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Displaying and maintaining the NAND flash memory
The physical space of the NAND flash memory is divided into multiple blocks, each of which is
subdivided into multiple pages. The NAND flash memory is erased on a block basis and read on a page
basis; the memory spaces are allocated on a page basis.
Displaying and repairing bad blocks
Bad block ratio varies with products of different vendors. Bad blocks cannot be used to store data, and
the system has to skip the bad blocks when it allocates storage spaces to files. You can get the locations
of bad blocks and repair them at the command line interface.
Follow these steps to display and repair bad blocks:
To do…
Use the command…
Remarks
Display the number and location
of bad blocks in the NAND flash
memory
display nandflash badblock-location
[
|
{
begin
|
exclude
|
include
}
regular-expression
]
Required
Available in any view
Repair bad blocks
fixdisk
device
Required
Available in user view
Checking files
After files are written to the NAND flash memory, use the following commands together to check the
content of these files.
Follow these steps to check files:
To do…
Use the command…
Remarks
Display the space distribution of
the specified file in the NAND
flash memory
display nandflash file-location
filename
[
|
{
begin
|
exclude
|
include
}
regular-expression
]
Display data on the specified
physical page
display nandflash page-data
page-value
[
|
{
begin
|
exclude
|
include
}
regular-expression
]
Available in any view
Performing batch operations
A batch file consists of a set of executable commands. Executing a batch file is the same as executing the
commands in the batch file one by one.
You can edit a batch file on your PC, and then download or upload it to the device. If the extension of
the file is not
.bat
, use the
rename
command to change it to
.bat
.
Follow these steps below to execute a batch file:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Execute a batch file
execute
filename
Required
