TransCore MPRX, Системное руководство

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MPRX
TransCore Proprietary 6–7
<som> Start-of-message (ASCII # character)
<seq>
Sequence number (ASCII hex digit) that represents an odd number in the
range 0–9, A–F (1, 3, 5, 7, 9, B, D, F). The host should use odd sequence
numbers in its command since the MPRX uses even sequence numbers in
its transmissions. This method eliminates the possibility of a synchronous
host command and an asynchronous reader transmission having the same
sequence number.
Upon receiving a host command in ECP, the MPRX replies using the
command’s sequence number in its response. Therefore, the host device
updates its sequence number upon receipt of a valid reader response.
If the sequence number is not updated before transmission of the next
command, the MPRX will not service the new command; it will retransmit its
previous message. A command/message sequence is not complete until
the host updates its sequence number.
<cmd>
Command code, a string that contains from two to four ASCII hex characters
[<data>] Optional data field, an ASCII string of as many as 20 characters in length. For
example, the store hardware configuration string command is
#696S...S
or command #696 Store Hardware Configuration String followed by the
data string S...S.]
<crc>
CRC value for the message
<eom> End-of-message character (ASCII CR)
Reader Command Response
The basic protocol format is
<som><resp><eom>
The ECP format is
<som><seq><resp><crc><eom>
where
<som>
Start-of-message (ASCII # character)
<seq>
Echo of sequence number received in host command message
<resp>
Response string. The MPRX returns
Done, Error,
or another ASCII string
depending on the host transmission. This string can be up to 72 characters
long.
<crc>
CRC value for the message
<eom> E
nd-of-message character (ASCII CR and LF)
Sample Messages