Read-only memory - Revision history

Jnc: minor rectification, better cat

2022-04-26T10:58:01Z

minor rectification, better cat

← Older revision		Revision as of 10:58, 26 April 2022
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	'''ROM''' is simply '''Read Only Memory'''.		'''ROM''' is simply '''Read Only Memory'''.

	Unlike [[RAM]], ROMs cannot be written to. ROMs are also typically slower than RAM.		Unlike [[Random Access Memory\|RAM]], ROMs cannot be written to. At one point, ROMs are also typically slower than RAM.

	ROMs come in several flavors:		ROMs come in several flavors:

	== PROM ==		== PROM ==
	PROMs can be programmed ONCE then read many times. If there are any mistakes in the PROM code, the entire chip must be discarded. While PROMs can be read in a normal board, they need to be programmed in a special device.
			PROMs can be programmed ONCE then read many times. If there are any mistakes in the PROM code, the entire chip must be discarded. While PROMs can be read in a normal board, they need to be programmed in a special device (since programming them often requires special [[voltage]]s).

	== EPROM ==		== EPROM ==

	[[Image:M27C512 EPROM.jpg\|150px\|right\|An EPROM]]		[[Image:M27C512 EPROM.jpg\|150px\|right\|An EPROM]]
	EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. EPROMs need to be programmed in a special programmer.
			EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. EPROMs also need to be programmed in a special programmer.

	== EEPROM ==		== EEPROM ==
	EEPROMS can be erased electronically, and ~~reprogrammed~~ through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be ~~rewritten~~ in-circuit.
			EEPROMS can be erased electronically, and re-programmed, usually through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs, EEPROMS can be re-written in-circuit.

	==External links==		==External links==
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	* [http://madrona.ca/e/corerope/index.html Core Rope & Woven-Wire Memory Systems]		* [http://madrona.ca/e/corerope/index.html Core Rope & Woven-Wire Memory Systems]

	[[Category: Basics]]		[[Category: Computer Basics]]

Jnc: /* External links */ +1

2021-03-14T23:30:03Z

External links: +1

← Older revision		Revision as of 23:30, 14 March 2021
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	== EEPROM ==		== EEPROM ==
	EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.		EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.

			==External links==

			* [http://madrona.ca/e/corerope/index.html Core Rope & Woven-Wire Memory Systems]

	[[Category: Basics]]		[[Category: Basics]]

Jnc: +cat

2018-12-16T23:28:07Z

+cat

← Older revision		Revision as of 23:28, 16 December 2018
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	== EEPROM ==		== EEPROM ==
	EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.		EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.

			[[Category: Basics]]

Jnc: bold name targets

2016-03-20T02:29:54Z

bold name targets

← Older revision		Revision as of 02:29, 20 March 2016
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	ROM is simply Read Only Memory.		'''ROM''' is simply '''Read Only Memory'''.

	Unlike [[RAM]] ROMs cannot be written to. ROMs are also typically slower than RAM.		Unlike [[RAM]], ROMs cannot be written to. ROMs are also typically slower than RAM.

	ROMs come in several flavors:		ROMs come in several flavors:
Line 13:		Line 13:

	== EEPROM ==		== EEPROM ==

	EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.		EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.

Tor: Typo fix: then -> than

2016-02-10T11:12:46Z

Typo fix: then -> than

← Older revision		Revision as of 11:12, 10 February 2016
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	ROM is simply Read Only Memory.		ROM is simply Read Only Memory.

	Unlike [[RAM]] ROMs cannot be written to. ROMs are also typically slower ~~then~~ RAM.		Unlike [[RAM]] ROMs cannot be written to. ROMs are also typically slower than RAM.

	ROMs come in several flavors:		ROMs come in several flavors:

Tor: Fixed some typos and inconsistencies, and updated the part about EEPROMS (they _can_ be updated in-circuit)

2012-11-21T07:08:32Z

Fixed some typos and inconsistencies, and updated the part about EEPROMS (they _can_ be updated in-circuit)

← Older revision		Revision as of 07:08, 21 November 2012
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	== PROM ==		== PROM ==
	~~PROM's~~ can be ~~programed~~ ONCE then read many times. If there is any mistakes in the PROM code, the entire chip must be ~~disgarded~~. While PROMs can be read in a normal board, they need to be programmed in a special device.		PROMs can be programmed ONCE then read many times. If there are any mistakes in the PROM code, the entire chip must be discarded. While PROMs can be read in a normal board, they need to be programmed in a special device.

	== EPROM ==		== EPROM ==
	[[Image:M27C512 EPROM.jpg\|150px\|right\|An EPROM]]		[[Image:M27C512 EPROM.jpg\|150px\|right\|An EPROM]]
	EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. ~~EPROM's~~ need to be programmed in a special programmer.		EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. EPROMs need to be programmed in a special programmer.

	== EEPROM ==		== EEPROM ==

	EEPROMS can be erased electronically, and reprogrammed. ~~While similar to [[Flash Memory]], however they need to~~ be ~~erased & programmed~~ in ~~a special programmer~~.		EEPROMS can be erased electronically, and reprogrammed through the application of higher than normal voltage. In modern EEPROMS this is generated internally. Unlike EPROMs EEPROMS can be rewritten in-circuit.

Neozeed: /* EPROM */

2009-10-08T20:24:12Z

EPROM

← Older revision		Revision as of 20:24, 8 October 2009
Line 9:		Line 9:

	== EPROM ==		== EPROM ==
			[[Image:M27C512 EPROM.jpg\|150px\|right\|An EPROM]]
	EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. EPROM's need to be programmed in a special programmer.		EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. EPROM's need to be programmed in a special programmer.

Neozeed: lame explination of rom's.

2009-03-03T15:14:36Z

lame explination of rom's.

New page

ROM is simply Read Only Memory.

Unlike [[RAM]] ROMs cannot be written to. ROMs are also typically slower then RAM.

ROMs come in several flavors:

== PROM ==
PROM's can be programed ONCE then read many times. If there is any mistakes in the PROM code, the entire chip must be disgarded. While PROMs can be read in a normal board, they need to be programmed in a special device.

== EPROM ==

EPROMs can be erased after they have been programmed. Normally there is a small window in the chip in which exposure to UV light will erase the EPROMs programming. EPROM's need to be programmed in a special programmer.

== EEPROM ==

EEPROMS can be erased electronically, and reprogrammed. While similar to [[Flash Memory]], however they need to be erased & programmed in a special programmer.