VEGA VEGACOM 557 Profibus DP - Manual (Page 42)

42 VEGACOM 557 Profibus DP
Measured value image LOGBUS in mode 6E6A
In this operating mode, the PC/DCS values can be read out individually in VEGACOM 557, i.e.
the Profibus-Master enquires a measured value and the VEGACOM 557 delivers this meas-
ured value.
Control command 0xCD (LOGBUS)
When enquiring with this control command, VEGACOM 557 answers with an individual PC/
DCS value. The enquiry telegram, written by the Profibus-Master into the 6 Byte outputs is
structured as follows:
Byte1 Byte2 Byte3 Byte4 Byte5 Byte6
control
command
reserved
PC/DCS
number
reserved reserved reserved
0xCD 1...255 0xFF 0xFF 0xFF 0xFF
6 Byte
Format of the enquiry acc. to individual PC/DCS values
VEGACOM 557 writes the following answering telegram into the 6 Byte input of the Profibus-
Master:
6 Byte
Byte1 Byte2 Byte3 Byte4 Byte5 Byte6
Status Highword Lowword
Add. info
0xYY 1...255 0x00 0x00 0xHH 0xLL
PC/DCS
number
PC/DCS measured value
Format of the VEGACOM 557 answer
Status:
0x00 = valid measured value
0x01 = simulated m easured v alue ( only o n
VEGAMET 509 and 512)
0x80 = old measured value (probably con-
nection separated)
0xFE = no PC/DCS value available (not
configured)
0xFF = general error
Data image in VEGACOM 557
PC/DCS measured value
0xHH = High-Byte of the measured value
0xLL = Low-Byte of the measured value
Value section comprises max. +32.768 to
-32.767.