Eccel Technology Ltd BIORADRDR0200 Manuel D’Utilisation
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4.2.2 Read Block (0x02)
Table 4.2
The ‘Read Block’ command takes as arguments the first block address to read (Block Address), the number of blocks
to read (Read Length), the byte offset in the data buffer (Data Buffer Offset), the Authentication Key Number and
(optionally) the Authentication Key. If the Authentication Key is set-up, the command first tries to authenticate the
sector which contains the first buffer. If authentication fails, the ‘Result Register’ is updated with the appropriate
error value and command execution finishes. After a successful authentication, the first block is read and stored in
the data buffer. The command continues to read following blocks if the Read Length is higher than 1. If the next
blocks fall into another tag memory sector this sector is authenticated using the same key. If everything goes well all
block bytes are copied to the Data Buffer starting from Data Buffer Offset and the Result Register is updated with the
‘No Error’ value. If the RFID Module is unable to read the block, an error value is stored in the Result Register.
to read (Read Length), the byte offset in the data buffer (Data Buffer Offset), the Authentication Key Number and
(optionally) the Authentication Key. If the Authentication Key is set-up, the command first tries to authenticate the
sector which contains the first buffer. If authentication fails, the ‘Result Register’ is updated with the appropriate
error value and command execution finishes. After a successful authentication, the first block is read and stored in
the data buffer. The command continues to read following blocks if the Read Length is higher than 1. If the next
blocks fall into another tag memory sector this sector is authenticated using the same key. If everything goes well all
block bytes are copied to the Data Buffer starting from Data Buffer Offset and the Result Register is updated with the
‘No Error’ value. If the RFID Module is unable to read the block, an error value is stored in the Result Register.
Command Number
Command Name
Valid Tag Types
Argument Offset [bytes]
0x00
0x01
0x02
0x03
0x04
Argument Name
Block Address
Read Length
Data Buffer Offset
Authentication Key
Number
Authentication Key
Argument Size [bytes]
0x01
0x01
0x01
0x01
0x06
Argument Description
Address of the first
block in the memory
that is to be read.
Number of blocks to
read. Value has to be
larger than 0.
Buffer offset in bytes of
where the data from
the tag is to be stored.
The total read size and
The total read size and
the offset must not
exceed the data buffer
length (number of
bytes).
The 6 least significant
bits define the
Authentication Key
Number from 0 to 39
that is to be used to
decrypt the data read.
If the most significant
bit (bit 7) is set, then
the key will be used as
key B. If bit 7 is zero it
key B. If bit 7 is zero it
will be used as key A. If
bit 6 is set, then the
key will be taken from
the following argument
list (next 6 bytes).
Optional parameter
used when bit 6 in
Authentication Key
Number argument is
set. This Key will be
used as Key B if bit 7 in
Authentication Key
Number is set or as Key
A if bit 7 is not set. The
byte order is the least
significant byte first.
0x02
Read Block
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