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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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9answers
1k views

EEPROM with high endurance

I am currently working on one embedded project in which I have one counter which will be active all the time. If the power goes down then also I have to store last counter status and load it back in ...
7
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3answers
569 views

Why is there a maximum time for length of write pulse to write on an EEPROM?

I am still just learning about electronics on my own, so please bear with me. The EEPROMs that I have come across (for example this one where the t_wp max is 1000 ns.) all have a time limit for the ...
2
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1answer
140 views

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 ...
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2answers
135 views

AT28C16 Interface Help

I pulled an AT28C16 from an old KVM switch and have managed to wire it up like so: A0-10 -> GND CE -> GND WE -> 5V OE -> GND VCC -> 5V GND -> GND I/O0-7 -> Floating. Plugged by hand to level meter ...
0
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1answer
508 views

What data is stored in an eeprom that’s not in the flash memory? [closed]

I’m wondering generally what information is stored in an eeprom that’s different than what’s in the flash drive that contains firmware? Mostly in mobile devices. Does the eeprom contain user settings ...
0
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1answer
62 views

What Happens if a Device Is In a Device Tree but Not Physically Present

Probably a very newbie question: I have a Zynq 7100, zc706 board. I am playing around with the ARM Processing System with Xilinx's PetaLinux distro. What would happen if I added a device to the ...
0
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1answer
45 views

EEPROM dublicate pages

I'm facing a strange issue. Whenever I write to my EEPROM (24LC04B), it gets written to every other page as well and I can't understand why. i2cdetect -y 1 returns 8 pages: ...
5
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1answer
244 views

What is wrong with my eeprom?

I am using an eeprom M24C32-W from ST. Here is my schematic with VCC=3.3V. The write protection Write Control pin is connected to VSS and thus should be disabled. The address of the device is 0xA0 (or ...
0
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1answer
146 views

Increase EEPROM capacity and data lines

Question: I need to increase the capacity and data lines of a EEPROM board using decoder and/or basic logic gates. The EEPROM is Hitachi HN58C1001. it is 128K by 8 bits. Task is to make it 1M by 32 ...
0
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1answer
231 views

are 100K resistors too weak for connecting HC to cmos?

I have created two identical circuits. The only difference between them apart from the number of lines on the LCD is that the old circuit uses 10K pull-up resistors instead of 100K pull-up resistors. ...
0
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2answers
148 views

SPI timing of 25LC1024

I'm using an EEPROM chip from microchip, it's doc gives the read/write timing as below: I'm a little confused. From FIGURE 1-2, I think it will read data in at the rising edge of SCK. But from FIGURE ...
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2answers
156 views

nxp microprocessor ethernet socket coding and sending code [closed]

I have nxp lpc43s50 microprocessor and I made an ethernet connection via lan8710 and at24c02 .I know how to connect at24c02 to my microprocessor pins .However I don't know how to send codes to my ...
2
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0answers
265 views

Problem with writing eeprom memory

I am trying to write atmel at28c256 on breadboard so I tied all address lines to ground, and all I/O lines also tied to ground. I untie I/O lines for reading, tie 'WE to high, 'CE to low, and 'OE to ...
0
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3answers
394 views

Can I read EEprom in circuit when connected to a SH7055 MCU?

I am trying to read a microwire 93C66 EEprom which is connected to a Hitachi SH7055 MCU. The device is a complete automotive ECU. I need to be able to do this in circuit. Currently I get an error ...
0
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2answers
491 views

Purpose of Pullup Resistor for Active low pins in EEPROM

I am working with a 25LC640A EEPROM, which is having active low control Pins like CS,Hold,wp (Write Protect). I have Connected Pull up Resistor for CS only alone. Its working fine. Please refer the ...
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3answers
484 views

EEPROM Values Corruption - Only Some times

I am using 25LC640A EEPROM with a 32 bit Micro controller. This EEPROM can store 8kb of data, with SPI serial Communication. In my case during every power down sequence MCU will write some block of ...
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1answer
70 views

How to select specific programmer from multiple when using flashrom

I have 4 CH341A programmers connected to my laptop. They are all connected to the same USB hub. Reading the content of a SPI EEPROM works fine. How do I select the programmer (of these 4) to be used ...
3
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2answers
2k views

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 ...
1
vote
1answer
210 views

I2C-ATMEGA328p as Master and 24LC256 as slave

So i am trying to establish a connection between ATMEGA328p as Master and 24LC256 EEPROM Chip using I2C protocol. Clock is set to 100KHz SDA and SCK lines are pulled up to Vcc using 4.7K Ohm ...
3
votes
2answers
396 views

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 ...
0
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1answer
233 views

What is paging in EEPROM?

I have two questions regarding paging in EEPROM here: What is paging in EEPROM? In what situations is it normally used? If you can provide an example with the AT24CXX that would be much ...
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0answers
140 views

Microcontroller(Atmega16A) hangs in Stop method while communicating using I2C with Atmega16 and 24LC256

First of all let me say that I am a beginner in embedded programming. I am trying to do write/read using I2C protocol from 24LC256 EEPROM using Atmega16A. While debugging in Atmel Studio 7, I see I ...
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3answers
104 views

How to build a larger ROM using smaller parts?

