EEPROM data writing problem

[Vikas Agrawal]

Posted on February 17, 2017 at 12:10

Hi,

I am transmit & receive data through eeprom(24c04en) using stm32f1. 

But there is a problem to receive data only 15 value I will receive after that 0xff data come.

I want to transmit and receive 40 data through eeprom.

Please suggest me how to get more 15 value and how to i config so i get the data.

I also attaching datasheet of eeprom 24c04en.

Thank You and Regards

 Vikas 

[S.Ma]

Posted on February 18, 2017 at 16:09

This eeprom has 512 bytes with 8 bit subaddres, the extra address bit are replacing the a0 a1 a2 slave address selectors. The page is 16 bytes. You can read as many bytes as you want in autoincrement. Writing is different and requires attention. You can write up to 16 bytes one shot. Not anywhere. If you want to write 16 bytes from 0x08 to 0x17, you must first write 0x08 to 0x0f, wait for write time, then write 0x10 to 0x17 and wait for write completion. Bigger eeprom have 16 bit sub address and use bigger pages with smaller write time. 24c128 for example.

[Vikas Agrawal]

Posted on February 20, 2017 at 06:08

could you give me example how to use a0,a1,a2 because right now i given ground to all a0,a1,a2 and read 16Byte data.

we don't have oscillscope so how i check wait for write time.

[Seb]

Posted on February 20, 2017 at 08:23

Have a look at this shared source code

https://community.st.com/0D50X00009XkW1qSAF