ROM

Read Only Memory or ROM is one of the storage memory used in computers and other electronic devices. The data in the read only memory cannot be modified or edited. It is used in software that accompanies computer hardware. A particular data is made and stored in the hardware with no chance of further editing.

Types of ROM

Other non-volatile read only memory types would include Erasable Programmable Read Only Memory, Electrically erasable programmable read only memory or Flash Read Only Memory. The EEPROM could have two types of interface types namely Serial Bus and Parallel Bus. PROM Programmer is used to make Programmable Read Only Memory or One time programmable ROM. PROM Programmer uses high voltage which disables internal links within the chip.

The functions of ROM

While being written, electrons are forced through a layer of electrical insulation. So ROM could be written and erased only for a limited number of times. The endurance and Data retention of different types of Read Only memory is limited. Some of the Read Only Memory could withstand 1000 writing cycles. The contents in Read Only Memory of Game Consoles could be extracted with appropriate hardware or software. Read Only memory is made of components such as BIOS, bootstrap loader, CMOS Setup and Power On Self Test. BIOS controls the input and output of the system. Bootstrap loader helps the RAM to be launched in the operating system. CMOS Setup helps in the screen display. When the system is booted, a program known as ‘Power on Self test’ runs automatically.

Activities of ROM

There are two types of Speed in the read only memory. They could be the reading speed and the writing speed. The content of Read Only Memory is transferred to Random Access memory. Thus Read Only Memory could be shadowed. The ROM types that are electrically modified have a slower writing speed compared to the reading speed. ROM and flash technologies could be found in embedded systems. Since any computer needs memory to record changes, Read Only Memory serves the purposes. Read Only Memory is found in home appliances and consumer electronics. Read Only Memory enables information security by allowing binary storage of cryptographic data which is could not be replaced easily.

In the Programmable Read Only Memory, each bit is locked by a fuse or antifuse. Such Read Only Memory stores programs permanently. They are used in Game Consoles, Mobile Phones, Radio Frequency Identification Tags and High Definition Multimedia Interfaces.

Questions:

• Where are PROM used?
• What are the two types of interface in EEPROM?