cf. Sinclair Scientific

@Thomas: Nice link but terrible calculator - could only be justified by replacing a slide rule. Or quoting Albert: Everything should be made as simple as possible - but not simpler. The Sinclair Scientific definitly crossed that limit IMHO.

@Steve: I concur.

@Eddie: Come on, you can do better!

d:-I

[Thomas Klemm]

(05-05-2014 08:21 PM)walter b Wrote:  @Eddie: Come on, you can do better!

You can't complain: he didn't use LOG for the common logarithm.

[Les Bell]

(05-05-2014 04:41 AM)Thomas Klemm Wrote:  

(05-05-2014 12:46 AM)Steve Simpkin Wrote:  How can anybody use a calculator without an Enter key

cf. Sinclair Scientific

I had one of those, built from a kit in 1974 (a bargain at GBP14.95!). Once the faulty clock chip was replaced (apparently TI supplied a bad batch), it worked almost adequately. But the killer wasn't the lack of an Enter key - it was the lack of a 1/x or x<>y key which, when coupled with a 3-level stack, meant that one had to resort to writing down intermediate results.

Still, it's not all bad news - it drove me to buy an HP-45, for which I shall be eternally grateful.

[Manolo Sobrino]

(05-05-2014 10:11 PM)Thomas Klemm Wrote:  You can't complain: he didn't use LOG for the common logarithm.

[Les Bell]

(05-04-2014 10:30 PM)Eddie W. Shore Wrote:  You have only 25 keys to work with. That's it.

Hey, Eddie! I fixed your keyboard layout for you. Now it's something we can work with.

[Eddie W. Shore]

(05-06-2014 03:02 AM)Les Bell Wrote:  

(05-04-2014 10:30 PM)Eddie W. Shore Wrote:  You have only 25 keys to work with. That's it.

Hey, Eddie! I fixed your keyboard layout for you. Now it's something we can work with.

The double-wide ENTER key.

[Eddie W. Shore]

(05-05-2014 12:46 AM)Steve Simpkin Wrote:  But Eddie, where's the Enter key. How can anybody use a calculator without an Enter key

I was intending the equals key to act as the ENTER key in RPN mode.

[Dale Reed]

My contribution follows.

Because I got an HP-25 (instead of a car) for my 18th birthday, and because it has 25 keys, I thought I'd name mine the DR-25S.

I tried to get all the scientific functions on it up through the HP-33C (sorry, guys -- no SOLVE or INTEG), plus add the binary, octal, hex and their bit operations (Bit-wise AND/OR/XOR/NOT etc. in "BIT" menu), plus some other stuff that I find most useful in MY work. (This is a calculator I would want. As I have done some microcontroller projects with custom PC boards and have a 3D printer, plus most of the parts, I might just make this one!!!)

   

My priorities:

• RPN (big Enter key a must)
• Basic Math (double-precision IEEE float required)
• Binary / Octal / Hex display and bitwise integer ops
• Programming with LBL, GTO, GSB and RET
• Trigs, Hyps, Logs, Exps
• Basic stats with linear regression
• Polar/Rectangular, Degree/Radian and H/H.ms conversions on keyboard
• Menus for long-list-ish stuff: constants, comparisons, parts, conversions
• USB, IR printing, Micro SD Card (with menus for each)
• 4-line 20-char LCD (easy interface, but room for menus or show 4-level stack)
  

I figured three shifts (like 34C, 65, 67) would work. I tried to do f and f(inverse) like 65, but it just wasn't to be. So it's f, g and h together on the left. (Yellow, blue, black is fine by me, like 67 / 34C)

I've tried to be smart about grouping:

Programming on the shifted left keys:
SST, BST, GSB, GTO, PSE, DEL, Flag menu, CMP (comparisons) menu.

Stack manipulation unshifted on the top row:
ENTER, Roll Down, X/Y exchange (I'm used to a 4-level stack, and no room for Roll Up)

Memory manipulation shifted on the stack manipulation keys:
STO, RCL, X/mem exchange, I and [I]

Number entry on the upper right:
EEX, +/-, LastX

Slide rule stuff on the top shifted:
SqRt, y**x, ln, e**x, log, 10**x (Yes, I use "log" for base 10. Sue me.)

trig, hyperbolics, D/R and R/P shifted on the 789 and 456 rows
sin, inv sin, cos, inv cos, tan, inv tan,
sinh, inv sinh, cosh, inv cosh, tanh, inv tanh
Polar / Rectangular conversion, Degrees / Radians conversion
(Hours / Hours.MinutesSeconds conversion right below those)

Binary, Octal, Hex, Decimal integer and bit ops shifted on the 123 row
("16#0000_01DE" is the style used in IEC-61131-3 PLC languages. Now you know. I like it, I'm used to it, I'm keeping it.)

