8 



c 



I 



•H 

 -P 

 •H 



Function 



Control character (RS); record separator 

 identifies start of platform replies 



Sensor platform address identifier 



? or space; shows whether address was correct 

 or not 



Date-time of reception; # day of year, hour, 

 minute, and second 



Platform data; without final EOT characters 



Control characters (RS); separates platform 



replies within bulletin 1 



Next reply follows, as above, from "Sensor Platform address identifier." 



Bulletins are segmented into uniform length blocks for transmission. 

 Bulletins are generally less than 10 full blocks; the only exception 

 being when a report beginning in the ninth block spans one or more 

 blocks. Each block is formatted as follows: 



Control character; start of transmission 



block (SOH or STX) 1 



Message characters 190 



Control character; end of transmission 



block (ETB or ETX) 1 



Block error control character; LRC (or CRC-16) 1 (or 2) 



NOTES : 



(1) Start of transmission block character is SOH for 

 initial block, STX for subsequent blocks. 



(2) End of transmission block character is ETB for 

 initial blocks, ETX for final block. 



(3) Final block may have 1 to 190 message characters 



(4) Block error control character: if longitudinal 

 redundancy check (LRC), it is composed to the MOD-2 

 sum of corresponding character bit positions of all 

 characters following the start of transmission block 

 character, except that its parity bit is odd parity; 

 if cyclic redundancy check (CRC-16), it is the 16-bit 

 remainder after division of the message characters 

 (following the start of transmission block character) 

 by the polynominal x^^ + x^^ + x^ + 1. 



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