When you can see inside a computer...
We have found it an excellent tool for the delivery of the machine architecture aspects of A level Computing. IT facilitates well demonstrations by the teacher but most importantly enables hands-on work by the students. It offers a safe and reliable working environment for the students, the interface is intuitive and useable, and certainly we have found that students gain a greater understanding of the topic through using TOM than would be the case with more traditional methods of delivery Paul Morgan, Sir John Deanes College.
This is real education, deep stuff. Its informative, accurate, interesting and recommended. I dont want to give it back." Parents & Computing
Students following a first course in computing often experience difficulty in understanding the fundamentals of computer operation. A sound basis cannot be developed without a working knowledge of the capabilities and limitations of a stored program computer. Unfortunately it is not possible for inexperienced students to study computing with any degree of success as there is no computer that is both realistic and easy to use. TOM has been developed in order that such initial instruction can be given, involving suitable practical experience to allow students to develop their confidence and competence before their initial enthusiasm is exhausted.
TOM stands for Thoroughly Obedient Moron, and consists of a number of components each designed to teach the fundamentals of computing via simple interactions. The above screen shows TOM's machine which gives a full simulation of how each TOM instruction is executed.
The student can interact with the above screen to gain a deep understanding of precisely how a computer achieves its task.
This simple computer has a safe and friendly interface which is entirely mouse driven.
TOM has 20 instructions, a manageably small number which nevertheless enables real programs to be written. The entire status of TOM is visible at all times giving instant feedback on the state of the execution. Programs may be executed, single stepped, saved, restored, and modified.
The main TOM screen, shown above, behaves exactly as with version 1 but additional options allow programming of memory mapped output and interrupts for the more advanced aspects of current computing courses. In addition, Stack Pointer and Status registers can be enabled to allow a greater range of programs to be written.
The above screen shot shows the optional keyboard device which can provoke processor interrupts for which the students can provide interrupt handlers. Also shown is the memory mapped output device which maps the ASCII collating sequence to displayable characters.
These additional components give students a firm grasp of how input/output operations and subroutine calls are performed by modern computers.
All programs written for TOM can be executed by TOM's machine, as shown on the previous page, where each aspect of execution can be seen in detail.
TOM has been enhanced to allow copying, cutting and pasting of memory contents to facilitate program correction and can display memory contents in decimal, hexadecimal and binary. The following video shows the basic operation of TOM by programming a simple loop and gives an example of a more complex program.
The following video shows the operation of TOM's underlying machine which shows how individual instructions are executed and gives a very deep understanding of how a computer works.
Logic gates are the fundamental building bricks of digital computers. No student can completely understand the modern digital computer without a firm grasp of what logic gates do and how they can be connected to achieve complex logic circuits.
Interactive screens take the user through:
Each interactive display shows an active truth table and explanation text wherever relevant and is backed up by Help File and tutorial style documentation.
The above screen shows the flip-flop display which gives a blow by blow display of Set and Reset sequences.
TOM builds upon this layer of abstraction to show how via the Controlled Flip-Flop a set of memory elements can be built and addressed.
A succession of screens takes the user interactively through how the components of memory are constructed, from a simple array of controlled flip-flops, address decoding, finally to the above screen which interactively demonstrates how values are fetched from particular memory addresses.
There is a substantial context sensitive Windows Help file and User Manual. The manual gives background information on all aspects of TOM and includes discussions of:
The TOM manual includes exercises on each topic and can be successfully used in a self-teaching mode leaving the instructor free to supervise. TOM has been used most successfully for at least five years during a Fundamentals of Computer Science course and is now widely used in British schools. It is suitable for all students who are starting their studies of computers.
Review of TOM Simulator from Parents & Computing
Ordering TOM Simulator using order form