User's Manual

Table Of Contents
Product Manual - RFID Reader LF60C SoliD 65
Chapter 7
Operation
7.4.2 SECS-I implementation
This message set describes the communication between a SECS-I reader and a
host. The host and the transponder reader communicate via an RS232 interface
(SECS-I).
Character structure Data is transmitted or received in a serial bit stream of 10 bits per character at
one of the specified data rates. The standard character has one start bit (0), 8
data bits and one stop bit (1). All bit transmissions are of the same duration.
SECS-I performs no parity or other verification of the individual bytes.
Block transfer
protocol
The gateway uses an interpretation of SECS-I by a serial transport layer. The
following are some points to note about this implementation.
Master-Slave The host connects to the reader. If there is a conflict, the host "gives in" (i.e.
receives before sending).
In the course of communication, the reader takes on the role of the master and
the host takes on the role of the slave.
Control characters The four standard handshake codes used in the block transfer protocol are
displayed in the table below.
<ENQ> 0x05 Request to send
<EOT> 0x04 Empfangsbereit
<ACK> 0x06 Korrekter Empfang
<NAK> 0x15 Fehlerhafter Empfang