The KaraHoff based PLCSs
------------------------

There are by now several PLCs which are actually controlled by Raspberry PIs,
often in the variant of a Revolution Pi by Kunbus.

How to use the KaraHoff PLCs
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The Raspberrys run `KaraHoff <https://karabodevices.pages.xfel.eu/karahoff/>`_
and `EBPFCat <https://karabodevices.pages.xfel.eu/ebpfcat/>`_, which also has
some documentation (notably a
`Troubleshooting section <https://karabodevices.pages.xfel.eu/karahoff/#troubleshooting>`_)

The raspberrys are configured to automatically start Karabo upon boot, so they
should be ready to use once powered on. This also means that in the worst cast,
power cycling should help.

How to set up a new Raspberry Pi
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The only Ethernet port on a Raspberry Pi is reserved for EtherCAT, do not
connect to the network there. Instead, get a USB-to-Ethernet adapter, and
register that one in the network - note that you need to register its MAC
address. For a Revolution PI this already all done - it has two ports, the
right one (labeled "B") is the one for the network, register its MAC address
with ITDM.

Next we need to install Karabo on the Raspberrys. This is done using Ansible,
see the documentation here: https://git.xfel.eu/Karabo/deployment/-/tree/deiter