How can i build a 1024-bit ROM using 512-bit and smaller ROM's? Is it good idea to use a 2:1 MUX and that selects on of 2 512-bit ROM's?
0
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1answer
229 views

Disable writing to Winbond EEPROMs

A common type of EEPROM used in computers is the Winbond chips, such as W25X10A, W25X20A, W25X40A, and W25X80A. The datasheet for these chips can be found on Datasheet archive. It was not clear to me ...
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2answers
193 views

Shift address of eeprom? [closed]

I'm working with a device that reads and writes to an eeprom via I2C. It automatically uses a starting address at the bottom (beginning) and I cannot change this. But this device uses a fairly small ...
0
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1answer
75 views

Proper way of handling fonts in memory

I'm making a very simple terminal. It consists of ATMEGA328, which outputs text on an LCD represented by the fonts read from the EEPROM (24LC). Each character of the font consists of 9 bytes (each ...
1
vote
1answer
244 views

Are EEPROM chips getting obsolete?

I am making a circuit with a microcontroller that has a periodic need to save about 500 bytes of information in a non-volatile storage. Running only on a supercap that might be charged up rarely, the ...
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0answers
150 views

Replacing SD card by using EEPROM

I am using the mbed platform and to be specific, NUCLEO L073RZ. To log data, I am using SDFileSystem.cpp that is officially supported by mbed (you can find the link ...
0
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2answers
627 views

Cost and Power of EEPROM and Flash? [closed]

I am working on a project which requires low power persistent storage. It needs to store 1 kB of data at most. The data is organized in blocks logically. So, a update of one block requires 100 B to be ...
2
votes
1answer
114 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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2answers
78 views

Separate calibration values from program

I am working on a device with an internal pump. Due to small differences in the pump's motor speed, I have to calibrate the pump. The result is a value between 0 and 1 (PWM duty cycle). The PWM is ...
0
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2answers
359 views

what is the EEPROM (28C64) output behavior between address change?

I wrote all "1"s into a 28C64 EEPROM from address 0 to 15 (the rest address lines tied to GND). Then I use a 4-bit counter (10HZ clock) to drive the address lines from 0 to 15 to read the 28C64. I ...
0
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1answer
300 views

Using EEPROM insted of flash in AVR?

I am writing one AVR Mikrobasic Program which my Atmega32 flash memory is fulled. Can I use EEPROM space for saving my functions routines instead of flash memory for releasing some space of flash ...
1
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1answer
209 views

M24LR16-E I2C EEPROM not detected during I2C scanning device

I am using the M24LR16-E EEPROM which is an I2C device: http://www.st.com/content/ccc/resource/technical/document/datasheet/56/58/3c/91/80/a4/49/89/DM00031737.pdf/files/DM00031737.pdf/jcr:content/...
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1answer
38 views

Power Fail Monitor and ADC measurement

In my AVR project, I need to measure input voltage (before buck converter), and check for power loss to quickly save some data to EEPROM. Measuring input voltage is just to display its value, but I ...
3
votes
3answers
261 views

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: ...
2
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2answers
658 views

How to repeatedly read and write a SMD EEPROM without unsoldering it each time?

I am doing a lot of reverse engineering on SOIC-8 Eeproms in automotive ecus. At the moment it requires unsoldering the chip, read/write, solder the chip back in, test, repeat. Most Eeproms have to ...
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1answer
1k views

When to re-enable WP pin on EEPROM?

I am using STM32F4 microcontroller and 24AA512 EEPROM, which uses I2C to communicate with MCU. Like many EEPROMs it has W(rite) P(rotection) pin and I want to use it because why not. But there is one ...
3
votes
1answer
374 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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1answer
172 views

simplify external I/O memory access with small micro

I was reading atmel's AT28C256 datasheet and it states for a write operation: A low pulse on WE or CE input initiates a write cycle. The address is latched on the falling edge of WE or CE whichever ...
0
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3answers
160 views

Algorithm for testing EEPRM

What are the steps or the algorithms to verify that an EEPROM is working ? Right now I just write 10 bytes and I read 10 bytes from 10 addresses, and that's naïve approach. Is there an algorithm or ...
1
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1answer
235 views

Reading and Writing to FRAM fails

I'm using the following eeprom FM25CL64 http://www.tme.eu/at/Document/f170062ad2f9464359d3dc53837256d8/fm25cl64ds_r3_2.pdf I try to write data, read data by polling but it stays in infinite loop and ...
0
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1answer
428 views

Steps for testing external flash memory [duplicate]

I have a blackfin 533 and I connect it with external flash memory. I have a software driver that erases a block, fills data, write to flash memory. I'm using the following chip ST M29W800D. How ...
0
votes
1answer
102 views

Why do parallel memory chips in a DIP package have a disorganized pin arrangement? [duplicate]

I'm looking at datasheet for old RAM's and EEPROMS, and one in particular I'm using is part AT28C256. Why is it that the order of the address lines do not correspond with the actual pin number. An ...
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1answer
1k views

How to test flash memory

I'm using blackfin533, and I would like to write a software for flash memory testing. How would I test the flash memory ? I know how to test an eeprom but how would I test the flash memory of the ...
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1answer
279 views

eeprom overflow

I was using STM32f401RE,and i stored a series of numbers into the AT24c512, EEPROM read and write operations on several times during the implementation of the code is done, about 10,000 times each ...
1
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1answer
153 views

How to count EEPROM wear cycles when flipping an address back and forth?

I'm trying to determine the life of some EEPROM. I will be erasing a byte (setting to 0x00, clearing a parity bit) as frequently as I will be writing to it. So if setting it to 0x00 counts as a wear ...
0
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1answer
79 views

Reading from EEPROM problem [closed]

I write a structure into EEPRM as follows ...
1
vote
1answer
47 views

Programmatically verifying EEPROM pins connected

I can't find really much about it online, but am curious if there is any bit-fiddling like tricks to verify all pins on a EEPROM are properly soldered/connected (particularly address pins on a ...
5
votes
3answers
5k views

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 ...