Read-only memory (ROM) is a type of storage medium that permanently stores data on personal computers (PCs) and other electronic devices.
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Added: Sep 07, 2019
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R O M Read Only Memory
Read-only memory (ROM) is a type of storage medium that permanently stores data on personal computers (PCs) and other electronic devices. What is ROM?
It is type of internal memory . The data and instructions in ROM are stored by the manufacturer at the time of its manufacturing. This data and programs cannot be changed or deleted after wards. The data or instructions stored in ROM can only be read but new data or instructions cannot be written into it. This is the reason why it is called Read Only Memory.
There are five basic ROM types: ROM - Read Only Memory PROM - Programmable Read Only Memory EPROM - Erasable Programmable Read Only Memory EEPROM - Electrically Erasable Programmable Read Only Memory Flash EEPROM Memory Types of ROM
ROM stores data and instructions permanently. When the power is turned off, the instructions stored in ROM are not lost. That is the reason ROM is called non-volatile memory. Why ROM is non-volatile?
PROM PROM stands for Programmable Read Only Memory. This form of ROM is initially blank . The user or manufacturer can write data/program on it by using special devices. However, once the program or data is written in PROM chip, it cannot be changed . If there is an error in writing instructions or data in PROM, the error cannot be erased rather PROM chip becomes unusable.
EPROM EPROM stands for Erasable Programmable Read Only Memory. This form of ROM is also initially blank . The user or manufacturer can write program or data on it by using special devices. Unlike PROM, the data written in EPROM chip can be erased by using special devices and ultraviolet rays. New data can also be added . When EPROM is in use, its contents can only be read.
EEPROM EEPROM stands for Electrically Erasable Programmable Read Only Memory. This kind of ROM can be written or changed with the help of electrical devices. So data stored in this type of ROM chip can be easily modified.
Flash Memory Flash memory is an electronic non-volatile computer storage medium that can be electrically erased and reprogrammed . Introduced by Toshiba in 1984, flash memory was developed from EEPROM (electrically erasable programmable read-only memory).