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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2k views

I2C EEPROM with non-standard address?

So I know that almost all i2c EEPROM ICs use 0xAh (or 1010) as the top four bits of the slave address. I currently have a 16 kbit EEPROM on my i2c bus that uses the lower 3 bits of the slave address ...
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994 views

Can an EEPROM be one-time-programmable?

I'm confused, and I hope you can help me figuring out, what I misunderstood. I am not an electronics engineer, so bear with me :) I have a chip, from the engine control unit of a Toyota Yaris Verso ...
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USB, UART, SPI difference and usage? [closed]

I am trying to enabling an embedded system built around Intel D1000 MCU. I am mainly from a software background and just starting to catch up with some hardware knowledge. I am trying to build ...
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3answers
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Flash EEPROM Emulation

Given that there are many differences in the way data is written to EEPROM and Flash, how exactly is EEPROM emulation done with internal flash? Also, flash needs to be erased in large blocks before ...
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768 views

Intermittent SPI bus

I'm attempting to interface a PIC18F4520 to a 25LC640 via SPI protocol. I'm using the built in MSSP hardware of the PIC. The PIC18F4520 is the only master on the bus. I'm reading 16 bytes of data from ...
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EEPROM reading and writing

It is known that there are limited read and write cycles for EEPROM. Suppose I keep writing some important information in EEPROM and read it after power off to ON. Suppose at some point of time the ...
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2answers
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CRC for eeprom data check

I wanted to check redundancy in eeprom and crosscheck the data for any errors occurred or not and I ended up reading CRC code. I found it useful but have some doubts that need clarity. My objective ...
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2answers
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Flash/EEPROM endurance

In this answer stevenvh suggests that Flash memory uses the same floating-gate technology as EEPROM. However! Looking at a random AVR datasheet it says for EEPROM 100 000 erase/write cycles, while for ...
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1answer
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Amtel ATtiny EEPROM partially erased on power cycle

I have a Digistump with an Amtel ATtiny85 MCU. I can flash the MCU's EEPROM with an ISP programmer no problem. The chip works fine, the bootloader runs and the user program executes correctly. ...
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3answers
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How to properly use STM32 flash memory as an EEPROM?

I have to save certain parameters to the flash memory and these values should be non-volatile. But my program will change these parameters and I want the changes updated to the flash. I understand to ...
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1answer
452 views

Number of address in AT24C16 EEPROM or is it duplicate?

I am working on EEPROM AT24C16 for a particular project. According to the datasheet it must have 2048 addresses and I should be able to write 1024 unsigned int into it [ 1 unsigned int per 2 addresses]...
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EEPROM Write Cycle Time and Write Cycle Endurance

I have an embedded software application that is copying a buffer from RAM to EEPROM. In this case, the EPROM device is a 28C010 (128K x 8). The copying is done at non-regular intervals, generally in ...
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How to store array of values in EEPROM of ATmega16 and then read it in sequence

I have this program in which I can store a single value in EEPROM. Can I store an array of values in EEPROM? How? ...
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3answers
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the . hex file we burn goes to flash memory or RAM or EEPROM of Atmega8?

The flash memory of atmega8 is 8Kb. Is this the maximum size for the .hex file, or it the max memory which i can allocate to variables in my code? If none of the above is true, than what is memory ...
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Connecting to an EEPROM

I am trying to download the contents of a ROM chip following this tutorial however the chip is surface mounted and I can't remove it to put it in a breadboard. I don't want to solder wires to the ...
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1answer
494 views

Can't read written data out of 24AA1025

I've got a PIC18F with MSSP that I'm interfacing with a 24AA1025. I'm using MPLAB 8 and the functions from C18 to make my life easier. The only problem is that I've (supposedly) written a byte to ...
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2answers
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Advice on suitable SRAM

I'm kind of new to all this and the choices out there is kind of overwhelming when it comes to selecting a SRAM package and Flash eprom to go with a 10 Mhz Z80180. I'm looking for a 128 KB SRAM and a ...
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I need to lock reading my mega328 flash but be able to write to the eeprom

I need to be able to prevent other from copying my program placed in the flash, but want to still be able to write to the EEPROM. I tried the lock bits by setting them to Mode 3 (0x3C). But that will ...
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1answer
972 views

EPROM Replacement Strategies

We have a system that uses OTP (one-time programmable) EPROMs, specifically the AT27C256. We would like to replace this EPROM with an EEPROM or Flash chip such that we can make our units field ...
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1answer
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Problem with I2C EEPROM communication

I have a STM32L MCU connected to M24LR64E, an I2C EEPROM. Previously i had this setup working but then i changed some things (layout, firmware) and somehow i screwed the I2C and it is not working now. ...
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2answers
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High capacity - EEPROM chip

I am looking for high capacity eeprom(I2C compatible) IC as an alternative to 1gb or 2gb micro SD card (data storage segment in my project) just in case I fail to interface Sdcard with pic32 mcu.. ...
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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 ...
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EEPROM data check

I am communicating with an EEPROM chip with micro controller. I am writing certain data in to specific addresses in EEPROM and needs to check the data occasionally. But I have no idea other than ...
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1answer
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What's the difference between 1kb(64x16) and 1kb(128x8) for EEPROM memory size?

