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Nor Flash

Naveenm685
New Contributor

We are using the Flash memory S25FL256SAGMFV01 in our system  for storing data logs , whenever we do sector erase we are facing the reset happening in the system,

 

kindly someone please provide help 

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5 Replies
AS_36
Moderator
Moderator

Hi,

Can you please provide some more details about your issue - 

  1. Please tell us the exact sequence of commands that you are following.
  2. Can you provide the schematic for the flash?
  3. Is sector erase the only operation you are performing on the flash or Is there any other operation also that you are performing?
  4. Apart from the failing sector erase operation, is there any other operation which is also failing?
  5. Are any of the other flash operations (read/program) working fine?
  6. How did you confirm that the device has been reset?
  7. Have you captured any SPI waveforms for the sector erase operation? If yes, can you provide that?
  8. How many flash devices are showing this behavior?

 

Regards.

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Naveenm685
New Contributor

Hi

Thanks for  the reply 

The commands used for the Erase is

  • sending write enable command (0x06)
  • sending sector erase command(0xdc)
  • sending address for erase
  • reading the flash status register until the erase is complete
  • disabling the write 

The other operations performed on the flash is like, write, read, sector erase,Bulk erase

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AS_36
Moderator
Moderator

Hi,

Thank you for providing the sequence of commands and list of operations.

  1. Can you please confirm that the address sent after 0xDC command is 4-byte address?
  2. Have you enabled any kind of sector protection scheme on your flash device?
  3. Have you tried to read the value of the Status Register after the sector erase operation failed? Are any of the error bits being set?
  4. Can you confirm whether the other flash operations (like write, read, sector erase, Bulk erase) passed or failed? If passed, how did you confirm that the operation was successful? Are you observing the SPI waveforms or are you reading the data from the flash and printing it to verify?
  5. How are you confirming that the device is being been reset after sector erase?
  6. It is important for us to look at the SPI waveforms to understand the issue better. Is it possible for you to provide the SPI waveforms for the failing sector erase operation and one of the flash program and read operations that passed?
  7. How many flash devices are showing this behavior?

 

Regards.

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Naveenm685
New Contributor

Thanks for the reply, we are sending four byte address

How to perform sector erase?

we need give sector number or sector address?

 

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AS_36
Moderator
Moderator

Hi,

>> we need give sector number or sector address?

You need to provide the sector address.

>> How to perform sector erase?

The correct sequence of commands is - 

  • Drive CS# LOW
  • Send WREN command (0x06)
  • Drive CS# HIGH
  •  
  • Drive CS# LOW
  • Send Sector Erase Command (0xDC)
  • Send 4 byte address
  • Drive CS# HIGH
  •  
  • Drive CS# LOW
  • Send Read Status Register command (0x05)
  • Read SR value
  • Drive CS# HIGH
  • Check WIP bit of SR. Continue polling the SR till the WIP bit becomes LOW indicating successful completion of the erase operation.
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