Campbell TX325, Руководство по эксплуатации продукта

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Table B-20: Encoding of NAN
Character 1 = I Character 2 = ? Character 3 = ~
Sign Exponent Mantissa Mantissa Mantissa
p 1 0 0 b16 b15 b14 b13 p 1 b12 b11 b10 b9 b8 b7 p 1 b6 b5 b4 b3 b2 b1
0 1 0 0 1 0 0 1 0 0 1 1 1 1 1 1 0 0 1 1 1 1 1 0
B.2.2 Pseudobinary
Pseudobinary or 18-bit integer data format is used to transmit a signed or unsigned integer. The
18 bits are encoded across 3 bytes. When signed, the value is encoded using a two-complement
representation. As an integer cannot directly represent a fractional number, measurements are
often scaled before storing to the GOES data table. For example, a water-level surface elevation
of 123.45 ft can be multiplied by 100 to get an integer of 12345. This integer is stored for
transmission with the encoding shown in
Table B-21 (p. 38).
Table B-21: Example encoding of water level surface elevation value of 12345
Character 1 = C Character 2 = @ Character 3 = y
p 1 b18 b17 b16 b15 b14 b13 p 1 b12 b11 b10 b9 b8 b7 p 1 b6 b5 b4 b3 b2 b1
0 1 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0 1 1 1 1 0 0 1
B.2.3 Additional pseudobinary representations
Other pseudobinary representations, such as 6, 12, and 24 bit integers, can be formed and
transmitted using CRBasic.
B.3 Transmission durations
Table B-22 (p. 39) provides the transmission durations, calculated from the number of bytes in a
message. Table B-23 (p. 39) provides the maximum data bytes for an assigned time slot duration.
TX325 Satellite Transmitter for GOES V2 38