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Appendix B: Output message format
The RX-D2 processes the incoming data by blocks of 64 bits. These blocks are called vectors.
The buoy also sends its data in 64 bit vectors and protects each vector by a BCH (63, 51) error
correcting code. The receiver uses this code to detect and correct possible errors in the vector.
The result, a checked and corrected vector, is sent through the serial port at a rate of 1.28 Hz.
Serial message format
The serial message consists of five groups of four characters separated by commas. The
message is terminated by a carriage return:
SSNN, VVVV, VVVV, VVVV, VVVV<CR>
Each character is the hexadecimal representation of four sequential bits.
SSNN and <CR> are added by the receiver.
VVVV,VVVV,VVVV,VVVV is the hexadecimal representation of the received and corrected
64 bit vector, grouped in four words of 16 bits each.
The meanings of each of the fields in the message are:
SS
= status (see below)
NN
= line number cyclically counting from “00” to “FF”
VVVV = first 16 bit word of received vector
VVVV = second 16 bit word of received vector
VVVV = third 16 bit word of received vector
VVVV = last 16 bit word of received vector
<CR>
= carriage return
The status bits can have the following values:
“00”
= receiver is locked, no errors (vector is OK)
“01”
= one or more errors in vector repaired, vector is now OK
“02”
= too many errors in vector detected, vector is NOT OK
“03”
= vector is all zeros or all ones, vector is NOT OK
“04”
= receiver is in synchronizing mode, vectors are unreliable.
Status code “04” can occur in combination with “00” to “03”. Therefore all error codes from
“00” up to “07” are possible.
Buoy vector layout
The buoy vector layout is dependent on the exact type and revision of the buoy. Refer to the
buoy’s documentation for more information.
Summary of Contents for 45100
Page 2: ...2 Check if mains supply matches with the specifications of the device...
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Page 36: ...36 E 2 Directional Antenna 25 45 MHz Figure E3 Directional quarter wave antenna...
