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!!!)

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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