A very photogenic couple

[Dave Britten]

I tracked down a couple of these small Casios recently, and they're some of the most attractive calculators I've seen (fortunately they also have pretty good functionality too).

   

On the right is the fx-4000P. This is a scientific model, that is most easily described as "an fx-7000G without graphing, and with a little more memory". It's got standard 1st-gen Casio BASIC, with one superficial quirk: custom prompt messages are separated into two steps. So "TRIALS"?->T on most other models would be "TRIALS":?->T here. It supports array memories for easy indirect addressing, and actually has more RAM available than the fx-7000G: you get 550 bytes for programs or additional memories, as opposed to 422 on the grapher. Another interesting difference: the fx-4000P will handle 32-bit numbers in binary mode, whereas nearly all graphing models (including its closest relative, the fx-7000G) are limited to 16-bits. Overall, I'd say it compares well to something like a 32S. It's a little better in some respects, and not quite as good in others. It's made more impressive by the fact that it predates the 32S by roughly 3 years.

The left is an FC-200, the financial version of the duo. Unlike the more recent FC-200V, this one is fully programmable. Well, almost - it's lacking some of the Casio BASIC features found on the other 1st-gen graphers or the fx-4000P: no custom string prompts, no array memories, no >= or <= (the other comparisons are still present). But in exchange, all financial functions and variables are usable within programs. There's also not as much program memory on offer: just 262 bytes. I suspect some RAM had to be sacrificed to make room for the financial variables and cash flow data. The way they handled solving for n in TVM is pretty clever. It displays n rounded up to a whole number, like the 12C calculates, but the actual stored value keeps the fractional part. In terms of programming, it easily bests the 12C, as you can use labels and subroutines, insert steps, and see the program text rather than numeric key codes. It does not have built-in bond and depreciation calculations, however. Interestingly, dates are stored as a separate data type. You enter them by pressing [DATE] three times - once each after entering the month, day, and year - and you can perform simple arithmetic between dates, or between a date and an integer, and store dates into memories.

Both have lovely physical design. They're very slim, have good screen contrast, and are equipped with hardware power switches and contrast dials. The keyboard design is... interesting. It's not bad by any means, but it's almost the polar opposite of an HP. It's mushy, with about 2 mm travel, but very responsive and reliable. All in all, very nice machines if you're into 1980s symbolic/formula programmables.

[Csaba Tizedes]

Yes, the 4000P. My favourite CASIO (together with 50F). If you have any program, please post here. It is hard to find interesting things for these really powerful machines.

I store on my 4000P:

- "First Fit" bin packing algorithm (1D): at the start asks the capacity (in tons) of one container, then asks the packages weights. If the package fits inside one of the available container, push inside else opens a new container. (Good application of var[] addressing.)
- Sunrise-Noon-Sunset calculator: classic application, 207 steps, with output 221 steps. Accuracy +/- 1-2 mins typically (which is good enough for amateur astronomy).
- 1D Min/Max (local) search program without differentiation: Works like a ball in the ditch. Simple rolls down to the bottom.

If you have any program, please post it and if you interested, I am ready to post these programs also.


Thanks,
Csaba

[Dave Britten]

Here's my Tower of Hanoi solver that I adapted from an fx-7000G version I wrote. Instead of a graphical display, it uses this output format:

FT.XYZ

Where F is the stack to move from, T is the stack to move to, and X, Y, and Z indicate the total number of disks on the left, middle, and right stacks respectively.

This uses extensive register packing to store all three stacks in just three variables, as well as a small array to store pointers to the tops of each stack. (Note that there are some uses of variable O; be careful not to mistake this for zero.)

Code:

==Prog 0==
Fix 3
Mcl
"DISCS":?→N
2Frac (N÷2→O
2^N-1→M
9→P~R
N→U
9→V
18→W
U→I
Lbl 0
N-I+1→D
Prg 2
Dsz I
Goto 0
1→B
Prg 3
Lbl 1
B→F
B+1+O→G
G>3⇒G-3→G
B+2-O→B
B>3⇒B-3→B
T[F→I
Prg 1
D→C
T[G→I
Prg 1
C<D⇒Goto 2
D→C
F→S
G→F
S→G
Lbl 2
0→D
T[F→I
Prg 2
Dsz T[F]:Deg (no-op)
Isz T[G]
C→D
T[G→I
Prg 2
Prg 3
Dsz M
Goto 1
Norm

==Prog 1==
P[Int (I÷9→Z
9Frac (I÷9→E
10Frac (.1Int (Z÷(10^)E→D

==Prog 2==
D→H
Prg 1
Z-D(10^)E+H(10^)E→P[Int(I÷9)]

==Prog 3==
10F+G+.1U+.01(V-9)+.001(W-18◢

[BruceH]

(08-22-2018 01:57 PM)Dave Britten Wrote:  It's got standard 1st-gen Casio BASIC, with one superficial quirk: custom prompt messages are separated into two steps. So "TRIALS"?->T on most other models would be "TRIALS":?->T here.

I bought one of these when I was at school in the early '80s and this string display was the most annoying feature by far. On the 501P/601P models the print command would display and pause, requiring the user to press EXE (or whatever) to continue. But if the print command was followed by a semi-colon, the calc would continue without waiting for the user acknowledgment. This was very handy for displaying progress through a loop while still being able to display results to the user at the end so they could be written down.

The 4000P lost the semi-colon capability which was very annoying to me at the time. (Now I realise Casio were just preparing me for a lifetime of disappointment as tech companies take away features for no good reason!) ;-)

[Dave Britten]

(08-25-2018 04:41 PM)BruceH Wrote:  I bought one of these when I was at school in the early '80s and this string display was the most annoying feature by far. On the 501P/601P models the print command would display and pause, requiring the user to press EXE (or whatever) to continue. But if the print command was followed by a semi-colon, the calc would continue without waiting for the user acknowledgment. This was very handy for displaying progress through a loop while still being able to display results to the user at the end so they could be written down.

The 4000P lost the semi-colon capability which was very annoying to me at the time. (Now I realise Casio were just preparing me for a lifetime of disappointment as tech companies take away features for no good reason!) ;-)

That's always been one of my pet peeves about Casio. On the old models, there's no way to display a numeric result without pausing the program. You can display strings all you want by putting a string literal all by itself on a line, but for displaying numbers, you have to use that blasted little triangle that pauses execution. At least the newer models let you use Locate to write text and numbers on the screen without stopping, but you have to write to specific coordinates, i.e. it's not like a stream of "PRINT" in BASIC.

[rickh57]

I had a fx-4000p in college in the 80s. It helped me through a probability and statistics class. When I showed to to a friend, he was amazed to see more than just digits showing on a calculator screen. [I'm actually on the hunt for one on eBay to add to my calculator collection. I wish that I had kept my original one.]

[Hollerith]

To Dave Britten

You can get scrolled output on Casio Graphical Calculators by the following method.

First ensure the output "cursor" is on line 7"

For 1->I To 7
" "
Next

N.B. " " contains a single space character. A space character is required for CFX-9850G (and others?), but later calculators (e.g. FX-9860G and CG50) it can be a zero length string.

Then all you have to do is output a zero length string ("") followed by a Locate on line 7. The screen will scroll up and the Locate will add new output on line 7.

For example to output numbers 1 to 20 with scrolling

For 1->I To 20
""
Locate 1,7,I
Next

Hope this is useful.