Sutron Xpert2, Руководство по эксплуатации и обслуживанию

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Finally, we add 64 to each piece and convert to ASCII (since the second piece is 63 we leave it
alone):
124, 63, 71 = ASCII "|?G"
Example 4 . Decoding the 3 byte string "@SW":
This is just like encoding except we follow the steps backward.
First we convert all the characters to ASCII decimal codes:
ASCII "@SW" = 64, 83, 87
Now we subtract 64 from each piece and convert to 6-bit binary:
0, 19, 23 = 000000 010011 010111
Finally, we combine all the bits to form one 18-bit two’s complement number and convert to
base 10:
000000010011010111 = 1239
SHEF and SHEFFIX
“SHEF” format conforms to NESDIS Standard Decimal format specifications. The format is
ASCII and readable by persons without the aid of a computer. Sensor data consists of label, age
of the data in minutes, the data interval in minutes, and data values listed most recent first (left in
example diagram). The label in the transmission comes from the Label property of the associated
telemetry setup block.
This message has three measurements, each with two readings, and battery voltage appended:
:HG 0 #15 10.20 10.15 :PC 0 #15 50 49 :TA 0 #15 -22.1 -22.0 :VB 0 12.2
| | | | | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | +- VB Reading
| | | | | | | | | | | | | | | | + -- Offset time
| | | | | | | | | | | | | | | +------ Sensor Name, VB
| | | | | | | | | | | | | | +------------- TA #2
| | | | | | | | | | | | | +------------------- TA #1
| | | | | | | | | | | | +---------------------- Interval
| | | | | | | | | | | +------------------------- Offset time
| | | | | | | | | | +---------------------------- Sensor Name, TA
| | | | | | | | | +-------------------------------- PC #2
| | | | | | | | +----------------------------------- PC #1
| | | | | | | +-------------------------------------- Interval
| | | | | | +----------------------------------------- Offset time
| | | | | +-------------------------------------------- Sensor Name, PC
| | | | +--------------------------------------------------- HG #2
| | | +--------------------------------------------------------- HG #1
| | +------------------------------------------------------------ Interval
| +--------------------------------------------------------------- Offset time
+------------------------------------------------------------------ Sensor Name, HG
“SHEF Fixed” is a special version of the SHEF format where numbers are fixed to seven
character:
:HG 0 #15 -12345. 12345.1 :PC 0 #15 12345.1 1234.11