Unit 1 PRIMARY STORAGE DEVICES LECTURE – 7 Primary storage:- Every computer has a temporary storage area which built into the computer H/W and in which instructions and data of a program reside mainly when the program is being executed by the CPU. This storage space is known as primary storage main memory or simply memory. Basic of Computer & 'C' programming
Unit 1 PRIMARY STORAGE DEVICES LECTURE – 7 RAM:- Random Access Memory:- usually RAM is a volatile. Computer main memory is built of volatile RAM chip. Basic of Computer & 'C' programming
Unit 1 PRIMARY STORAGE DEVICES LECTURE – 7 ROM:- Read only Memory:- ROM is non-volatile memory chip in which data are stored permanently and cannot be altered by the programmer. The data stored in a ROM chip can only be read and used. They cannot be changed. This is the reason why it is called read only memory (ROM). Basic of Computer & 'C' programming
Unit 1 PRIMARY STORAGE DEVICES LECTURE – 7 PROM:- A user Programmed ROM is one in which the user can load and store “read only” programs and data that is it is possible for a user to “customize” a system by converting his/her our programs to micro programs and storing them in user programmed ROM chip such a PROM is commonly known as programmable Read-only memory (PROM) because a user can program it. Basic of Computer & 'C' programming
Unit 1 PRIMARY STORAGE DEVICES LECTURE – 7 E PROM:- Erasable programmable Read-only memory (EPROM) erase information stored in an EPROM chip and the chip can be reprogrammed to store new information. It is often used by R&D personnel who frequently change the micro programs to test the efficiency of the computer system with new programs. It is two types. Ultra Violet EPROM (UVEPROM) Electrically EPROM (EEPROM) Basic of Computer & 'C' programming
Unit 1 PRIMARY STORAGE DEVICES LECTURE – 7 Cache Memory:- is an extremely fast, small memory between CPU and main memory whose access time is closer to the processing speed of the CPU. It acts as a high speed buffer between CPU and main memory and is used to temporarily store very active data and instructions during processing. Basic of Computer & 'C' programming
Secondary Storage Device The Secondary storage of a computer system is non volatile, and has low cast bit stored but it generally has an operating speed far slower than that of the primary storage. The primary storage of a computer system has limited capacity and volatile. Hence, additional memory called auxiliary memory or secondary storage is used with operating system. Basic of Computer & 'C' programming
Secondary Storage Device Sequential and Direct-Access Devices.- A sequential-access storage device is one in which the arrival at the location designed may be preceded by sequencing through other locations so that access time varies according to location. On the other words, information on a sequential-access device can only be retrieve in the same sequence in which it is stores sequential processing is quite suitable for such application like preparation of monthly pay slips or electricity bill. Magnetic tape is an example of a sequential access storage device. Basic of Computer & 'C' programming
Secondary Storage Device Direct-access devices are also called random-access devices because the information is literally available at random i.e it is available in any order. Hence, a random access storage device is one in which any location in the device may be selected at random, access to the information stores is direct and approximately equal access time is required for each location. CD is the best example of Direct access device. Basic of Computer & 'C' programming
Secondary Storage Device Thanks Basic of Computer & 'C' programming