
15 Ethernet interface
Syntax of a message unit
A message unit (for example: :REAR:SETUP 1) is made of several fields:
- Heading:
For the command messages (for example: :REAR:SETUP 1) or for the interrogation messages (for
example: :REAR ?), it is made of a character chain (simple heading) or of several chains separated with ":" (composed heading).
A chain includes from 1 to 12 alphanumerical characters or the "_" character (code ASCII 95 in decimal). Advisable chain length: 4 characters.
A heading chain always begins with an alphabetic character. It may be preceded by ":" (composed heading) or end with an interrogation point "?" (interrogation message).
An interrogation message must always be followed by the termination sequence.
One or several ASCII characters (0 to 32, in decimal except 10 and 13).
-One or several pieces of data:
(for example: :SPEED 1,MM_S), alphanumerical, numerical or made of any characters or binary bytes.
-Data separator:
a comma "," possibly followed and/or preceded by one or several "filling" characters in ASCII code (0 to 32, in decimal except 10 and 13).
Data:
There are several types of pieces of data:
-Alphanumerical data:
1 to
The chain must begin with an alphabetical character. For example, for a
-Decimal digital data:
made of a mantissa and possibly of an exponent, and figured as a succession of
- Text:
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