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Some time back in high school (Gymnasium Thun Schadau), when we had one of our first math lessons, we got our hands on a programmable calculator - the Voyage 200.

For just about 150 CHF, a whopping 12 MHz CPU and 256 kB RAM were at our free disposal - the possibilities were endless.

Man, we just loved our new calculator. Coding, writing stupid simple programs all day long, scrolling by hand through pages and pages of code by hand.

That thing even could render 3D functions on a 240 × 128 pixel screen! Most of the fun we had with the built-in language TI Basic, which provided a fairly easy way to write our own programs and also exchange them via a link cable. There was also quite some community with software, games and all kind of tools at ticalc.org, most of it still available.

Most of the time we were programming during class, especially math, as it was unsuspicious to be working on the calculator during math :-) Another great usage was as a "help" in physics, with formulae, custom notes, solutions, which of course were also shared amongst us.

Some comment / author sections of shared programs:

When going through all the programs on the calculator I found some fun stuff and tried to have a look at it and get it on a modern computer. So I installed TI Connect, fired up the old calculator and had a look at some programs we wrote.

For example a simple program for finding pythagorean triples looked like this (some calculator-specific symbols are already replaced):

START92
COMMENT=saved with TI++ v.2.03.0001
NAME=triple
FILE=TRIPLE.89P

Prgm
For x1,1,100
  For x2,x1,100
    If mod(root(x1^2+x2^2),1)=0 Then 
      For x,1,z
        If mod(x1,d1[x])=0 and mod(x2,d2[x])=0 Then 
          Goto weiter
        EndIf
      EndFor
      z+1->z
      x1->d1[z]
      x2->d2[z]
      {x1,x2,root(x1^2+x2^2)}->l
      Disp l
    EndIf
  Lbl weiter
  EndFor
EndFor
EndPrgm
STOP92

You can download some exported programs here. Note: Use at your own risk. Some programs weren't even working back then :-)

Here some screenshots from some of the programs:

School in general

• Keeping track of marks & exams

• Calculation of minimal mark to get a passing grade

• A searchable formulary, you could enter a physical variable to search for and get a definition and matching formulae.

Math & co.

• Trigonometry: Enter three parameters and get the the missing sides and angles.

• Spherical trigonometry: Similar to the app above, but with more complex formulae to calculate the missing angles.

• Finding pythogrean triples

• Calculation of interests

• Recognizing the base function from a series of numbers

• Deriving expressions

• Burning stuff in chemistry (energy calculation?)

• Physics: Simulation of a falling object

Data visualization

• ASCII images

• Simulation of the Doppler effect (or something alike)

• A basic Excel-like drawing program

• Screen savers: I was really obsessed with screen savers, even if they totally failed the point on that kind of screen.

• A simple drawing program

• Monitoring radioactive decay

• A fake loading bar with random progress :-)

• Visualization of random number generation

• Some experimentation with fractals

• Sine/cosine with text

Games

• Connect 4: We even wrote a Multiplayer "Connect 4" game, where we would connect our calculators to play connect 4.

• A simple (unfinished) Poker prototype

• A Multiplayer TicTacToe - this one really worked and could be played over the link cable!

We also spent tons of time playing Phoenix, an assembly game:

See also Assembly Games. You can play Phoenix clone I made a while ago in your browser, see this blogpost.

Thanks for reading!