Forums Search for: EEPROM
refreshing RAM from EPROM
inI'm working on a project where they implemented a data store in EEPROM and a copy of it in RAM. The RAM copy is updated all the time and a low...
I'm working on a project where they implemented a data store in EEPROM and a copy of it in RAM. The RAM copy is updated all the time and a low priority task writes it back to EEPROM. There is also a task that eery once in a while copies back from EEPROM to it's RAM shadow. I can't understand why someone would want to do that - if it is to overcome corruption, isn't it better to reset the ...
CRC calculation for variables stored in eeprom
inDear all, I have posted a couple of months back about eeprom corruption and some experts here adviced me to stored a CRC value for the...
Dear all, I have posted a couple of months back about eeprom corruption and some experts here adviced me to stored a CRC value for the memory contents to determine corruption.Regarding this I have got a query: In our case,the contents in the eeprom change dynamically in run time.Does that mean everytime we need to update the CRC too?As an end user how would I know which value of CRC is ...
custom VID/PID help
incan anybody help me...? I hv 1 FT232BM chip and EEprom 93lc46. I am configuring my EEPROM using Eprog 3.0 software. In that I do change...
can anybody help me...? I hv 1 FT232BM chip and EEprom 93lc46. I am configuring my EEPROM using Eprog 3.0 software. In that I do change with my own VID and PID both and downloading it to EEPROM. and change the FTdibus.inf / Ftdiport.inf file with both VID and PID. but the problem is everytime my PC detect the same comport COM6 at all my 4 USB ports. but when I erase and set the defaul...
Writing 9 bits in a sequence to perform Soft Reset
Hi all, This is again a follow up on EEPROM discussion I had previously a few days back.Regarding I2C based EEPROM I recently came across...
Hi all, This is again a follow up on EEPROM discussion I had previously a few days back.Regarding I2C based EEPROM I recently came across an application note from Microchip company (Document name AN709). The note says : "FORCING INTERNAL RESET VIA SOFTWARE In all designs it is recommended that a software reset sequence be sent to the EEPROM as part of the microcontrollers power up sequenc...
Problems reading data EEprom on Pic 16F88
inI have been trying to use the read data EEPROM feature of the 16F88, but can't get it to work. I have used the sample code from Microchip's...
I have been trying to use the read data EEPROM feature of the 16F88, but can't get it to work. I have used the sample code from Microchip's datasheet. Attached is the (entire) ASM file that I am using. It should (I had hoped) store the value h'BB' in the register count1. Then read it from the data EEPROM location (h'20') and store it into the register count2. When I step through it in...
Read-While-Write Flash memory
inLinked to my previous post, here I'd like to discuss another topic related to persistent variables. Some years ago I used microcontrollers...
Linked to my previous post, here I'd like to discuss another topic related to persistent variables. Some years ago I used microcontrollers with internal EEPROM memory or I used external serial I2C EEPROM to save persistent variables. It seems to me the scenario has recently changed. With new Cortex-M microcontrollers, internal EEPROM is typically absent, but the manufacturer explain...
EEPROM guarantees after power loss during a write
inHi, I am wondering what guarantees are there for existing EEPROM data, after power is lost during a write operation? I am writing a...
Hi, I am wondering what guarantees are there for existing EEPROM data, after power is lost during a write operation? I am writing a datalogging routine that writes records to an EEPROM. It's an Atmel 24C1024, although the question is probably applicable to other devices too. This uses "page mode" for writes - the device seems to be organised as 256 byte pages. Say power is lost during...
MPC8260 - I2C - single channel 1-wire master (DS2482) - 1 wire EEPROM (DS2433)
inHi, I'm writing an I2C driver for the MPC8260 that needs to read/write to a 1-wire EEPROM via a single channel 1-wire master. Since I'm new...
Hi, I'm writing an I2C driver for the MPC8260 that needs to read/write to a 1-wire EEPROM via a single channel 1-wire master. Since I'm new to the embedded world, I was wondering, if I want to send a READ ROM command to the 1 wire EEPROM, how must I go about doing that via software? How must I format the Tx buffer of the I2C to send that out to the 1-wire EEPROM via the single-channel 1-...
Read EEPROM Memory on a mc9s12dg256 from Motorola
inHi ! I have to write an EEPROM driver for an mc9s12dg256 from Motorola. Everything is fine, but i cant find a command ro read from the...
Hi ! I have to write an EEPROM driver for an mc9s12dg256 from Motorola. Everything is fine, but i cant find a command ro read from the eeprom memory. There are commands for Writing and erasing, but no Command for reading the memory. The Documentation from Motorola is real bad. Please help ! THX
EEPROM cell failures
inHello, does anybody know when an EEPROM cell failure caused by too many writings is detect? when I write a value and immediately after...
Hello, does anybody know when an EEPROM cell failure caused by too many writings is detect? when I write a value and immediately after the writng I read it or after some time? thank you
PIC EEPROM EEIF flag polarity
inJust wondering if someone could suggest a workaround for this snippet of pseudo code: if ( eeif == 1 ) { eeif = 0 // write...
