Comtech EF Data CRS-311 - Manual (Page 135)

CRS-311 1:1 Redundancy Switch Revision 7
Serial-based Remote Product Management MN/CRS311.IOM
6–5
Target-to-Controller (Response to Command or Query)
Start of Packet Target Address Address Delimiter Instruction Code Code Qualifier Optional Arguments End of Packet
>
ASCII code 62
(1 character) (4 characters)
/
ASCII code 47
(1 character) (3 characters)
= or ?
ASCII codes 61 or 63
(1 character) (n characters)
Carriage Return
ASCII code 13
(1 character)
Detailed description of the packet components follow.
6.2.4.1 Start of Packet
• Controller‐to‐Target: This is the character ‘<’ (ASCII code 60).
• Target‐to‐Controller: This is the character ‘>’ (ASCII code 62).
The ‘<’ and ‘>’ characters indicate the start of packet. They may not appear anywhere else within the body of the message.
6.2.4.2 Target Address
While up to 9,999 devices can be uniquely addressed, connection to the CRS‐311 imposes some basic limitations:
In EIA‐232 applications, the Switch address is fixed at 0000.
In EIA‐485 applications, the Switch may be set to an address of 1000, 3000, 5000 or 7000. This allows up to four Switches to be
connected on the same bus.
Remote commands and queries that can be sent to the modems via the Switch depend upon the modem protocol and the installed
options. Please consult the appropriate modem manual for further information. An external M&C application can monitor the
modems, transparently through the Switch, using virtual addressing:
• 0100 for the Traffic Modem, and
• 1100 for the Redundant Modem, which are added to the address of the Switch.