Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Comparison between different types of ROMs

A prezi for 1st Semester Project's Presentation.

Rubba Rehman

on 4 January 2013

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Comparison between different types of ROMs

EEPROMs are changed 1 byte at a time, which makes them versatile but slow. In fact, EEPROM chips are too slow to use in many products that make quick changes to the data stored on the chip.
Flash memory, uses in-circuit wiring to erase by applying an electrical field to the entire chip or to predetermined sections of the chip called blocks. Flash memory works much faster than traditional EEPROMs because it writes data in chunks, usually 512 bytes in size, instead of 1 byte at a time. Speed.. EPROM chips differ from ROM chips in that they can be rewritten. Much like other ROM chips, they have a grid that communicates binary data when read by an electrical charge. However, while ROM can only be programmed once and is from then on unalterable, EPROM is erasable and can be reused. The erasing procedure entails removing the EPROM chip from the computer and applying ultraviolet light with a special tool. Once the chip is erased, it can be reprogrammed any number of times. EPROM and Rom chips Think for a moment..
What do you look for when you go out to buy a certain product?
Latest Trends? Efficiency? Speed? Reliability? Cost effectiveness?
Yes, you got that right!
These are the factors that form the basis of difference between the ROMs too. The difference lies here! EPROM is a special type of memory that retains its contents until it is exposed to ultraviolet light. The ultraviolet light clears its contents, making it possible to reprogram the memory. To write to and erase an EPROM, you need a special device called a PROM programmer or PROM burner. Erasable Programmable rom (eprom) Acronym for read-only memory, computer memory on which data has been prerecorded. Once data has been written onto a ROM chip, it cannot be removed and can only be read.
Unlike main memory (RAM), ROM retains its contents even when the computer is turned off. ROM is referred to as being nonvolatile, whereas RAM is volatile.
Most personal computers contain a small amount of ROM that stores critical programs such as the program that boots the computer. In addition, ROMs are used extensively in calculators and peripheral devices such as laser printers, whose fonts are often stored in ROMs What is a rom? EPROMs require dedicated equipment and a labor-intensive process to remove and reinstall them each time a change is necessary. Also, changes cannot be made incrementally to an EPROM; the whole chip must be erased. Electrically erasable programmable read-only memory (EEPROM) chips remove the biggest drawbacks of EPROMs.
In EEPROMs, the chip does not have to removed to be rewritten
and entire chip does not have to be completely erased to change a specific portion of it. Also, Changing the contents does not require additional dedicated equipment.
Instead of using UV light, you can return the electrons in the cells of an EEPROM to normal with the localized application of an electric field to each cell. Cost effectiveness.. PROMS are more fragile than ROMs. A jolt of static electricity can easily cause fuses in the PROM to burn out, changing essential bits from 1 to 0. . An EPROM that is left under too long can become over-erased.
Instead of using UV light, the electrons in the cells of an EEPROM can be returned to normal with the localized application of an electric field to each cell. This erases the targeted cells of the EEPROM, which can then be rewritten. EEPROMs are changed 1 byte at a time, which makes them reliable but slow. Reliability.. The EPROM grid is different than ROM grids because it has two transistors at each intersection; one is called the floating gate, and the other is called the control gate. When a charge is sent, the floating gate acts like an electron gun, creating negatively charged electrons where a cell sensor monitors their charge. The data value is determined by the amount of current passing through the gate: More than 50 percent reads as a one, and less than 50 percent reads as a zero  EPROM and Rom grids Didn’t figure out yet?
Let us make it easier for you! Where does the difference lie? A special type of ROM that can be erased and reprogrammed in blocks instead of one byte at a time. Many modern PCs have their BIOS stored on a flash memory chip so that it can easily be updated if necessary. Such a BIOS is sometimes called a flash BIOS. Flash memory is also popular in modems because it enables the modem manufacturer to support new protocols as they become standardized. Flash memory EEPROM is a special type of PROM that can be erased by exposing it to an electrical charge. EEPROM retains its contents even when the power is turned off. EEPROM requires data to be written or erased one byte at a time . Electrically erasable programmable memory (eeprom) Short for programmable read-only memory, a memory chip on which data can be written only once. Once a program has been written onto a PROM, it remains there forever. Unlike RAM, PROMs retain their contents when the computer is turned off. Programmable rom (prom) Mask programmable read-only memories (ROMs) are the least expensive type of solid state memory. They are primarily used for storing video game software and fixed data for electronic equipment, such as fonts for laser printers, dictionary data in word processors, and sound data in electronic musical instruments. MASK PROGRAMMABLE ROMs(mroms) MROM
FLASH MEMORY Types of roms
PC Rubba Rehman
NS Fatima Ehsan Comparison between different types of roms
Full transcript