Industrial Shields Raspberry PLC 19R+, Quick User Manual

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Rev. 8: 29-04-2021
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SPI
The Raspberry PLC pins used for the SPI bus are summarized in the table below. The MISO,
MOSI and CLOCK pins are the same for all the connected devices, while the SS pin, conversely,
will be unique for each one.
Function PLC connection Raspberry board pin
MISO 0 SO GPIO 9
MOSI 0 SI GPIO 10
CLOCK 0 SCK GPIO 11
MISO 1 SO GPIO19
MOSI 1 SI GPIO20
CLOCK 1 SCK GPIO21
Reset Reset Reset
SS SCL/SDA/RX/TX GPIO2/GPIO3/GPIO15/GPIO14
TTL
Raspberry PLC has one TTL ports, RX/TX. TTL is accessed with the function Serial (pins GPIO14
and GPIO15 of the Raspberry PI 4).
Ethernet
Raspberry PLC has two Ethernet ports, eth1 and eth0. The Ethernet port controller is based on
W5500 IC and it generates the eth1 interface, while the eth0 interface is automatically
generated by the Raspberry PI 4.
In the RASPBERRY PLC FAMILY, W5500 IC communicates to the Raspberry PI 4 via SPI1 bus.
If you open a terminal windows, and exec: ip addr, you will see all the network interfaces
working on the Raspberry.
By default, we have a virtual interface with the ip address 10.10.10.20 called eth0:1 . Likewise,
the eth1 has a virtual interface called eth1:1 with the ip address 10.10.11.20 .
In case that you are interested in adding another interface or changing these two ip addresses,
go to the directory where the interfaces are, with the following command:
cd /etc/network/interfaces.d/ and there you will be able to see and edit each interface
configuration.
Finally, in order to check the Ethernet connection of a specific interface, connect the cable of
the Ethernet, and send 4 packets doing a ping to an ip address from the DNS server provided
by Google (8.8.8.8) with the following instruction:
ping -c4 -I (interface name) 8.8.8.8.