DM42 Appreciation Thread

CuteHat

[font=Arial]A thread all about the DM42 calculator by SwissMIcros.[/font]

[font=Arial]For any new people: the DM42 is like a modern rebuild of the HP-42S, a keystroke-programmable handheld calculator introduced in 1988. The DM42 runs on Free42, a GPL-licensed simulator of the HP-42S. The DM42 is incredibly precise out to 34 decimal places, is USB capable allowing the use of custom firmware, and uses RPN (reverse Polish notation) which is a vast improvement over typical mathematical inputs. RPN was developed in 1920 specifically for performing calculations with machines, and is faster, requiring fewer keystrokes.[/font]

[font=Arial]Free42 is opensource, and the DM42 encoder/decoder is available for making and converting human-readable files. There's a decent hacking scene for the firmware as well. I hope you all appreciate the DM42! Discussions of other calculators are welcome too (just not Texas Instruments >w>). Anyway, here's 2b:[/font]

[font=Arial]https://1.bp.blogspot.com/-g15XBIfZYJM/Wowf_i8R7iI/AAAAAAAAAE4/34gHY8O4NSwQHYcLvIOZaOmTdIoBJ-NXQCEwYBhgL/s1600/dm42-offimg-2b-1.jpg[/img][/font]

malmon

It looks really cool, but the price made my heart sink

Backlash

I got a TI nSpire CAS for freshman year, right? Worst purchase of my college career. That thing has like a mini trackpad in the middle of the directional bezel, which makes it awkward as hell to use, and none of my classes would even allow me to use it anyways.

Actually, come to think of it, I haven't touched that thing since graduating either. Hah, and they said I'd need to learn math to be a programmer.

On another note, is that an IBM Model M keyboard? ^^

malmon

Backlash wrote:
I got a TI nSpire CAS for freshman year, right? Worst purchase of my college career. That thing has like a mini trackpad in the middle of the directional bezel, which makes it awkward as hell to use, and none of my classes would even allow me to use it anyways.

Actually, come to think of it, I haven't touched that thing since graduating either. Hah, and they said I'd need to learn math to be a programmer.

On another note, is that an IBM Model M keyboard? ^^

Heh, I have the nspire CX. A pretty horrid calculator, but it can run Linux

malmon

This has actually gotten me quite interested in RPN. So far I've managed to program Free42 to solve quadratic equations. It took me three tries though >_>

[spoiler]

00 { 103-Byte Prgm }
01 LBL "QSLV"
02 INPUT "A"
03 CLST
04 INPUT "B"
05 CLST
06 INPUT "C"
07 RCL "B"
08 X↑2
09 4
10 RCL "A"
11 ×
12 RCL "C"
13 ×
14 -
15 SQRT
16 STO "SQDET"
17 0
18 RCL "B"
19 -
20 RCL "SQDET"
21 +
22 2
23 ENTER
24 RCL "A"
25 ×
26 ÷
27 STO "X1"
28 0
29 RCL "B"
30 -
31 RCL "SQDET"
32 -
33 2
34 RCL "A"
35 ×
36 ÷
37 STO "X2"
38 CLST
39 VIEW "X1"
40 STOP
41 VIEW "X2"
42 .END.

[/spoiler]

A lot of areas for improvement now that I can see more than two lines at a time

malmon

Also somewhat interesting that Free42 can't calculate Euler's identity. Though I guess that makes sense, given all the calculations are numerical

[spoiler]

00 { 18-Byte Prgm }
01 LBL "EULER"
02 0
03 PI
04 COMPLEX
05 E↑X
06 1
07 +
08 .END.

T=                     0
Z=                     0
Y=                     0
X= 0 -i1.15802830601ᴇ-34

[/spoiler]

CuteHat

malmon wrote:
This has actually gotten me quite interested in RPN. So far I've managed to program Free42 to solve quadratic equations. It took me three tries though >_>

Ah I wish I could give you input there--I'm interested in it but it quickly gets to be beyond the scope of my daily needs. All the math I do on a job is like, forest inventories and multivariable regressions. I do have to do a lot of math of devices day-to-day so as a fast input method for simple calculations, I like RPN. Very cool what you've done in Free42 though ^^.