The figure above shows the “Computer System Model” that a student builds via the “Computer System Kit”. For the amount of knowledge it delivers, this generic model stands out with its compact simplicity: A 16x4 bit RAM housing an OS, two application programs, and an interrupt routine, whereas a small CPU gives life to time-shared execution of the application programs under the management of the OS while implementing process synchronization and input interrupt processing. Please keep in mind that every instruction and function displayed in the figure above are built by the student via bread-boarding SSI (Small Scale Integration) circuit chips such as logic gates, flip-flops, counters, decoders, buffers, etc., and the programs are manually entered by the student.

You start with constructing the Basic Computer Model (see the sidebar menu) which implements the application program instructions (e.g., Increment RegA, Increment RegB). (Construction time: 16 to 19 hours).*

The Operating System module that you implement is designed for time-shared alternating execution of the application programs A and B. This module includes building of the Process Preemption Interrupt, the Process Queue, and the OS instructions listed in the figure above. (Construction time: 6 to 8 hours).

With the Synchronization module you implement the wait and signal operations which can be used in application-program A or B and demonstrate process synchronization. (Construction time: 3 to 4 hours).

The Input Interrupt Processing module implements and demonstrates handling of input interrupts. (Construction time: 3 to 4 hours).

Please note that the Operating System, Synchronization, and Input Interrupt Processing functions are designed as extension modules and you can choose to implement one or more of them.

* The construction times given above are generous approximations in view of the following assumptions:
a) The student has bread-boarding experience (e.g., acquired via the exercises in the lab project manual, ~ 2- 3 hrs).
b) The student has read the lab manual and has a good understanding of the particular project he/she is working on.
c) The student works carefully at a slow to moderate pace while avoiding overly time consuming errors.