Patent ID: 8480398
Filing Date: 2013-07-09
Classification: G09B

Abstract:
1. A method for teaching the workings of an Operating System multiprocessing mechanism, the method comprising steps “a” through “l” of the following stepwise process of constructing and operating and educational model computer system, the steps including: (a) Building an instruction-execution driver logic-circuit that implements: (b) Building logic circuits that implements the application program instructions “increment register A”, “increment register B”, “Jump_ProgA” that jumps to the start of program A at RAM location 0010, and “Jump_ProgB” that jumps to the start of program B at RAM location 1001; (c) Reserving locations 0000-0011 of a 16×4 bit RAM for Operating System multiprocessing instructions, reserving RAM locations 0010-1000 for application program instructions of a process A, and reserving RAM locations 1001-1100 for application program instructions of a process B; (d) Configuring a buffer chip named ProgA_ptr with the value 0010, and connecting the output pins of this chip to a data transfer BUS; (e) Configuring a buffer chip named ProgB_ptr with the value 1001, and connecting the output pins of this chip to the data transfer BUS; (f) Building a hardware process-queue consisting of three 4-bit registers R (g) Building logic circuits for the following Operating System instructions that operate on the process queue of the above step “f”: (h) Building a process interrupt circuit that counts the number of instructions that a running process executes and generates a preemption interrupt signal after the tenth instruction wherein this signal preempts the running process by moving a PC value into R Initialize, Wakeup_process, Update_process_queue, Wakeup_process; (i) Programming the RAM locations for program A reserved in step “c” above with application program instructions of step “b” above, preferably with an instruction IncA, the last instruction being “Jump_ProgA”; (k) Programming the RAM locations for program B reserved in step “c” above with application program instructions of step “b” above, preferably with an instruction IncB, the last instruction being “Jump_ProgB”; and (l) Running the computer with initial PC value of 0000 and observing the cyclic alternating execution of program A and program B, whereby running a program is preempted by Operating System hardware after running ten instructions, and the execution of the other waiting program is started by the Operating System software.