YSI IQ S ENSOR N ET Field bus linking - Manual (Page 32)

Encoded data for field bus communication IQ S ENSOR N ET Field bus linking
30 ba76148e01 06/2013
5 Encoded data for field bus
communication
5.1 Data formats of the sensor datablock
Measured values
(Float 32)
The data for the main and secondary measured values are transmitted
in the IEE-754 standard 32-bit floating point format.
* MSB = Most significant bit, LSB = Least significant bit
If not all of the bits of the exponent are 0, the value is calculated accord-
ing to:
If all of the bits of the exponent are 0, the value is calculated according
to:
A value is 0 if all the bits of both the exponent as well as the mantissa
are 0.
Address Bit representation
Offset 0h bits
31-24 S = sign (bit 31)
E = exponent
(bits 30-23)
M = mantissa (bits 22-0)
Offset 1h bits
23-16
Offset 2h bits 15-8
Offset 3h bits 7-0
Evaluation Meaning
Measured value 0 Check the measured value status
Measured value
status <> 1 The measured value is invalid (error)
MSB* LSB*
S E E E E E E E
E M M M M M M M
M M M M M M M M
M M M M M M M M
) 2 ... 2 2 2 1 ( 2 1 23
0
3
20
2
21
1
22
127 − − − − − ⋅ + + ⋅ + ⋅ + ⋅ + ⋅ ⋅ − =
b b b b
E S M M M M V
) 2 ... 2 2 2 ( 2 1 23
0
3
20
2
21
1
22
126 − − − − − ⋅ + + ⋅ + ⋅ + ⋅ ⋅ ⋅ − =
b b b b
S M M M M V