Balluff Inc BISS301J User Manual
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Communication between the BIS S-60_2 processor and the host system is via PROFIBUS-DP.
The PROFIBUS-DP system consists of the components:
– the bus master and
– the bus modules/slaves (here the BIS S-60_2 processor).
– the bus modules/slaves (here the BIS S-60_2 processor).
Important hints for use with PLC:
In some control systems the PROFIBUS-DP data area is not synchronously transmitted with the
updating of the input/output content. If more than 2 bytes of data are sent, a mechanism must
be used which guarantees that the data in the PLC and the data in the BIS S are always identi-
cal!
updating of the input/output content. If more than 2 bytes of data are sent, a mechanism must
be used which guarantees that the data in the PLC and the data in the BIS S are always identi-
cal!
1st alternative: Synchronous data transmission as a setting on the Master
In this method the bus Master ensures that all the data necessary for the respective Slave are
always sent contiguously. There is usually a special software function in the PLC which likewise
controls access between the PLC and bus Master so that data are always sent contiguously.
In this method the bus Master ensures that all the data necessary for the respective Slave are
always sent contiguously. There is usually a special software function in the PLC which likewise
controls access between the PLC and bus Master so that data are always sent contiguously.
2nd alternative: Set 2nd bit header
Data exchange between PLC and BIS is controlled by the so-called bit header. This is always
the first byte of the respective read/write head in the data buffer. This bit header exists both in
the input range (data from BIS to the PLC) and in the output range (data from the PLC to the
BIS). lIf this bit header is also sent as the last byte, a comparison of these two bytes can be
used to guarantee the consistency of the transmitted data.
Data exchange between PLC and BIS is controlled by the so-called bit header. This is always
the first byte of the respective read/write head in the data buffer. This bit header exists both in
the input range (data from BIS to the PLC) and in the output range (data from the PLC to the
BIS). lIf this bit header is also sent as the last byte, a comparison of these two bytes can be
used to guarantee the consistency of the transmitted data.
In this method the PLC cycle is unaffected nor is the bus access time changed. All that is
required is that a byte in the data buffer be used for the 2nd bit header instead of for user data.
required is that a byte in the data buffer be used for the 2nd bit header instead of for user data.
This 2nd alternative is the Balluff recommended setting (factory default).
PROFIBUS-DP
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BUS interface PROFIBUS-DP
S60_2-019_828318_0303-e mit CRC.p65
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Station Address
For the correct parametering of the bus master as per type, CD ROM, containing the unit’s
master data in the form of a GSD file is included with the BIS S-60_2 processor.
master data in the form of a GSD file is included with the BIS S-60_2 processor.
The Processor BIS S-60_2 is delivered with the station address 126. This has to be set indi-
vidually before using in a bus system. See information on 11.
vidually before using in a bus system. See information on 11.
An input buffer and an output buffer are used for the data exchange with the control system.
The size of these buffers has to be configured via the master.
The size of these buffers has to be configured via the master.
The possible settings are entered in the GSD file (and Type file). A minimum of 4 and a maxi-
mum of 128 bytes can be accommodated. However, it must be an even number.
mum of 128 bytes can be accommodated. However, it must be an even number.
Besides, in the case of the BIS S-60_2 processor, there are 6 further bytes (User-Parameter
Bytes) which have to be set while parametering. The significance of the 6 bytes for para-
metering is described starting from 22.
Bytes) which have to be set while parametering. The significance of the 6 bytes for para-
metering is described starting from 22.
The preset is stored in the GSD file.
Input/Output Buffer
Unit's Master Data
Parametering Bytes
User-Parameter Bytes
User-Parameter Bytes
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BUS interface PROFIBUS-DP