TransCore SmartPass AI1611, Системное руководство

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SmartPass® Integrated Reader 2450 MHz (High Voltage) System Guide
Host Transmission
Synchronous communications between the reader and the host are initiated by the
host. The host begins a sequence by issuing a command; the reader will respond
accordingly.
The data inquiry protocol format is:
<CTRL-E>
The basic protocol format is:
<som><cmd>[<data>]<eom>
The ECP format is:
<som><seq><cmd>[<data>]<crc><eom>
where
<CTRL-E>
ASCII Control E (hex 5 digit). When in data inquiry mode,
each transmission of a CTRL-E by the host causes the
reader to transmit one tag ID.
<som>
Start-of-message (ASCII # character)
<seq>
Sequence number (ASCII hex digit) that represents an odd
number in the range 1–9,
A–F. The host should use odd sequence numbers in its
command, because the reader uses even sequence numbers
in its transmissions. This eliminates the possibility of a
synchronous host command and an asynchronous reader
transmission having the same sequence number.
Upon receiving a host command, the reader is expected to
echo the command's sequence number in its response.
Therefore, the host must update its sequence number upon
receipt of a valid reader message. If the sequence number is
not updated before transmission of the next command, the
reader will not service the new command; it will retransmit
its previous message. A command/message sequence is not
considered complete until the host updates its sequence
number.
<cmd>
Command code, a string that contains from 2 to 4 ASCII hex
characters
[<data>]
Optional data field, an ASCII string of up to 20 characters in
length. For example, the set date command is
21MM/DD/YY (command 21 followed by the data string
MM/DD/YY).
<crc>
CRC for the message
<eom>
End-of-message character (ASCII CR)
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