Comtech EF Data CRS-311 - Manual (Page 137)

CRS-311 1:1 Redundancy Switch Revision 7
Serial-based Remote Product Management MN/CRS311.IOM
6–7
2. 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, BKH? means, “what is the BacKup Holdoff time?” – the Target
responds with BKH=xx, where ‘xx’ represents the time in question.
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 BKH= (with no message arguments).
?
(ASCII code 63) If the Controller sends an instruction to set a parameter to a particular value, and the value sent is not valid, the Target then
acknowledges the message and responds with, for example, BKH? (with no message arguments). This indicates that there was an
error in the message sent by the Controller.
!
(ASCII code 33) If the Controller sends an instruction code that the Target does not recognize, the Target responds by echoing the invalid instruction,
followed by ! (Example: XYZ!)
*
(ASCII code 42) If the Controller sends the command to set a parameter to a particular value, and the value sent is valid BUT the router will not permit
that particular parameter to be changed at present, the Target acknowledges the message and responds with, for example, MLC* (with
message arguments).
#
(ASCII code 35) If the Controller sends a correctly formatted command, BUT the unit is not in Remote Mode, it does not allow reconfiguration and
responds, for example, with MLC#.
∼
(ASCII Code 126) If a message was sent via the Switch to an attached modem or ODU, the message was transmitted transparently through the Switch. In
the event of the other device not responding, the Switch would generate a response e.g. >0100/MGC
∼ indicating that it had finished
waiting for a response and was now ready for further COMs.
6.2.4.6 Optional Message Arguments
Arguments are not required for all messages. Arguments are ASCII codes for the characters ‘0’ to ‘9’ (ASCII codes 48 to 57); ‘A’ to ‘Z’
(ASCII codes 65 to 90); period ‘.’ (ASCII code 46); and comma ‘,’ (ASCII code 44).
6.2.4.7 End of Packet
• Controller‐to‐Target: This is the ‘Carriage Return’ ([CR]) character (ASCII code 13).