Most menus h-shifted on the 123 row.

Stats on the shifts of the 0. row.
Avg, SampleSD, x-hat, y-hat, LR, r

All clears on the <--- key, including UNDO (except ClearSum)
Sum+, Sum-, ClearSum on the + key

Modulo, 1/x close to the divide key.

Most-used functions on the corners:
Plus (Sum+)
Run/Stop (Power on/off)
Enter (STO, SST)
CHS (log 10, 10**x, 1/x)

A, B, C, D, E, F double as Labels (in float, bin, octal, decimal) and as Hex entry keys [f] [16#] [0] [1] [h] [D] [h] [F] (h like in "hex") to enter 0x01DF, for example. Say it to yourself: "zero one hex-D hex-F" as you type it in... And just hit [f] [16#] [ENTER] to select hex display mode. Sweet...

So, Eddie, Walter, Pauli, and all ---- how'd I do?
Dale

[Steve Simpkin]

Dale,

Very intriguing design. I like it a lot. Somewhat between a 31S and a 34S.

I also bought my HP-25 instead of a car (on my 16th birthday). When I bought my first car 11 months later, it cost considerably less than half of what I paid for my HP-25. I thought both were a bargain

[bhtooefr]

Here's 24 keys, in a layout I mocked up for a 41-compatible watch idea I had:



So, the UI is somewhat menu-driven - SET (settings, including ASN, submenus for number format, trig representation, and the clock), TRG (ASIN, ACOS, ATAN, P→R, R→P), MTH (x^2, 10^x, LN, e^x, %), STT (Σ+, Σ-, CLΣ), PRG (LBL, GTO, ISG, RTN, BEEP), FLG (SF, CF, FS?), and CMP (X=Y?, X≤Y?, X>Y?, X=0?, FS?) are menus.

Now, when I mocked that up, the idea I had was to have four extra buttons (total of 28) for On (which would not actually turn it on - it would act as a mode selector ala the mode selector on my Casio CA53W-1, switching between watch (CLOCK), calculator, and stopwatch (SW), with using any functionality at the calculator or stopwatch causing it to reset to watch on the next press), User, Prog, and Alpha. However, to get it down to 25 keys... it's doable to stuff USER in the SET menu, PROG in the PRG menu, and then make Alpha a Shift-On.

Alpha, by the way, is implemented through the rather annoying system of cell phone keypad entry, but hey, it's better than 42S entry.

I also had the idea of multiple display modes, so you could have a fully backwards compatible display like this:



Or multiple visible stack levels like this:



(the menu options at the bottom look like crap, I'll admit)

[Joe Horn]

(05-04-2014 10:30 PM)Eddie W. Shore Wrote:  Design the keyboard of a scientific calculator and post links to your designs as responses to this blog entry. Rules:

You have only 25 keys to work with. That's it.

Ok: How about having no permanent key map at all? Imagine this: clear keys which contain an LCD which can dynamically change what each key has "printed" on it. Instead of menus, the keys themselves would change as you press keys. I'm talking about raised, tactile-feedback keys; hardware keys which contain soft keys. (Not touch-screen stuff!)

If keyboards were dynamic like this, there would be no need to worry about the original key assignments, since the user could re-arrange everything in any way they like, with as many shift keys as they want, called whatever they want, wherever they want them. No cluttered keyboard; no wasted keys; hundreds of functions easily available in at most 2 keystrokes, and thousands in at most 3 keystrokes, all on a keyboard with only 25 keys.

The keys could be bigger too, since nothing needs to be printed on the land area around the keys, or on the front bezel of each key.

All of this was proposed in the PPC Journal over 30 years ago. I'm still hoping for it. It'll be expensive, but once you use it, static keyboards will feel like something from the stone age, and nobody will want to go back. <end of sales pitch>

[bhtooefr]

The Samsung Alias 2 wasn't particularly expensive... $320 off contract apparently, in 2009, and that's for a cell phone with an EVDO radio.

[Massimo Gnerucci]

15 OLED keys!

[walter b]

(05-08-2014 10:24 AM)Massimo Gnerucci Wrote:  15 OLED keys!

Hmmh, a nice concept ... of 2008. Apparently didn't go any further.

[bhtooefr]

That was actually a cut-down version of this monstrosity:

http://www.artlebedev.com/everything/optimus/maximus/

And this is the latest version:

http://www.artlebedev.com/everything/optimus/popularis/

[Paul Dale]

It looks like this is available: http://www.artlebedev.com/everything/optimus/popularis/

More keys than a calculator really needs, but it has what looks like a decent display built in. HP 71B upgrade anyone?


- Pauli