Just wondering if someone could suggest a workaround for this snippet of pseudo code: if ( eeif == 1 ) { eeif = 0 // write eeprom } This piece of code (written in assembly) goes into the main loop of my program and allows the main loop to continue executing while the EEPROM takes its leisurely 8ms to write. The problem is that on power-up eeif == 0, and this code can never ...
eeprom problems
inHi, is there any documents instruct how to read data from eeprom, like 93c46? I have 93c46's datasheet and source code from linux rtl8139...
Hi, is there any documents instruct how to read data from eeprom, like 93c46? I have 93c46's datasheet and source code from linux rtl8139 driver, but I still can not understand the detail.
i2c eeprom.c driver supports 2 address bytes?
inI have a i2c eeprom device (Microchip 24LC65) that has 2 bytes for the device address (this is the 2 bytes that come right after the...
I have a i2c eeprom device (Microchip 24LC65) that has 2 bytes for the device address (this is the 2 bytes that come right after the control byte). The eeprom.c driver seems to handle devices that has only 1 byte for the device address. Has anyone configured the eeprom driver for devices that needs 2 bytes for its addressing? I am working on a IXP425 board. The i2c algo is i2c-algo-bits.c. ...
Why Serial Flash has SPI, but Serial EEPROM - I2C ?
inDear, I'd like to understand why ALL Serial Flash chips always come with SPI vs Serial EEPROM chips that always come with I2C ? Why not vice...
Dear, I'd like to understand why ALL Serial Flash chips always come with SPI vs Serial EEPROM chips that always come with I2C ? Why not vice versa for example? For my current project I'd like to add a small external memory, let's say 16 kBytes, as a backup for some case. Writing to EEPROM is too slow, 5 msec for 8 bytes, wheres Flash is good, but it comes with SPI = 5 PINS: SCK, MISO,MOSI,...
CY7C68013 remove EEPROM
inIs there an easy software way to remove the vid/pid from the EEPROM and ge back to the initial Cypress one? Thanks Eric This...
Is there an easy software way to remove the vid/pid from the EEPROM and ge back to the initial Cypress one? Thanks Eric This message was sent using the comp.arch.embedded web interface o www.EmbeddedRelated.com
PIC 18F4520 SPI with Serial EEPROM
inI am attempting to communicate with a 25LC256 serial (SPI) EEPROM with a 18F4520. I have successfully communicated with this same EEPROM with...
I am attempting to communicate with a 25LC256 serial (SPI) EEPROM with a 18F4520. I have successfully communicated with this same EEPROM with a 18F4431 using the same code. The code I am using is as follows: MEM_CS = 0; SSPBUF = 0x02; while(SSPSTATbits.BF != 1); SSPBUF = AddressHigh; while(SSPSTATbits.BF != 1); SSPBUF = AddressLow; while(SSPSTATbits.BF != 1); SSPBUF = DataByte; ...
Reading EEPROM data, ATMEGA16, with imagecraft c-compiler
inHei all, The intension is to read out a table located in EEPROM using the imagecraft C-compiler version 6.31A Definition in...
Hei all, The intension is to read out a table located in EEPROM using the imagecraft C-compiler version 6.31A Definition in C --------------- #pragma data:eeprom char Output_Ports_Table[] = { 0x38, 0x02}; #pragma data:data .. .. In the program i write following code ... ... unsigned char Table_Contents; EEPROM_READ((int)&Output_Ports_Table[0], Table_Contents); Tab...
question on ARM comparing to AVR
inI have experience developing 8051 but I'm very new to ARM comparing to AVR. My question is how ARM save data since it doesn't have built in...
I have experience developing 8051 but I'm very new to ARM comparing to AVR. My question is how ARM save data since it doesn't have built in eeprom like AVR? I checked many ARM eval board but they all don't have external eeprom. I found a ARM board that completely suit my needs but it doesn't have eeprom. I would think this is normal to every ARM and am I missing something? thanks for an...
Xicor X28HC256 EEPROM
inHi, can anybody tell me where to find more internal information about the Xicor X28HC256 EEPROM than in the normal product data sheet? I'm...
Hi, can anybody tell me where to find more internal information about the Xicor X28HC256 EEPROM than in the normal product data sheet? I'm especially interested in the page write operation. Is there an internal RAM in this EEPROM which stores the incoming data until the page write operation starts? If this is true, does the page write cycle write the data bytes starting from higher address...
Help new bie in TMS320LF2407A DSP programming
inHello ALL I am new DSP programming & Code composer. I have to build a windows application which communicates with TI DSP by RS 232 PORT. TI DSP...
Hello ALL I am new DSP programming & Code composer. I have to build a windows application which communicates with TI DSP by RS 232 PORT. TI DSP is connected with a EEPROM 25LC050 through SPI. Windows application sends data to DSP and ask it to save some data to EEPROM. Windows application can also ask DSP to retrive data from EEPROM. Also I have to code for TI DSP(model TMS 320LF2407A) th...