LBC-4000 L-Band Up/Down Converter System
Revision 6
Serial Interface Operation
8–5
MN-LBC-4000
8.2.1.3
Address Delimiter
This is the forward slash character ‘/’ (ASCII code 47).
8.2.1.4
Instruction Code
Upper and lower case alphabetic characters may be used (A-Z, and a-z).
This three-character alphabetic string, whenever possible, references the subject command or query. This aids in the readability of the
message, should it be displayed in its raw ASCII form.
8.2.1.5
Instruction Code Qualifier
The Instruction Code Qualifier is the underscore ‘_’ (ASCII code 95). This single character further qualifies the preceding instruction code.
The Instruction Code Qualifier obeys these rules:
1. From
Controller-to-Target
, the underscore ‘_’ plus additional parameter(s) comprise the assignment operator. This combination
defines the
command
configuration parameters that are issued to the Target.
For example, the Controller-to-Target command “<0001/MUT_A_ON{cr}” means ‘turn ON the mute function of Converter A’.
2. The ‘_’ underscore, when submitted Controller-to-Target without parameters, functions as a
query
. Submitted in this format, the
Controller directs the Target to report the current configured value for that parameter (Instruction Code).
For example, the Controller-to-Target query “<0001/MUT_A_{cr}” means ‘return the current state of the mute function of Converter
A’.
3. From
Target-to-Controller
, if the instruction sent from Controller-to-Target is successful, the Target responds by echoing that
same instruction to the Controller.
8.2.1.5.1
Error Response
If a Target cannot execute a Command or detects a protocol violation, the Controller generates an error response. For example:
>0001?RED ER Error Message{cr}{lf}
Note that:
•
The "/" address delimiter changes in the response to a "?".
•
The Instruction Code is echoed, followed by two unique characters provided for analysis. This example uses “ER”.
•
A text string explaining the error follows.
