User's Manual

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Example:
HOST=>READER: 0x22 – MF_READ_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
0x22 – related command code MF_READ_BLOCK
0x00 0x00 0x00 0x01 – value
0x01 – address byte
5.3.4 Write value (0x23)
This command should be used to write a value to the tag. 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, a value (signed 32-bit LSB
first) as 4 bytes, and an address byte (unsigned 8-bit value).
Command description
Argument
Size
Value
Description
Command ID
1
0x23
MF_
WRITE_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
Value
4
X
Signed 32
-
bit value (LSB first)
Address
1
X
Address byte
Response
description
ACK
1
0x00
Command ID
1
0x23
MF_
WRITE_VALUE
Example:
HOST=>READER: 0x23 – MF_WRITE_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 – value
0x01 – address byte
READER=>HOST: 0x00 – ACK byte
0x23 – related command code MF_WRITE_BLOCK
5.3.5 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.