Comtech EF Data KST-12025 - Manual (Page 112)

Remote Control Operation KST-12025 Ku-Band Satellite Terminal
A–2 Rev. 1
A.2 Message Structure
The ASCII character format used requires 11 bits/character:
•
1 Start bits
•
7 Information bits
•
1 Parity bit (odd, even)
•
2 Stop bits
Messages on the remote link fall into the categories of commands and responses.
Commands are messages which are transmitted to the RFT-1225, while responses are
messages returned by the RFT-1225 in response to a command.
The general message structure is as follows:
•
Start Character
•
Device Address
•
Command/Response
•
End of Message Character
A.2.1 Start Character
A single character precedes all messages transmitted on the remote link. This character
flags the start of a message. This character is:
•
“<” for commands
•
“>” for responses
A.2.2 Device Address
The device address is the address of the controller which is designated to receive a
transmitted command, or which is responding to a command.
Valid device addresses are 1 to 3 characters long, and in the range of 1 to 255. Address 0 is
reserved as a global address which simultaneously addresses all devices on a given
communications link. Devices do not acknowledge global commands.
Each RFT-1225 which is connected to a common remote communications link must be
assigned its own unique address. Addresses are software selectable at the modem, and must
be in the range of 1 to 255.