Structure of Computer Systems Operations

Structure of Computer Systems OperationsThere is no specific provisions on how to structure a computer system. Every expert and designer computer architecture has a view of each. However, to facilitate us to understand the details of the operating system in the following chapters, we need to have a general knowledge of computer system structure.In general, computer systems consisting of CPU and a device controller that is connected via a bus that provides access to memory. Generally, each device controller is responsible for a hardware spesisfik. Each device and the CPU can operate concurrently to gain access to memory. The existence of multiple hardware can cause synchronization problems. Therefore, to prevent a memory controller is added to the synchronization of memory access.At a more advanced computer system, its architecture is more complex. To improve performance, use multiple buses. Each bus is a data path between several different devices. In this way the RAM, processor, GPU (AGP VGA) connected by high speed primary bus is better known as the FSB (Front Side Bus). While other devices connected by a slower bus speed is lower that the other is connected with a faster bus to the main bus. For communication between the bus is used by a bridge.Responsibility for bus synchronization indirectly also affect memory synchronization is done by a bus controller or bus master is known as. The bus master will control the flow of data up to at one time, the bus only contains data from a single device.In practice the bridge and the bus master is bound together in a chipset.

NB: GPU = Graphics Processing Unit; AGP = Accelerated Graphics Port; HDD = Hard Disk Drive; FDD = Floppy Disk Drive; FSB = Front Side Bus: USB = Universal Serial Bus: PCI = Peripheral Component Interconnect; RTC = Real Time Clock; PATA = Parallel Advanced Technology Attachment: SATA = Serial Advanced Technology Attachment; ISA = Industry Standard Architecture; IDE = Intelligent Drive Electronics / Integrated Drive Electronics; MCA = Micro Channel Architecture; PS / 2 = A port that was built to connect the mouse to the IBM PC ;
 If the computer is turned on, which is known as booting, the computer will run the bootstrap program is a simple program which is stored in a ROM chip in the form of CMOS (Complementary Metal Oxide Semiconductor). Modern CMOS chips usually type EEPROM (Electrically Erasable Programmable Read Only Memory), a non-volatile memory (not lost if the power is turned off) which can be written and erased with an electronic pulse. Then bootsrap this program better known as the BIOS (Basic Input Output System).Bootstrap main program, which is usually located on the motherboard will examine the major hardware and hardware-initialization of the hardware program known as firmware.Bootstrap main program will then find and load the operating system kernel into memory and then proceed with the initialization of the system here operasi.Dari operating system program will wait for certain events. This event will determine what to do next operating system (event-driven).This event on modern computers are usually marked by the emergence of software or hardware interrupt, so the operating system is called Interrupt-driven. Interrupt of hardware is usually delivered via a specific signal, while the software sends an interrupt by invoking a system call or also known as the monitor call. System / Monitor This call will cause a special interrupt trap is generated by the software due to problems or requests for operating system services. Trap is also often referred to as an exception.Each interrupt occurs, a set of code known as the ISR (Interrupt Service Routine) will determine the action to be taken. To determine what actions to take, it can be done in two ways: polling that makes the computer to check one by one device that is to investigate the source of the interrupt and how to use the ISR addresses stored in the array is known as the interrupt vector in which the system will check Interrupt Vector each time an interrupt occurs.Interrupt architecture must be able to store the address of the interrupt instruction. On older computers, this address is stored in a particular place remain, while new padakomputer, the address is stored in the stack, together with state information at the time.