User's Manual

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HOST=>READER: 0x25 – MF_TRANSFER_VALUE
0x02 – block number 2
0x0A – key A should be selected from key storage
0x00 – first key should be selected from key storage
READER=>HOST: 0x00 – ACK byte
0x25 – related command code MF_TRANSFER_BLOCK
3.3.7 Restore value (0x26)
This command should be used to restore a value to a volatile register on the tag from the block being
addressed. It takes as arguments the block number where the value is stored, the key A or B parameter,
key number in key storage.
Command description
Argument
Size
Value
Description
Command ID
1
0x26
MF_
RESTORE_VALUE
Block number
1
X
Key A/B parameter 1 X
0x0A
–
Key A should be selected from key storage
0x0B – Key B should be selected from key storage
Key number
1
0
-
4
Key number in key storage
Response
description
ACK
1
0x00
Command ID
1
0x26
MF_
RESTORE _VALUE
Example:
HOST=>READER: 0x26 – MF_RESTORE_VALUE
0x02 – block number 2
0x0A – key A should be selected from key storage
0x00 – first key should be selected from key storage
READER=>HOST: 0x00 – ACK byte
0x26 – related command code MF_RESTORE_BLOCK
3.3.8 Transfer-Restore value (0x27)
This command performs a Restore-Transfer command sequence on the tag. It takes as arguments the block
number to be decremented, the block number to be transferred to, the key A or B parameter, the key
number in key storage. This command has the same functionality as the read value command, except that
it can be used on a block which is corrupted – it tries to recover data from a corrupted block. The format
of a value-type block allows for some bits to be corrupted and it still be possible to read and recover the
proper value
Command description
Argument
Size
Value
Description
Command ID
1
0x27
MF_
TRANSFER_RESTORE_VALUE
Source block
number
1
X
Block number to be decremented
Destination block
number
1 X Block number to be transferred to