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AShet.2
Associate
September 23, 2020
Solved

I am using M24M01eeprom. I am not able to read memory locations above 64k.

  • September 23, 2020
  • 2 replies
  • 1000 views

I used 7bit device address as 0x51. considering A16 bit as 1 for above 64k memory locations.

I am able to write though. and I confirmed it by writing to above 64k memory locations and reading it by using 7bit device address as 0x50 and doing sequential read starting at 0xFFFF and continued reading further.

but if I use address as 0x51 and start reading at location 0x010000(mem address in 16bit will be 0x0000) then I am not getting the data.

This topic has been closed for replies.
Best answer by Pierre P.

Note:

issue found: other I2C device on same bus responding to 0xA2.

EEPROM Slave address changed to avaoid conflict.

Team EEPROM suPPort

2 replies

Pierre P.
ST Employee
September 23, 2020

Hello,

In read 0x10000, do you send the name opcodes (except R/W) during the Sequential Random Read command ?

What is the result when you do: " if I use address as 0x51 and start reading at location 0x010000(mem address in 16bit will be 0x0000) "

BR

Team EEPROM suPPort

AShet.2
AShet.2Author
Associate
September 24, 2020

Hi,

In read 0x10000, do you send the name opcodes (except R/W) during the Sequential Random Read command ?

Can you please elaborate what you mean by name opcodes?

I am doing sequential Random Read command according to below attached image

with E1, E2 pulled down.

it looks like: this according to image attached at the bottom

start|0xA2|ACK|0x00|ACK|0x00|ACK|start|0xA3|ACK|0x00|ACK|...

in image there is dev sel* can u tell me what that * means or where it is explained? I could not find what it means or where the note of it is attached.

What is the result when you do: " if I use address as 0x51 and start reading at location 0x010000(mem address in 16bit will be 0x0000) "

here I read all 0x00.

0693W000004GvWMQA0.jpg

Pierre P.
Pierre P.Best answer
ST Employee
September 29, 2020

Note:

issue found: other I2C device on same bus responding to 0xA2.

EEPROM Slave address changed to avaoid conflict.

Team EEPROM suPPort