HN29W25611T Datasheet, PDF (37/42 Pages) Hitachi Semiconductor – 256M AND type Flash Memory More than 16,057-sector (271,299,072-bit)

HN29W25611T-50H
Unusable Sector
Initially, the HN29W25611T includes unusable sectors. The unusable sectors must be distinguished from the
usable sectors by the system as follows.
1. Check the partial invalid sectors in the devices on the system. The usable sectors were programmed the
following data. Refer to the flowchart “Indication of unusable sectors”.
Initial Data of Usable Sectors
Column address 0H to 81FH 820H
Data
FFH
1CH
821H
71H
822H
C7H
823H
1CH
824H
71H
825H
C7H
826H to 83FH
FFH
2. Do not erase and program to the partial invalid sectors by the system.
START
Sector number = 0
Sector number =
Sector number + 1
Bad sector*^{2 No}
Read data
Column address = 820H to 825H
Check data*¹
Yes
No
Sector number = 16,383
Yes
END
Notes: 1. Refer to table "Initial data of usable sectors".
2. Bad sectors are installed in system.
Indication of Unusable Sectors
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