In addition to the question in the title, I have the following subquestions: I'm guessing 64x16 means something like 64 cells of 16 bytes each. Is this accurate? What is the significance (if any) of ...
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1answer
222 views

How are system configuration flash or eeprom chips programmed?

I've seen, quite often actually, a circuit that will have an eeprom or flash chip soldered next to the application chip. Take a look at the ESP8266, it has some kind of programmable memory that sets ...
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What's a good EEPROM replacement for a 27C256/29C256? [closed]

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....
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3answers
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Is using memcmp when updating struct in EEPROM okay?

I am writing a generic update function for EEPROM which compares old value with new one and then if values differ writes new one to eeprom. This is the function: ...
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1answer
687 views

EEPROM Emulation driver does not work when Page Sizes are 2KB

I am trying to implement EEPROM Emulation on an STM32F07x using the driver supplied by ST. Problem is on attempting to initialise the emulated flash, the driver fails and always returns NO_VALID_PAGE. ...
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3answers
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How to program EEPROM

In looking for a 64K x 8 Parallel EEPROM, one of the most available chips is the 27SF512. Google would indicate this is commonly used by auto enthusiasts to replace chips in various cars. I have found ...
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How to correctly choose a memory?

I'm about a to choose a chip to store a mp3 file (few mo) in it. But I don't really know how to well choose such a memory. Should I go for a flash memory? Eeprom? Nand? Nor? What kind of parameters ...
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1answer
206 views

How easy to indentify memory like ROM or EEPROM Flash Memory Areas of a Chip

Can anyone tell me would the memory circuit areas (ROM, EEPROM, SDRAM, Flash Memory) of the layers of a die belonging to a MCU and SoC IC's be relatively easy to identify compared to identify circuit ...
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1answer
778 views

27512 pinout and PCB layout

I'm trying to design PCB traces for a 27512 EPROM chip. But its pinout for the higher half of the address bus seems completely illogical to me and I cannot imagine how should I lay out my traces for ...
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2answers
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Will an SPI EEPROM chip have the same issues with non-atomic write operations as a dsPIC's internal EEPROM? [duplicate]

A while back I had some intermittent trouble with the internal EEPROM of a dsPIC. Every so often, some value in the EEPROM would be found zeroed out on power-on. I tracked the problem down to when the ...
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1answer
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AVRDUDE: Write EEPROM bytes without file

Is it possible to write EEPROM bytes via AVRDUDE and an AVRISP mkII directly from the command line without needing an EEPROM file read from another chip? Kind of like how you can specify the fuse ...
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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 ...
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2answers
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Casting integer to character

I am using PIC18f microcontroller. I have to write a 16 bit integer variables (2 bytes) which was cast into two character variable i.e to write each byte in a consecutive adrressess of EEPROM. By ...
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1answer
2k views

eeprom data corruption during power failure

I recently found a problem with eeprom of a PIC16F877A which is used to control the speed of a dc motor. The drive is supposed to work on the last set speed even if the power fails. But the problem is ...
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1answer
243 views

Understanding scrolling display circuit

I have this outline of a circuit designed to display a scrolling message. I'm having some trouble understanding how it's supposed to work, so I'm just going to explain what I think I know and go from ...
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1answer
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EEPROM in beaglebone black

I want to disable EEPROM in beaglebone black by unloading i2c-omap driver. Will it create problem in hardware or any other software support? What should I expect ?
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PIC16F EEPROM write errors

I'm developing on a PIC16F1936 using the MPLAB X IDE with the XC8 complier. I've been given this project where I need to "upgrade" the software of a PCB such that it can interface with an external ...
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1answer
445 views

Programming an 82S23

I have to program an 82S23. There is surprisingly little documentation on how to do this. There are datasheets that will tell you how to read it, but not burn. I built one following these ...
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1answer
424 views

No ACK from I2C EEPROM PIC18F

Im trying to store some data in the 24AA01 EEPROM using the PIC18F13K22. Since I am awaiting the components, I thought I will go ahead and simulate it in Proteus. This is my code (XC8 compiler based)....
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Why fram instead of eeprom

Why do all the gameboy cartridge mods for nonvolatile save use a type of ram like fram? Why isn't a sufficiently fast eeprom or flash ic used? EDIT: We all know this is about parallel interface ICs, ...
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Is the ROM of an MCU NAND FLASH ?

I understand binary code is stored in the ROM area of an MCU. Typically most MCUs have FLASH EEPROMS. Is this really the NAND type FLASH storage we find in most SSDs? If not, what are the ...
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4answers
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EEPROM I2C driver hanged during ESD test?

In our prototype , we have a I2C based EEPROM . During ESD Test(High potential spark is injected into system for a very short moment), the drivers hangs in the I2C code. Basically there are while ...
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2answers
493 views

Device including RTC EEPROM and battery?

I am currently designing an electronic board and i got a question: Do you know if there is any device in which are integrated an RTC, an EEPROM and a battery? I heard about this type of device (i ...
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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 ...
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1answer
129 views

ATTINY84 - EEPROM read cycle time

Thought this was easy, but I can't find this information on how long / how many cycles a EEPROM read operation on an ATTINY84 takes. Page 22 of the datasheet has a table with write and erase times: ...
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1answer
270 views

EEPROM Write Limit [duplicate]

Just curious as to why do non volatile memories like EEPROM in an AVR have a write limit ? Also is this limit per location/adress in the memory or on the memory as a whole ?
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1answer
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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 ...