IC-Module for EtherNet/IP
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SSC Master Operating Mode
In this operating mode, output data is read from the SSC output
register area via the serial synchronous interface and written to a
shift register string. At the same time, data is read from the shift
register chain and written to the SSC input register area. This takes
place via a hardware shift register chain.
Illustration 6:
Hardware shift register chain, example with 4 inputs and outputs
The advantage of such an interface is the possibility of forwarding
input and output signals to the fieldbus without the need of
microprocessor controlled application circuitry. Switches, contacts,
relay coils or solenoid valves, for example, can therefore be
connected directly via EtherNet/IP without using a microprocessor.
The KUNBUS-IC with its clock clocks the output data into the input
register of the chain via the MOSI line, where it is shifted bit by bit
until the end. At the same time, the input data is shifted bit by bit via
the MISO line into the KUNBUS-IC with the same clock pulse. Prior
to each such shift procedure, the module sets the LOAD line to high.
This means that the data transferred in the previous cycle is output
by all output modules simultaneously on the output pins. The input
Components
