Operating System Memory Page Sharing
In a paged environment sharing of memory among processes provides numerous benefits including sharing non-self-modifying reentrant code and interprocess communication. More ...
Logical Versus Physical Memory Addresses
Computers use logical and physical addresses to access memory locatiuons. The CPU generates logical addresses. At run-time the Memory Management Unit (MMU) maps logical addresses to physical addresses. More ...
Microcontroller Internal EEPROM (Electrically Erasable Programmable Read Only Memory) Memory
In some situations it is required that some program parameters such as configuration settings be keept after the system is powered off. This is made possible by including a EEPROM internally to the microcontroller. More ...
The Motherboard Chipset
Because the chipset dictates the bus speed, type and amount of memory, and the type and number of I/O ports, much of a computer's performance is determined by its chipset. More ...
Capacitors in DC Circuits
A capacitor is a component that can be used to store an electrical charge. A capacitor can be used to create a timer. This time delay can be used to smooth a changing current flow in a circuit, or it can be used to absorb spikes and prevent false triggering of other components. More ...
How Computer Chips are Made
The oxygen is removed from silica by heating it with carbon. A tiny seed of silicon is then dipped into molten silicon. As the tiny crystal is slowly lifted out of the crucible silicon crystallizes around it. More ...
ARM Cortex-A72 Registers
16 registers r0 - r15 are accessable in the ARM Cortex-A72 user mode. In addition part of the CPSR (Current Program Status Register) is accessable. That part is the APSR (Application Program Status Register) which contains conditional status bits. More ...
Multilevel Queue CPU Scheduling Algorithm
With many CPU scheduling algorithms, all processes are placed in a single queue, and the scheduler selects the process to run. In practice, it is often easier to have separate queues for each priority, and the scheduler simply selects the process in the highest-priority queue. More ...
Computer Video Display
If you view a computer as an input-processing-output machine, you can use a keyboard or removable storage device as the input, a program as the processing, but what can you use to retrieve the output? One way to acquire the output, be it text or graphics, is with a video display. More ...
Operating System Process Scheduling Queues
The objective of multiprogramming is to have some process running at all times, to maximize CPU utilization. To meet these objectives, the process scheduler selects a process from a queue for execution on the CPU. More ...
Operating System Processes
An Operating System Process is a program in execution. It includes the value in the program counter and in the processors registers. A process also includes a stack, data section, and a heap. More ...
Operating System Memory Protection in a Paged Environment
Memory protection in a paged environment is accomplished by protection bits associated with each frame. For example read-write, read-only or execute-only bit, and valid-invalid bit. Normally, these bits are kept in the page table. More ...
