Access IS LSR118 - 7.6 MIFARE Create Value Block (Key A or B)

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7.6 MIFARE create value block (key A or key B)
Use this command to authenticate the specified MIFARE block against the MIFARE media’s internal
Key A or B and then create a value block in that block number. The value block is initialised to the
specified 32-bit initial value.
A value block is a normal block reserved for storing numeric data, for example, the number of times
data writes to the card. Change a value block back to a normal block using the MIFARE write block
(key A or key B) command on page 43.
You must load the MIFARE key using MIFARE load key (on page 40) before sending this command.
Note: This command is NOT applicable to MIFARE Ultralight cards and fails if executed on
Ultralight cards. Ultralight cards do not support value blocks.
7.6.1 MIFARE command bytes
MIFARE command bytes
Command header
Command code
Block number
Initial value
[0x00]
[0x0A]
Create value block (Key A)
Block number
32 bit initial value
(MSB first)
[0x1A]
Create value block (Key B)
[0x4A]
Authenticate and create value block (Key A)
[0x5A]
Authenticate and create value block (Key B)
[0x8A] or [0xCA]
RF select, authenticate and create value
block (Key A)
[0x9A] or [0xDA]
RF select, authenticate and create value
block (Key B)
7.6.2 MIFARE response bytes
MIFARE response bytes
Response header
Response code
Block number
Status bytes
[0x00]
Any one of the following
values
(Command code + 1)
[0x0B] or [0x1B]
[0x4B] or [0x5B]
[0x8B] or [0xCB]
[0x9B] or [0xDB]
Block number
[0x90][0x00]
Success
[0x69][Status Code]
Failure
Refer to page 55 for information on MIFARE failure status codes.