Matt McCutchen's Web SiteLogic Designer  (Top, Quick tutorial, Version log, Bottom).  Email me about this page.

The Logic Designer splash screen A clocked JK flip-flop in action

Logic Designer

Status: unmaintained; 2005-2007 (supersedes any conflicting remarks left on this page; see the home page for definitions)

Here you will find the Logic Designer, a program for AMS calculators (TI-89, TI-92 Plus, Voyage 200) that lets you build and run circuits of logic gates.  It supports the gates (N)AND, (N)OR, XOR, EQUIV, NOT, 0, 1, junction, switch, and light.  It has a nice graphical editor and simulator where you can flip switches and watch what happens.  The program was written on a TI-89 but is also known to work on the TI-92 Plus, and it should work on any recent AMS calculator because it automatically detects the size of the graph screen.  Circuits can be loaded and saved as DATA variables, which are compatible between AMS calculators.  The program includes three screens of online help.

The Logic Designer consists of about 100 variables that are normally installed into the folder logicdes.  It tries very hard to be well-behaved with respect to folders.  The main program, logicdes\logicdes, can be invoked with any current folder; the Logic Designer changes into the install folder (so it can find the rest of itself) and restores the original folder when it quits.  The Logic Designer keeps runtime variables in the install folder alongside the variables constituting the program; it is recommended to keep the latter variables locked or archived so they can be distinguished from the others.  You can run cleanup in the install folder to remove all runtime variables.  On the other hand, the Logic Designer loads and saves circuit files in your original folder by default; you should not keep your circuit files in the install folder because you might interfere with the program's operation.  Since version 2.0.3, the shell code has been moved to ldmain, and logicdes is a lightweight launcher that you can rename, move, and/or copy at your convenience; you might want to install it at main\kbdprgmX.  If you install the Logic Designer in a folder other than logicdes, just modify the launcher.  Since 2.0.2, a version list is included with the Logic Designer to remind you of the version you have.

Below there is a TI-89 group containing the Logic Designer; I hope this group will also install onto TI-92 Plus and Voyage 200 calculators.  Note that the programs may install into archive while in text format, in which case there will be repeated tokenizing delays as you use the Logic Designer (discussion); to avoid these delays, unarchive all the programs, use the Logic Designer for a while, and rearchive them.

A group of eight sample/demo circuits is also available.  So is a zip package containing a README and the Logic Designer and sample circuits in both grouped and ungrouped form; this package is posted here on

If you click on a group below and your browser navigates to a page of random characters, go back and use your browser's command to save the file to disk.

DescriptionFileSizeModification time
Logic Designer 2.1.1 grouplogicdes- 02:41:05 +0000
LD 2.1.1 zip packagelogicdes-2.1.1.zip508332007-04-18 02:53:18 +0000
Demo circuits grouplogicdes-demo-circuits-2.89g36582006-02-15 02:20:29 +0000
Logic Designer 2.1 grouplogicdes-2.1.89g241052006-04-02 21:04:14 +0000
LD 2.1 zip packagelogicdes-2.1.zip516932006-04-03 21:43:13 +0000

Quick tutorial[# Top]

Assuming you successfully installed both the program and the example circuits:

  1. Run logicdes\logicdes
  2. Press F2 to load, and type in: lddemo\adder
  3. Press F4 to run.
  4. Use the arrows and 2nd as necessary to move the cursor to the switches at the left.  Press 0 or 1 to flip the switches and watch the lights at the right update.  Press F4 for help on the other available simulation commands.
  5. Press Esc to return to the main menu.
  6. Press F3 to edit.
  7. Move the cursor to the bottom and press ) to create (and select) a light.
  8. Move the cursor to one of the switches at left and press F1 to wire the light to that switch.  Press F8 for help on the other available editing commands; also see the toolbar.
  9. Press Esc to return to the main menu and Esc again to exit.

(Added because someone asked, 2015-09-15.)

Version log[# Top]

Matt McCutchen's Web SiteLogic Designer  (Top, Quick tutorial, Version log, Bottom).  Email me about this page.
Modification time of this page's main source file: 2015-09-15 17:59:38 +0000
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