Toshiba H1 Series - Manual (Page 245)

TMP92CZ26A
92CZ26A-242
3.11.3 ECC Control
NAND Flash memory devices may inherently include error bits. It is therefore necessary to
implement the error correction processing using ECC (Error Correction Code).
Figure 3.11.4 shows a basic flowchart for ECC control.
Figure 3.11.4 Basic Flow of ECC Control
Write:
1. When data is written to the actual NAND Flash memory, the ECC generator in
the NDFC simultaneously generates ECC for the written data.
2. The ECC is written to the redundant area in the NAND Flash separately from
the valid data.
Read:
1. When data is read from the actual NAND Flash memory, the ECC generator in
the NDFC simultaneously generates ECC for the read data.
2. The ECC for the written data and the ECC for the read data are compared to
detect and correct error bits.
Valid data write to
NAND Flash
END
Data Write Data Read
Valid data write to
ECC generator
Write ECC to
NAND Flash
Valid data read from
NAND Flash
END
ECC read from
NAND Flash
ECC read
from ECC generator
ECC read from
ECC circuit
Is there error?
Yes
No
Valid data write to
ECC generator
Error correction
process