4 instruction code, 5 instruction code qualifier – Comtech EF Data MBT-5000 User Manual
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MBT-5000 L-Band Up/Down Converter System
MN-MBT5000
Serial-based Remote Product Management
Revision 4
7–6
7.2.2.4 Instruction Code
This is a three-character alphabetic sequence that identifies the message subject.
Wherever possible, the instruction codes have been chosen to have some significance – e.g., FRE for Operating FREquency, IPA for
Management IP Address, etc. This aids in the readability of the message, should it be displayed in its raw ASCII form.
Upper case and lower case alphabetic characters may be used (‘A’ to ‘Z’ and ‘a’ to ‘z’, ASCII codes 65-90 and 97-172).
7.2.2.5 Instruction Code Qualifier
This is a single character that further qualifies the preceding instruction code. Code Qualifiers obey the following rules:
From Controller-to-Target, the only permitted characters are:
Character
Definition
=
(ASCII code 61)
This character is used as the Assignment Operator (AO). It establishes that the Instruction Code that precedes it is to
be used as a command to assign or configure operation. The instruction set that follows serves to assign the Target’s
new parameter setting or operational value.
Example:
From Controller-to-Target,
MUT=1 means “enable the mute function.”
?
(ASCII code 63)
This character is used as the Query Operator (QO). It establishes that the Instruction Code that precedes it is to be used
as a query that returns the Target’s current configured parameter setting or operational value.
Example: From Controller-to-Target, MUT? means “what’s the current state of the MUTE function?”
From Target-to-Controller, the only permitted characters are:
Character
Definition
=
(ASCII code 61)
This character is used in two ways:
a. If the Controller sends a query to the Target – for example: MUT? meaning “what’s the current state of the MUTE function?”, the
Target would respond with MUT=x, where x represents the state in question: 1 being enabled, and 0 being disabled.
b. If the Controller sends an instruction to set a parameter to a particular value, and the value sent is valid, the Target acknowledges
the message and responds with MUT= (with no message arguments).