Comtech EF Data CRS-300 - Manual (Page 222)

CRS-300 1:10 Redundancy Switch MN/CRS300.IOM
Serial-based Remote Product Management Revision 19
7–6
There also are address restrictions for distant-end modems (being accessed by EDMAC) and Comtech transceivers, connected either
locally or at the distant-end of a link. See Appendix C. ADDRESSING SCHEME INFORMATION for detailed addressing information and
diagrams.
B
7.5.1.3 Address Delimiter
This is the “forward slash” character '/' (ASCII code 47).
7.5.1.4 Instruction Code
This is a three-character alphabetic sequence, which identifies the subject of the message. Wherever possible, the instruction codes have
been chosen to have some significance – e.g., TFQ for transmit frequency, RMD for receive modulation type, etc. This aids in the
readability of the message, should it be displayed in its raw ASCII form. Only upper case alphabetic characters may be used (A-Z, ASCII
codes 65 through 90).
7.5.1.5 Instruction Code Qualifier
This is a single character, which further qualifies the preceding instruction code. Instruction Code Qualifiers obey the following rules:
1) From Controller-to-Target, the only permitted values are:
Code Qualifier Description
=
(ASCII code 61)
‘=’ is used as the Assignment Operator (AO) 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, BKH=12 would mean 'set the BacK-up Hold-Off time to 12 seconds.'
?
(ASCII code 63)
‘?’ is used as the Query Operator (QO) and is used to indicate that the Target should return the current value of the parameters defined by the
preceding byte. For example, BKH? means 'what is the current value of BacK-up Hold-Off time?'
2) From Target-to-Controller, the only permitted values are:
Code Qualifier Description
=
(ASCII code 61)
The ‘=’ qualifier is used in two ways:
a. If the Controller sends a query to a Target (for example, BKH? means 'what is the current value of BacK-up Hold-Off time?), the Target
responds with BKH=xx (where xx represents the time, in seconds, in question).
b. If the Controller sends a valid command to set a parameter to a particular value, then the Target responds with BKH= (with no message
arguments).