bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
1
st
row
2nd
t
row
3rd row
4th row
253th row
254
th t
row
255
th
row
256
th
row
P1o
P1e
P1o
P1e
P1o
P1e
P1o
P1e
P2o
P2e
P2o
P2e
P4o
P4e
P16e
P16o
P16e
P16o
P32e
P32o
P32e
P32o
P2048e
P2048o
512 Bytes input
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
P1o
P1e
P1o
P1e
P1o
P1e
P1o
P1e
P2o
P2e
P2o
P2e
P4o
P4e
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
P8o
P8e
P16e
P16o
P16e
P16o
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
1st row
2nd row
3rd row
4th row
253th row
254th row
255th row
256th row
P1o
P1o
P1o
P1o
P2o
P2o
P4o
P16o
P16o
P32o
P32o
P2048o
51-bytes input
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
P1o
P1o
P1o
P1o
P2o
P2o
P4o
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
P8o
P16o
P16o
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
1
st
row
2nd
t
row
3rd row
4th row
123th row
124
th t
row
125
th
row
128
th
row
P1o
P1e
P1o
P1e
P1o
P1e
P1o
P1e
P2o
P2e
P2o
P2e
P4o
P4e
P16e
P16o
P16e
P16o
P32e
P32o
P32e
P32o
P1024e
P1024o
256 Bytes input
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
P1o
P1e
P1o
P1e
P1o
P1e
P1o
P1e
P2o
P2e
P2o
P2e
P4o
P4e
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
P8o
P8e
P16e
P16o
P16e
P16o
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
1st row
2nd row
3rd row
4th row
123th row
124th row
125th row
128th row
P1o
P1o
P1o
P1o
P2o
P2o
P4o
P16o
P16o
P32o
P32o
P1024o
256 byte input
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
P1o
P1o
P1o
P1o
P2o
P2o
P4o
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
P8o
P16o
P16o
GPMC
7.1.3.3.12.3.1.6 ECC Calculation Based on 16-Bit Word
ECC computation based on a 16-bit word is used for 16-bit wide NAND device interfacing. This ECC
computation is not supported when interfacing an 8-bit wide NAND device, and the
GPMC_ECC_CONFIG[7] ECC16B bit must be cleared to 0 when interfacing an 8-bit wide NAND device.
The parity computation based on 16-bit words affects the row and column parity mapping. The main
difference is that the odd and even parity bits P8o and P8e are computed on rows for an 8-bit based ECC
while there are computed on columns for a 16-bit based ECC.
and
Figure 7-35. 128 Word16 ECC Computation
Figure 7-36. 256 Word16 ECC Computation
314
Memory Subsystem
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated