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5 data formats, Data formats -10 – YSI DIQ/S 182 XT-4-PR User Manual

Page 126

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PROFIBUS connection

System 182 XT-4

7 - 10

ba76027e01

02/2012

7.5.5

Data formats

Measured values

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 exponents are 0, the value is calculated
according to:

If all of the bits of the exponents are 0, the value is calculated according
to:

A value is 0 if all the bits of both the exponents as well as the mantissa
are 0.

Note
If the measured value is equal to 0, check the measured value status.
If the measured value status is not equal to 1, an error has occurred
and the measured value is invalid.

Sensor model

Status info

The data for the sensor model and status info are transmitted as INT16,
i.e. consisting of 2 bytes. The assignment is carried out in Motorola
format (the higher value byte first).

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

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

Address

Bit representation

Information

Offset 0h bits 15-8

High byte

Offset 1h bits 7-0

Low byte

MSB

LSB