Using the Interface
The applet interface is divided into two major parts: the machine display and
the programming controls. The display includes the tape itself (with the
current cell hilited in the center), arrows for scrolling it manually, and some
controls used in running the program. "Start" resets the machine and runs it,
"Stop" causes it to halt, "Resume" restarts the machine without resetting
anything, and "Step" is used to execute a single transition. The "Speed" option
may be set to "slow", "fast", "very fast", or "compute"--the last runs as
quickly as possible and without displaying any of its operations on the tape,
which is helpful mainly for testing Busy Beaver
machines that may execute millions of transitions before halting. Upon halting
the message box (in the lower right-hand corner of the applet) displays the
reason for the halt, the total number of transitions in the run and the total
number of non-blanks now on the tape, the last two of which are again mainly
useful for Busy Beaver programs.
In the middle of the applet is a pull-down list with some preset Turing
Machine programs that you can load and run. This is the easy way to do things;
the programs are automatically installed upon loading. Choose the "<New>"
option to reset all fields and to clear the programming box (see below).
Following this are some basic specs for the current machine: name
(optional), initial position, and initial characters (optional--the tape may be
blank to begin with), all of which may be set (initial position and initial
chars can be changed without having to reprogram).
On the lower left is a text box for displaying and/or entering the transition
table code for the current machine (see How to
Program). This code is not actually set up to run until you press the
"install program" button on the right. The other box on the right is just a
catch-all message area to reflect what's going on in the rest of the applet.
Prev: What is a Turing Machine?
Next: How to Program
Back to the applet
Nature Photography |
Scrabble Challenge |
Worlds Apart |
Site Updated: 2023/Oct/6
Copyright © 2023, All Rights Reserved. Check the
credits before you borrow any of the graphics on these pages.