TMP92CZ26A

92CZ26A-242

3.11.3 ECC Control

NAND Flash memory device s may inherently include error bits. It is therefore necessary to
implement t he error correction processing using ECC (Error Correction Co de).
Figure 3.11.4 shows a basic flowchart for ECC control.
Figure 3.11.4 Basic Flo w of ECC Control
Write:
1. When data is written to the actual NAND Flash memory, the ECC generator in
the NDFC simultane ousl y ge nerates ECC for the written data.
2. The ECC is written to the redundant area in the NAND Fl ash 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
g
enerato
r
ECC read from
ECC circuit
Is there error? Yes
No
Valid data write to
ECC generator
Error correction
p
rocess