Device operations
NAND01G-B2B, NAND02G-B2C
6.4
Copy back program
The copy back program operation is used to copy the data stored in one page and
reprogram it in another page.
The copy back program operation does not require external memory and so the operation is
faster and more efficient because the reading and loading cycles are not required. The
operation is particularly useful when a portion of a block is updated and the rest of the block
needs to be copied to the newly assigned block.
If the copy back program operation fails an error is signalled in the status register. However
as the standard external ECC cannot be used with the copy back program operation bit error
due to charge loss cannot be detected. For this reason it is recommended to limit the
number of copy back program operations on the same data and or to improve the
performance of the ECC.
The copy back program operation requires four steps:
1. The first step reads the source page. The operation copies all 1056 words/ 2112 bytes
from the page into the data buffer. It requires:
–
–
–
one bus write cycle to setup the command
4 or 5 bus write cycles to input the source page address (see Table 6 and Table 7)
one bus write cycle to issue the confirm command code
2. When the device returns to the ready state (Ready/Busy High), the next bus write cycle
of the command is given with the 4 or 5 bus cycles to input the target page address
(see Table 6 and Table 7). Refer to Table 11 for the addresses that must be the same
for the source and target pages
3. Then the confirm command is issued to start the P/E/R controller.
To see the data input cycle for modifying the source page and an example of the copy back
program operation refer to Figure 11.
A data input cycle to modify a portion or a multiple distant portion of the source page, is
shown in Figure 12.
Table 11. Copy back program x8 addresses
Density
Same address for source and target pages
1 Gbit
no constraint
A28
2 Gbits
Table 12. Copy back program x16 addresses
Density Same address for source and target pages
1 Gbit
no constraint
A27
2 Gbits
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NUMONYX [ NUMONYX B.V ]
