Electrical Engineering ⇒ Topic : Digital Computer

DIGITAL COMPUTER

The digital computer is an electronic machine having built-in intelligence to execute instructions.The main components of a digital computer are central processing unit (CPU), memory, input device and output device. Figure (a) shows the schematic diagram of a digital computer. A

                              Figure (a) Schematic diagram of a digital computer.

microcomputer is a small digital computer and its CPU is a microprocessor. Its other components are same as those of any other digital computer. Figure 32.2 shows the schematic diagram of a microcomputer. The physical devices of a microcomputer include electronic, magnetic,mechanical devices, etc. The physical devices together with the circuitry of a computer is known

                                    Figure (b) Schematic diagrann of a microconnputer.

as hardware. A program is a sequence of instructions to perform a particular task, which are called software. Peripherals are nothing but the input and output devices.

Memory stores the program, data and results before and after the execution of the program.There are two classes of memory, i.e., RAM and ROM. Computer can read the information from the Read Only Memory (ROM) as and when required. Random Access Memroy (RAM) is also known as read and write memory. Computer can read the data in this memory as and when required. Moreover, it is possible to alter the contents of this memory