VEGA POINTRAC 31 Profibus PA - Manual (Page 53)

53
11 Supplement
POINTRAC 31 • Profibus PA
43835-EN-131119
The status byte corresponds to profile 3.02 "Profibus PA Profile for Process Control Devices" coded.
The status "Measured value OK" is coded as 80 (hex) (Bit7 = 1, Bit6 … 0 = 0).
The measured value is transferred as a 32 bit floating point number in the IEEE-754 format.
Byte n Byte n+1
Bit
7
VZ
Exponent
Bit
6
2
Bit
5
2
Bit
4
2
Bit
3
2
Bit
2
2
Bit
1
2
Bit
0
2
Bit
7
2
Bit
6
2
Bit
5
2
Bit
4
2
Bit
3
2
Bit
2
2
Bit
1
2
Bit
0
2
Sign
Bit
Significant
7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 -7
Byte n+2 Byte n+3
Bit
7
2
Significant
Bit
6
2
Bit
5
2
Bit
4
2
Bit
3
2
Bit
2
2
Bit
1
2
Bit
0
2
Bit
7
2
Bit
6
2
Bit
5
2
Bit
4
2
Bit
3
2
Bit
2
2
Bit
1
2
Bit
0
2
Significant
-9 -10 -11 -12 -13 -14 -15 -16 -17 -18 -19 -20 -21 -22 -23 -8
Value = (-1) VZ 2 (Exponent - 127) (1 + Significant)
Fig. 21: Data format of the measured value
Coding of the status byte associated with the PA output value
You can find further information for the coding of the status byte in the Device Description 3.02 on
www.profibus.com.
Status code Description according to
Profibus standard
Fault description
0 x 24 bad (F) Failure
0 x 3C bad (C) Function Check
0 x 78 uncertain (S) Out of Spec
0 x A4 good (M) Maintenance required
0 x A8 good (M) Maintenance demanded
0 x 00 good (G) Good
Mapping - User error codes
Priority Description according to
Profibus standard
User Error Codes NE-107 status
31 Hardware Failure 40, 41 FAILURE
30 Memory Failure 34, 35, 36, 37 FAILURE
29 Software Failure 80 FAILURE
28 Parameterization corrupt 72 FAILURE
27 Undefined 27 - -
26 Undefined 26 - -
25 Parameterization Error 16, 17, 25, 52, 53, 57, 66,
117, 120
FAILURE
24 Conflict in MGC 121, 122, 141 FAILURE
23 Communication Error in
MGC
8 FAILURE
22 MGC-Slave reports Error 38 FAILURE
21 Undefined 21 - -
20 Undefined 20 - -