Comtech EF Data MBT-5003 - Manual (Page 81)

MBT-5003 L-Band Up/Down Converter System Revision 1
Appendix A MN-MBT5003
A–5
A.4.5 Instruction Code Qualifier
This single character further qualifies the preceding instruction code. Code Qualifiers obey the following rules:
1. From Controller-to-Target, the only permitted values are ‘=’ and ‘?’:
=
(ASCII code 61) The = code is used as the assignment operator, and is used to indicate that the parameter defined by the preceding byte
should be set to the value of the argument(s) which follow it.
For example, in a message from controller to target, MUT=1 would mean ‘enable the mute function’.
?
(ASCII code 63)
The ? code is used as the query operator, and is used to indicate that the target should return the current value of the
parameter defined by the preceding byte.
For example, in a message from controller to target, MUT? denotes ‘return the current state of the mute function.’
2. From Target-to-Controller, the only permitted values are ‘=’, ‘?’, ‘!’, ‘*’, ‘#’, and ‘$’:
=
(ASCII code 61)
The = code is used in two ways:
First, if the controller has sent a query code to a target (for example: MUT? meaning 'is mute enabled or disabled?'), the target
would respond with MUT=x, where x represents the state in question: 1 being enabled, and 0 being disabled.
Second, if the controller sends an instruction to set a parameter to a particular value, then, providing the value sent in the
argument is valid, the target will acknowledge the message by replying with MUT= (with no message arguments).
?
(ASCII code 63)
The ? code is only used as follows:
If the controller sends an instruction to set a parameter to a particular value, then, if the value sent in the argument is not valid,
the target will acknowledge the message by replying (for example) with MUT? (without message arguments). This indicates
that there was an error in the argument of the message sent by the controller.
!
(ASCII code 33)
The ! code is only used as follows:
If the controller sends an instruction code that the target does not recognize, the target will acknowledge the message by
echoing the invalid instruction, followed by the ! character with. Example: XYZ!
*
(ASCII code 42)
The * code is only used as follows:
If the controller sends an instruction to set a parameter to a particular value, and, if the value sent in the argument is valid,
however the target is in the wrong mode (for example, standby mode in redundancy configuration) that it will not permit that
particular parameter to be changed at that time, then the target will acknowledge the message by replying (for example)
with MUT* (without message arguments).