Types of Read only memory (ROM)
There are mainly three types of ROM:
- PROM (Programmable Read Only Memory)
- EPROM (Erasable Programmable Read Only Memory)
- EEPROM (Electrically Erasable Programmable Read Only Memory)
The only difference between ROM and PROM is that the instructions in ROM are designed by the manufacturer of the computer where as in PROM,the instruction are programmed by the user himself according to his requirement.
PROM is also known as one-time programmable non-volatile memory.
2. EPROM (Erasable Programmable Read Only Memory):
In EPROM, the user can program the instructions himself according to his requirement and later on, he can also erase the instructions by using Ultra-Violet Rays (UV Rays) and i.e. program the new instructions in it.
3. EEPROM (Electrically Erasable Programmable Read Only Memory):
EEPROM such as Flash memory allow the entire ROM to be electrically erased then written to without taking them out of the computer.