Eccel Technology Ltd BIORADRDR0200 Manuel D’Utilisation
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4.2.10 Read Value (0x0A)
Table 4.10
The Read Value command takes as arguments the address of the block where the value is stored (Block Address), the
offset of the Data Buffer where the value and read address will be stored (Data Buffer Offset), the Authentication
Key Number and (optionally) the Authentication Key. This command has the same functionality as the Read Block
command except it treats the block as a special Value type defined by the Mifare standard. It tries to parse the block
content to this 4-byte signed value and to read a-byte address stored in last four bytes of the block. If read was
successful, the value is stored in the Data Buffer at the pointed offset, with the address byte stored straight after the
value. The value is stored as a signed 32-bit integer, with least significant byte first, and the address is stored as an
unsigned 8-bit value.
offset of the Data Buffer where the value and read address will be stored (Data Buffer Offset), the Authentication
Key Number and (optionally) the Authentication Key. This command has the same functionality as the Read Block
command except it treats the block as a special Value type defined by the Mifare standard. It tries to parse the block
content to this 4-byte signed value and to read a-byte address stored in last four bytes of the block. If read was
successful, the value is stored in the Data Buffer at the pointed offset, with the address byte stored straight after the
value. The value is stored as a signed 32-bit integer, with least significant byte first, and the address is stored as an
unsigned 8-bit value.
Command Number
Command Name
Valid Tag Types
Argument Offset [bytes]
0x00
0x01
0x02
0x03
Argument Name
Block Address
Data Buffer Offset
Authentication Key
Number
Authentication Key
Argument Size [bytes]
0x01
0x01
0x01
0x06
Argument Description
The Block Address in
the memory from
which the value is to be
read. The block has to
be formatted as a value
type block before
reading.
Buffer offset in bytes
from where the data
read from the tag will
be stored. Total read
size and the offset
cannot exceed the data
buffer length.
The 6 least significant
bits define the
Authentication Key
from 0 to 39 that is to
be used to read the
data. If the most
significant bit (bit 7) is
set, then the key will be
used as Key B. If bit 7
is zero, then 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).
This optional
parameter is only used
when bit 6 of the
immediately preceding
Authentication Key
Number argument is
set. If used, this key
will be used as Key A if
bit 7 of the preceding
Authentication number
is set or as Key B if not
set. The byte order is
the least significant
byte first.
0x0A
Read Value
Mifare Classic