The value in the reply is the value actually recognized by the device. For instance, if the
requested value was out of range, the replied (and internally used) value is limited to the
applicable minimum or maximum.
To read a parameter from the LFTXRX, instead of a new parameter value a question mark is
sent:
name=?
The device replies the actual value in a complete message:
name=value
A complete list of the parameter the sat-nms LFTXRX knows is shown later in this document in
chapter
Parameter list
. Below, some common rules applying to the remote control message
syntax are summarized.
Parameter names always are of lower case letters, most of them are four characters long.
Non-numeric parameter values always are written in upper case.
Numeric (floating point) values may be specified with an arbitrary precision, however the
device will reply only a fixed number of places. The LFTXRX recognizes a decimal point ('.'),
numbers must not contain any commas.
There must not be any white space in front or after the '=' in a message.
If the command/query is not of the form name=value or name=? , the LFTXRX replies the
message ?SYNTAX .
If the message syntax is OK, but contains an unknown parameter name is used, the reply is
?UNKNOWN
Numeric parameters are cut to the limits defined for this particular parameter.
Misspelled choice values cause the LFTXRX to set the first value of the choice list.
Assigning a value to a read-only parameter will cause no fault, however the LFTXRX will
overwrite this parameter immediately or some seconds later with the actual value.
4.2 The TCP/IP remote control interface
Controlling the sat-nms LFTXRX Optical Links through the network is done by means of HTTP
GET requests. Setting parameter values or querying readings or settings, all is done by
requesting HTTP documents from the unit. The message to the LFTXRX thereby is coded into the
URL as a CGI form parameter. The device replies a one line document of the MIME type
'text/plain'.
The document name for remote control is /rmt , hence (assuming the LFTXRX is listening to the
IP address 10.0.0.1), requesting a document with the URL
http://10.0.0.1/rmt?sver=?
will let the LFTXRX reply the software version in a one line text document:
sver=1.012 2007-12-01
This way all parameters may be queried or set, you may use your favourite web browser to try
out the remote control of the LFTXRX manually.
4.3 The RS232 remote control interface
(C) 2021, SatService GmbH
www.satnms.com
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