W29N02GVSIAA Datasheet, PDF (38/79 Pages) Winbond – W29N02GV 2G-BIT 3.3V NAND FLASH MEMORY

W29N02GV
9.3 COPY BACK operation
Copy Back operations require two command sets. Issue a READ for COPY BACK (00h-35h)
command first, then the PROGRAM for COPY BACK (85h-10h) command. Copy back operations are
only supported within a same plane.
9.3.1 READ for COPY BACK (00h-35h)
The READ for COPY BACK command is used together with the PROGRAM for COPY BACK (85h-
10h) command. To start execution, READ for COPY BACK (00h) command is written to the Command
Register, followed by the five cycles of the source page address. To start the transfer of the selected
page data from the memory array to the Cache Register, write the 35h command to the Command
Register.
After execution of the READ for COPY BACK command sequence and RY/#BY returns to HIGH
marking the completion of the operation, the transferred data from the source page into the Cache
Register may be read out by toggling #RE. Data is output sequentially from the column address that
was originally specified with the READ for COPY BACK command. RANDOM DATA OUTPUT (05h-
E0h) commands can be issued multiple times without any limitation after READ for COPY BACK
command has been executed (see Figures 9-19 and 9-20).
At this point the device is in ready state to accept the PROGRAM for COPY BACK command.
9.3.2 PROGRAM for COPY BACK (85h-10h)
After the READ for COPY BACK command operation has been completed and RY/#BY goes HIGH,
the PROGRAM for COPY BACK command can be written to the Command Register. The command
results in the transfer of data from the Cache Register to the Data Register, then internal operations
start programming of the new destination page. The sequence would be, write 85h to the Command
Register, followed by the five cycle destination page address to the NAND array. Next write the 10h
command to the Command Register; this will signal the internal controller to automatically start to
program the data to new destination page. During this programming time, RY/#BY will LOW. The
READ STATUS command can be used instead of the RY/#BY signal to determine when the program
is complete. When Status Register Bit 6 (I/O6) equals to “1”, Status Register Bit 0 (I/O0) will indicate
if the operation was successful or not.
The RANDOM DATA INPUT (85h) command can be used during the PROGRAM for COPY BACK
command for modifying the original data. Once the data is copied into the Cache Register using the
READ for COPY BACK (00h-35h) command, follow by writing the RANDOM DATA INPUT (85h)
command, along with the address of the data to be changed. The data to be changed is placed on
the external data pins. This operation copies the data into the Cache Register. Once the 10h
command is written to the Command Register, the original data and the modified data are transferred
to the Data Register, and programming of the new page commences. The RANDOM DATA INPUT
command can be issued numerous times without limitation, as necessary before starting the
programming sequence with 10h command.
Since COPY BACK operations do not use external memory and the data of source page might include
a bit errors, a competent ECC scheme should be developed to check the data before programming
data to a new destination page.
Release Date: February 1^st, 2016
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– Revision B