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Nor Flash

Anonymous
Not applicable

Hi,

I am attempting to erase, write and read to/from the first 64K sector of FLASH (sector address 0x0). I can do this successfully on subsequent sectors without issue.

I have confirmed that the BP bits in the status register are all set to 0, and that reading the DYB access register (using 0xe0 command and address 0x0) results in 0xff, indicating the sector is not protected from erase/write.

I think it is the first 32bytes in the sector that are causing the issue but I don't know why

Thank you

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1 Solution
Anonymous
Not applicable

Hi Krishna,

I have discovered that the read function that I am using is limited and cannot read the first part of the first sector. Please close this query

Many thanks for your support

View solution in original post

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6 Replies
Anonymous
Not applicable

Hello Sandy,

Please tell us the full part number you are using.

Also please read status register and configuration registers and let us know the values.

Thanks,

Krishna.

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Anonymous
Not applicable

HI Krishna,

As read from top of device the type number is FL256SAIH20 with the string (data code?) "04288411 A" below.

The status register and configuration register contents immediately prior to erase are 0x00 and 0x00. Prior to write/read the status register remains at 0x00 and configuration register is 0x02 (QUAD mode selected)

Thanks

Sandy

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Anonymous
Not applicable

Hello Sandy,

Can you try the command PPBRD ( E2h) and let us know what is the value you are getting.

Thanks,

Krishna.

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Anonymous
Not applicable

Hi Krishna,

The value read using OxE2 comand  = 0x00. This is for the first and subsequenct sectors

Thanks

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Anonymous
Not applicable

Hello Sandy,

That means the sector is protected.

Please refer section 7.5.10 in datasheet.The sector might have been protected using Advanced sector protection.

Also read ASPR register ( 2Bh)  (refer section 7.5.7)  to know whether it is in Password protected or persistent protected.

Thanks,

Krishna.

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Anonymous
Not applicable

Hi Krishna,

I have discovered that the read function that I am using is limited and cannot read the first part of the first sector. Please close this query

Many thanks for your support

View solution in original post

0 Likes