Specifications

D17XX OEM Integration v0.1
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www.cobham.com/domo
Domo Limited doing business as Cobham Surveillance
Z 20h-7Eh Status BYTE
PQR 20h-7Eh Data –Optional, variable length
; 3Bh Separator
X 80h-FFh Checksum
ETX 03h End byte
The checksum byte is a summation of all bytes in the packet, not including the start (02h) and end
(03h) bytes. The result is then modified by forcing bit 7 high to prevent ASCII control characters from
being sent. The resulting checksum is in the range of 80h - FFh.
The Status byte will indicate if the command performed OK, or indicate an error:
ASCII Meaning
1 All OK
E General error, Command could not be executed
Typically E will be returned if the message is formatted incorrectly (separators in wrong place) or if
commands are in upper case, or if commands do not match against the allowed list of commands, or
if the checksum is wrong.
Addresses in the range 0001 to 9998 are for general use. Address 0000 is reserved and 9999 is a
broadcast address. i.e. any device will reply to this address. Its reply will contain its own specific
address.
All data in the transmitter and receiver is stored as one of 5 data types, Double, Integer String, or
Hexadecimal integer. The data type dictates the contents of the data section of the reply.
 Double – Data always contains decimal point and 2 decimal places. Can have 1 to 4 digits before decimal.
 Integer –Data is 5-byte reply of integer value stuffed with preceding zeros. E.g. current preset reply 00006
= preset 6 is live.
 String – Data is variable length string excluding null terminator.
 Hex – Data should be interpreted as hexadecimal number of variable length.