User's Manual

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3.3.5 Increment/decrement value (0x24)
This command should be used to increment or decrement a value stored in the tag memory. It takes as
arguments the block number where the value is stored, the key A or B parameter, the key number in key
storage, value (signed 32-bit LSB first) as 4 bytes to increment or decrement, and the increment/decrement
flag.
Command description
Argument
Size
Value
Description
Command ID
1
0x24
MF_
INCREMENT_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
Delta value
4
X
Signed 32
-
bit value (LSB first)
Increment/Decrement 1 X
0x00
–
Decrement by delta
value
0x01 – Increment by delta value
Response
description
ACK
1
0x00
Command ID
1
0x24
MF_
INCREMENT_VALUE
Example:
HOST=>READER: 0x24 – MF_INCREMENT_VALUE
0x02 – block number 2
0x0A – key A should be selected from key storage
0x00 – first key should be selected from key storage
0x00 0x00 0x00 0x01 – delta value
0x01 – increment flag
READER=>HOST: 0x00 – ACK byte
0x24 – related command code MF_INCREMENT_BLOCK
3.3.6 Transfer value (0x25)
This command should be used to transfer a value from a volatile register on the tag to the block being
addressed. It takes as arguments the block number where the value should be stored, the key A or B
parameter, the key number in key storage.
Command description
Argument
Size
Value
Description
Command ID
1
0x25
MF_
TRANSFER_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
0x25
MF_
TRANSFER_VALUE
Example: