EEPROM Help needed

[Pje]

Hi All,

Please I need some explenations regarding EEPROM (with SPI interface) .The SPI is working I can see the signals on my LA ,

However I have some very basic questions regarding the EEPROM 256Kx8 page size according to the datasheet is 64 bytes per page .My questions are reality very basic however googling did not realy help .

1- does the 16 bit addresses start at 0x0000 and then incerement by 1 so next will be 0x0001 and so on until byte 63 which is then the address 0x03F 

2- does the 2nd page then start at 0x0040 ? and at  0x00FF I would be at the end of page 4 ?

3- is there some visual repersentation that I can view to see this memory map clearly in my head ?

4- If I write 10 bytes in one go start at address x do I need  to have some delay between the write of the bytes or can I just clock then out one after the other the datasheet mention something about 5mSec write delay does this delay means beween bytes?

I applogize for these elementary questions however it is my first time working with an EEPROM 

Any help hints would be appreciated 

Regards 

[SofLit]

Hello,

You didn't mention what EEPROM part number you are referring to?

[Pje]

HI Sorry for that it is a P25C256F from PUYA semiconductor 

http://www.easygood.hk/Pro_show.asp?id=73

Thanks again for any help 

[Andrew Neil]

They seem to have forgotten to link to the datasheet from that page!

so Google finds it here: 

https://www.puyasemi.com/download_path/%E6%95%B0%E6%8D%AE%E6%89%8B%E5%86%8C/EEPROM%20%E8%8A%AF%E7%89%87/P25C256F_Datasheet_V1.3.pdf

That should answer your questions

[Pje]

Hi all,

Dear Andrew Thank you that sure helped in many ways, 

I managed to sort out how the addreses and page boundries are formulated and I can write a number of bytes(10) to a certain address location and read them back , some progress made .

I noticed and as mentioned in the Datasheet when writing to a page it is possible to start at the first address of the page and write 64 bytes to that page if more is written then the internal counter rolls back to the start of that particular page and the previous data is over written. 

My lack of  of knowldge is letting me down, I am unsure how to detect in the code that I need to shift one page up if 64 bytes are reached, sorry if my writing makes no sense. 

I need to write about 320 bytes of data which is in my understanding is 5 pages of the EEPROM Memory.

Any code examples or advise will be highly appreciated .

Best Regards Pje

[MM..1]

Why yoou dont use internal Flash emulation EEPROM in F1? 

[Pje]

Simply because I am not the person who designed the Hardware 

Thanks for your question

I found a tutorial that deal with my issue directly from Controller Tech, Thanks in any case for the people who tried to help me 

[Andrew Neil]

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@Pje wrote:

I found a tutorial that deal with my issue directly from Controller Tech, Thanks in any case for the people who tried to help me 

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Please give a link, and/or describe  how you resolved the issue, then mark that post as the solution - that way, future readers can learn from you:

https://community.st.com/t5/community-guidelines/help-others-to-solve-their-issues/ta-p/575256

[MM..1]

Question isnt who design hardware, but if your software can use internal flash for store required info or your design require external hw . If A is right simply dont solder B ...

[Pje · Accepted solution]

Here are the link to the block post about EEPROM writes and the address /page issues

https://controllerstech.com/eeprom-and-stm32/