S-Bus Driver

Characteristics S-Bus

• Ease of handling

• Built into every PCD processor

• Fail-safe data transfer due to using CRC-16 error detection

• High transfer rate due to efficient binary protocol

• Connection monitoring and retransmit function

Supported telegram types in WinCC OA

Following telegram types are supported in the WinCC OA S-Bus driver:

• Read Flag

• Write Flag

• Read Register

• Write Register

• Read PCD Status

• Write System Program Version

• Read Text

• Write Text

• Input signals are only received on demand, i.e. "spontaneous" input mode is not supported.

• To increase performance, when polling data is grouped together to obtain higher transfer rate (see also MaxGap). Commands are not grouped together.

Redundancy

Redundant systems are supported by the S-Bus driver. In this case both drivers (active and passive) access the PLC at the same time. Commands are only sent from the active server, while data can be read from both drivers. The requirement is that both drivers can access the PLC at the same time.

Redundant connection to a PLC or redundant PLCs are not supported.