DCT Antares SB, User Manual

Page: 102 / 238

4.17. SERIAL PORT DEVICES
Having the unit to work on MDT PAD mode so that the serial port can
Example
exchange binary data with the IP-type Destination
04
. The attached de-
vice uses the byte
03
to signal the end of a binary message.
For this example let’s use the following PAD criteria:
•
PAD character 1: 03 (not included on message)
•
PAD character 2: FA
•
PAD size: 50
•
PAD timeout: 10 seconds.
Let us include the PAD characters on the message, and use as escape char
the
1B hex
value. Now we use the
MT
message to drive the unit to PAD
mode passing the criteria we just created:
>
SMTP010050T
\
03
\
FA
\
1B
\
FF;ROUTE=4
<
After responding the command, the serial port is driven into PAD mode.
For now on, binary data can be exchanged.
Let’s see how data is transformed in order to be delivered to the remote
destination and vice versa.
Supposing the external device sends the following data:
Note: Non-printable data is shown between [ ] symbols in hex value
[02]Test message...[03]
The Antares SB
TM
after receiving the
03
byte will send to Destination
04
the following
TX
message:
>
RTX
\
02Test message...
\
03
<
Now, if the device sends:
[02][10][1F][AB][AB][3B][12]ABCD[08][09][FC][03]
The unit will send the
TX
message:
>
RTX
\
02
\
10
\
1F
\
AB
\
AB
\
3B
\
12ABCD
\
b
\
t
\
FC
\
03
<
Notice that for bytes 8 and 9 the special characters listed on the
TX
message
were used.
The inverse process works in the same way. When the remote host sends to
Antares SB
TM
a
TX
message it can contain any byte-like character by means
of escape sequences.
If the host would like to send the sequence:
[02][07][08][FC][AA]xyz[F1]
to the device attached on the serial port, then it has to send the follow-
ing
TX
message to the Antares:
>
STX
\
02
\
a
\
b
\
FC
\
AAxyz
\
F1
<
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