Industrial Shields Raspberry PLC 19R+, Быстрое руководство пользователя

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Rev. 8: 29-04-2021
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For the Analog Shield if a switch is set to ON, it can only act as Digital Output. If it is set to OFF,
it can only act as an Analog Output.
If it is desired to use a Digital Output the pin must be set to ON and the pin that will provide
this digital output is represented with QX.X, being X any number of the tables above.
If it is desired to use an Analog Output the pin must be set to OFF and the pin that will provide
this analog output is represented with AX.X, being X any number of the tables above.
I/O RASPBERRY PLC 3.3V pins
The RASPBERRY PLC FAMILY has some of the Raspberry PI 4 board pins available. These pins
can be programmed according to Raspberry features such as I/O
’ s operating at 3.3V or any
additional features present in the pins (for example I2C communication in pins SCL and SDA).
As these pins are directly connected to the Raspberry PI 4 board, they are not as well
protected as the normal inputs. These pins are mainly meant to be used as prototyping.
The Raspberry board available pins are summarized in the table below. In order to access to
these pins some extra considerations must be taken in consideration.
*IMPORTANT: Do not connect the terminals in the chart above to voltages higher than 3.3V.
These terminals provide direct access to the Raspberry board.
There are some special conditions depending on these 3.3V. Now it is going to be shown the
considerations to operate with these pins.
Serial – RX/TX
The Serial protocol can work also as a 3.3V pin. These pins should be used only in case that all
the 3.3V pins are already performing a function. If using both interfaces at
the
same time the
Raspberry board will get blocked.
These pins are not established with a pull-up or a pull-down configuration by default. The
Arduino board allows the pins to be set in a pull-up configuration. Otherwise, an external pull-
up or pull-down circuit could be set.
PLC terminal Raspberry pin
TX GPIO 14
RX GPIO 15
MISO 0 GPIO 9
MOSI 0 GPIO 10
SCLK 0 GPIO 11
GPIO25 GPIO 25