PNI SeaTRAX - Manual (Page 41)

PNI Sensor Corporation DOC#1018154 r02
SeaTRAX User Manual Page 36
7.2 Parameter Formats
Note: Floating-point based parameters conform to ANSI/IEEE Std 754-1985. Please refer to the
Standard for more information. PNI also recommends the user refer to the compi
ler’s instructions to
understand how the compiler implements floating-point format.
64 Bit Floating Point (Float64)
Below is the 64 bit float format in big Endian. In little Endian, the bytes are in
reverse order in 4 byte groups. (eg. big Endian: ABCD EFGH; little Endian:
DCBA HGFE).
Exponent S Mantissa
63 62 52 51 0
The value (v) is determined as (if and only if 0 < Exponent < 2047): v = (-1)S *
2(Exponent-1023) * 1.Mantissa
32 Bit Floating Point (Float32)
Shown below is the 32 bit float format in big Endian. In little Endian format, the 4
bytes are in reverse order (LSB first).
Exponent S Mantissa
3130 23 22 0
The value (v) is determined as (if and only if 0 < Exponent < 255): v = (-1)S *
2(Exponent-127) * 1.Mantissa
Signed 32 Bit Integer (SInt32)
SInt32-based parameters are signed 32 bit numbers (2’s compliment). Bit 31
represents the sign of the value (0=positive, 1=negative)
msb
31 24 23 16 15 8
lsb
7 0
Big Endian
lsb
7 0 15 8 23 16
msb
31 24
Little Endian