Datasheet

Ref. IS.MDUINO.XXX
9.5 Pin 2/Pin 3
These pins are only referred to the inputs I0.5/I0.6. If the switch configuration is in OFF
position the pins Pin 2/Pin 3 will be available.
These pins are not stablished with a pull-up or a pull-down configuration. The state of these
pins is unknown. If these pins must be used, they require a pull-up or a pull-down
configuration. The Arduino board allows the pins to be set in a pull-up configuration. If not it
must be stablished an external pull-up or pull-down circuit in order to correctly work with
these pins.
A Zone Features: Communications & RTC & uSD
10.1 RS-232
The Arduino Mega function code to access the RS-232 port in the M-Duino is Serial2 (pins 16
and 17 of the Arduino Mega).
For the RS-232 communication protocol there isn’t any switch that affects it. So it does not
matter the configuration of the switches to implement a RS-232 communication.
Using the boards of Industrial Shields, there is a library that simplifies the RS-232
implementation.
10.2 RS-485
For RS485 communication protocol the defined Arduino Mega pins are showed in the chart
below.
Function
Arduino Pin
DI
14
RO
15
RE
11
DE
46
For the RS-485 communication protocol there is only one switch that affects in this
communication. The RS-485 protocol will be always enabled, the only switch that affects is the
one called “FD rs-485 HD” (See Section 8). This switch makes the choosing between RS-485
Half Duplex or RS-485 Full Duplex (RS-422).
Using the boards of Industrial Shields, there is a library that simplifies the RS-485
implementation.