Specifications

ADT60/AET60 Reference Manual version 1.5 November 2005
7. PC-Reader Communication protocol
During normal operation, the BioCARDKey/BioSIMKey smart card reader acts as a slave with regards to the
communication between a computer and the device. The communication is carried out in the form of
successive command-response exchanges. The computer transmits a command to the reader and receives
a response from the reader after the command has been executed. A new command can be transmitted to
the BioCARDKey/BioSIMKey smart card reader only after the response to the previous command has been
received.
There are only two cases where the reader transmits data without having received a command from the
computer, namely, the Reset Message of the reader and the Card Status Message.
7.1 Command
7.1.1 Normal Command (Length < 255 bytes)
A command consists of four protocol bytes and a variable number of data bytes and has the following
structure:
Byte 1 2 3 4 ... N+3 (0<N<255) N+4
Header Instruction Data length = N Data Checksum
Header Always 01
H
to indicate the start of a command.
Instruction The instruction code of the command to be carried out by the BioCARDKey/BioSIMKey
Data Length Number of subsequent data bytes. (0 < N < 255)
Data Data contents of the command.
For a READ command, for example, the data bytes would specify the start address and the
number of bytes to be read. For a WRITE command, the data bytes would specify the start
address and the data to be written to the card.
The data bytes can represent values to be written to a card and/or command parameters
such as an address, a counter, etc.
Checksum The checksum is computed by XORing all command bytes including header, instruction,
data length and all data bytes.
The following example shows the structure of a command with instruction code = 91
H
and three data bytes
with the values 11
H
, 22
H
and 33
H
, respectively:
byte 1 2 3 4 5 6 7
01
H
91
H
03
H
11
H
22
H
33
H
93
H
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