It is simply a computer that enables the user to write, modify, debug & test programs. In a microprocessor-based development system, a microcomputer is used to develop software for a particular microprocessor. Generally, the microcomputer has a large R/W memory(typically, 8M to 64M),disk storage, and a video terminal with an ASCII keyboard.
The system (I/Os, files, programs,etc.) is managed by a program called the operating system. The hardware & software features of a software development system are described in the next sections.
Software development system includes an ASCII keyboard, a CRT terminal, an MPU board with 8M to 64M R/W memory and disc controllers, and disk drives. The disk controller is an interfacing circuit through which the mpu can access a disk & provide Read/Write control signals. The disk drives have Read/Write elements, which are responsible for reading and writing data on the disk.
At present, most systems are equipped a 3.5- inch disk stores 1.44M bytes of information. The storage capacity of a typical hard disk in a pc is 2.2G(giga) bytes or higher.
It is made up of a thin magnetic material (iron oxide) that can store logic 0s and 1s in the form of magnetic direction. The surface on the disk is divided into a number of concentric tracks, & each track is divided into sectors. Data are stored on concentric circular tracks on both sides(known as doubled-sided). At the edge of the disk there is a ‘notch’ called write protected notch.
Another type of storage memory used with computers called a hard disk. In general the disk is fastened in a dustfree drive mechanism. It is highly precise & reliable. It requires sophisticated controller circuitry. It is more stable than the floppy disk. They are available in various sizes & their storage capacity is quite large in the order of gigabytes.
A cd-rom is a optical disk that uses a laser beam to store digital information that can be read with a laser diode. The disk is immune to dust and mechanical wear because of its optical nature. It comes in various size(3.5-14inch) and stores huge amount of data from 100mb to several gb.
The operating system of a computer is a group of programs that manages or oversees all the operations of the computer The computer transfers information constantly among peripherals such as a floppy disk, printer, keyboard and video monitor. Its also stores user programs under file name on a disk
Each computer has its own operating system. Known as MS-DOS(Microsoft Disk Operating System), OS/2(Operating system 2), Windows95(98) and UNIX. MS-Dos is being replaced by newer operating system such as Microsoft Windows 95 (windows 98), IBM, OS/2 (Operating System 2) and UNIX.
It is designed to handle 16-bit data word and 640k memory system and disks with quad(high)- density disk format with memory capacity of 720K and 1,200K. Similarly, it can support a hard disk and includes a hierarchial file directory. It supports: Multitasking Telecommunications multimedia
It is a multitasking operating system, meaning the user can run multiple applications concurrently. WINDOWS 95(98): it is a 32-bit single user o/s designed by Microsoft. It has graphical interface and it supports the use of mouse, icons and menus. It is also a multitasking o/s similar to O/S2 WINDOWS 98 is an upgraded version of windows 95.
It is a multiuser, multitasking o/s. It was designed for mini computers but it is now used on various machines ranging from Microcomputers to Supercomputers. It is widely used in: Engineering Scientific Research Environment
It is well suited for Networking and Graphical environment. Eg:- Solaris (it is widely used in high end microcomputers such as workstation and network servers) (It was designed by Sun microsystem) (It is capable of handling 64 computers and is being upgraded to 128 computers)