Electrical Engineering Stack Exchange
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Questions tagged [eeprom]

Acronym: Electrically Erasable, Programmable Read-Only Memory. Sometimes used with Flash parts that are similar to old EEPROM parts.

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EEPROM is a "Read Only Memory," so why can I write to it?

Electrically Erasable Programmable Read-Only Memory (EEPROM): If it's using Read-Only Memory (ROM) then how am I able to write to it?
Jacksonkr
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Do EEPROMs lose their data over time?

For example 8x8 small image stored on eeprom will get corrupt over time? I've seen somewhere eeproms losing their data over time like vhs tapes.
ihatemyself
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Erasing EPROMs with sunlight

I have heard (I'm not sure how valid it is) that EPROMs could be erased by exposure to UV light. My professor had mentioned it in my Microprocessor Design class; however, I'm not sure if he's bluffing or not. Can anyone verify if this is true? If…
Ci3
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2K EEPROM has only 1K?

Using Microchip EREPROM 24AA02E48. Datasheet says it is a "2-Kbit I2C Serial EEPROMs". In my eyes, 2KBits/8 = 256 Bytes. Storage is addressed in what they call "words", addressable range is 256 bytes wide, ok so far. Storage only allows R/W access…
Michael Schmelz
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Difference between EEPROM types

I was wondering what the difference between EEPROM types are. For example 24S128 and 24LC128. My understanding is that typically the later digits, 128 in this case, represent the amount of space available on EEPROM. But what does the 24 and the…
moesef
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What's a good EEPROM replacement for a 27C256/29C256?

I teach a hands-on computer architecture course in which the students burn their programs onto an EPROM with a commerical PROM burner. The instructions are read by a low-speed TTL computer they build. I started with the 27C256 EPROM but switched…
Ellen Spertus
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Will reading EE/E/PROM wear it out?

After reading some answers on SuperUser, I started thinking: Can EE/E/PROM be damaged by only reading it, with no writing at all? I've read several datasheets for EEPROMS and products that contain them and all I've ever seen were write and erase…
AndrejaKo
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Do eeprom page writes always cost the same time as byte writes?

Some EEPROMs provide the possibility of a multi-byte write. For example, the AT24C provides an 8-byte page write besides the classical single-byte write. The datasheet specifies 5 ms as "Write Cycle Time". However, nowhere is it said that this is…
vsz
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Checking EEPROM for corruption / methods to avoid corruption

When working with EEPROM I'm working on developing methods to expand the life of the EEPROM as long as possible but also checking it for corruption and doing everything I can to avoid corruption upon several occurrences that may happen on a daily…
Matt
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Assembling a .hex file for EEPROM using ASM68K.exe

I know this is a long shot but my college is closed at the moment so i’ll ask here for now. For my senior lab we are asked to program a 28C16A EEPROM. What is expected to go on this EEPROM is incredibly simple. It’s just a truth table with 10 or so…
BobaJFET
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How to program i2c eeprom by hand?

I have a 24c02 eeprom and I want to program it. But I don't have Arduino or any microcontroler. I saw a video about program eeprom by hand, but they are parallel eeprom. This is the link of that video: https://www.youtube.com/watch?v=BA12Z7gQ4P0 I…
Guest
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For maximum EEPROM readability into the future is it better to write once and leave it, or periodically "refresh"?

What is the best strategy if I have a static value that I want to store in EEPROM once and then be able to read it as far into the future as possible? Is it better to write it one time and never write to it again, or is it better to periodically…
bigjosh
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Why Flash memories have less P/E (Program / Erase) cycles (e.g. 100K) compared to EEPROM (e.g. 1000K)?

As per datasheet of EEPROM: CAT24C02 (On Semiconductors) - P/E Cycle count is > 1000k whereas as per datasheet of NAND Flash: MX30LF2G18AC-TI (MXIC) - P/E Cycle count is > 100k I would like to know why there is such high difference in P/E cycle…
Akky
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Why is so8 test clip causing read errors with 93C56 eeprom (TL866 programmer)?

I am trying to read an Atmel 93C56B eeprom, so8 surface mount package, with this programmer. When using the so8 adapter in the zif socket it works perfectly. However when I use the test clip, it is giving me read errors on every other bit. The…
chuck333
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Storing An Led's Previous state when power is removed with eeprom now

A while ago I asked a question about having 2 push buttons, and an LED and you set the led to an on or off state with the two buttons, and then remove the power, and when turned back on, the led should stay in the state that was set when the power…
skyler
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