November 2016
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I
ndustrIal
C
ontrol
& C
omputIng
Time), EtherCAT, Sercos III and CC-Link IE
is generally the same as for group 1. For both
groups figure 2 compares the protocol hard-
ware/software layers of the Industrial Ethernet
standards mentioned above.
From the perspective of a manufacturer, bear-
ing all the various protocols in mind, it is of
particular importance to be able to cover all
these communication types with own net-
work products. Aside from the functional
view, commercial aspects are also import-
ant for success in the industrial automation
market. Looking to product cost parameters
like system simplicity, time to market, sup-
port, maintenance and many others, a prod-
uct change from one protocol to the other
should be possible with the identical product
hardware. In this context one also speaks of
the term multi-protocol device. Such devices
can be easily adjusted to a certain protocol by
just a simple replacement of the SW without
any hardware modification. Multi-protocol
support of an industrial automation prod-
uct can follow various strategies. Companies
have developed different solutions to run sev-
eral industrial automation protocols in their
products. All those solutions are generically
described in this article, a mixture between
them is possible of course. They have their
own pros and cons as described later. Some-
times the focus of the ideal solution can
change, especially when taking into account
different product phases and volumes in their
overall lifetime.
FPGAs are very flexible components which
allow a hardware function change while using
the same device. This is true in different sit-
uations when changing the function as such
(specification change), when modifying a cer-
tain part of it (customization or optimization)
or when applying a hardware fix (removing a
bug). They are also a good choice when cer-
tain system components are to be combined
in one device in order to save board space
and reduce the PCB complexity. Sometimes
boards have single gates or other low-com-
plexity logic (also known as glue-logic) which
can be completely integrated into the FPGA.
FPGAs are also flexible when the complexity
level of an implemented function has to be
changed. Pin-compatible FPGAs allow the
selection of the right number of usable gates.
With a bigger FPGA a more complex func-
Figure 1. Industry 4.0 - The fourth industrial revolution
