User guide

VEGACOM 557 Profibus DP 29
Data image in VEGACOM 557
Enquiry of measured value from the DP Master with control command 0xCC to DISBUS
In the 2 Byte output section of the VEGACOM 557 DP-Gateway , the DP Master enquir es with
the control command 0xCC and a block no. 1 … 32, one block with eight measured values
each fr om the DP-Gateway .
DP-Master: Control command: 0xCC
Block no.: 0x01...0x20
2 Byte
output section
Byte 1 Byte 2
control
command
Block no.
Enquiry of measured value from Profibus-Master
Image of measured value on Profibus DP with control command 0xCC on DISBUS
VEGACOM 557 answers with the block no. (0 … 31) decremented by the value 1
Answer of VEGACOM 557 to the enquiry of measured value from the Profibus-Master (here enquired block
no. = 3)
Example:
If the enquired measured value is the PC/DCS value no. 3
of VEGAMET no. 2, the value 0x23 (hex) is delivered in the
index byte.
Note:
The index delivered via the DISBUS on enquiry of measured value, is structured as follows:
Structure of the index byte on enquiry of measured value via DISBUS
Example:
Enquiry telegram to VEGACOM 557 (2 Byte):
Block no. 3 is enquired
Answering telegram of VEGACOM 557 (50Byte):
control word PC/DCS value no. 1, VEGAMET no. 1 PC/DCS value-no. 2, VEGAMET no. 1
0xYY = Index-Byte
0xHH = High-Byte measured value
0xLL = Low-Byte measured value