TX/RX Connections

Projects General Guidance
1

i have a UNO minima and a Arduino NANO , i just want to be sure this connection if good between these two TX/RX Pins , can i go straight between or do i need a Bidirectional Level shifter. thank you

TXRX
TXRX394×207 27.2 KB

2

They both have 5V logic level, so you can connect directly.
Also, serial rx/tx are not bi-directional.

3

So im basically wanting to just send two Pieces of information of data to the NANO a Direction of 1 and an EnableMotor=1 the NANO has the Stepper Motor Code that Controls the motor with AccelStepper
can you give me a small example of sending the data over

4

Have a look at “serial basics” on this forum and there are examples in the IDE .

Note that on the Nano ( at least ) those Rx Tx lines are shared with the USB port .

It might be simpler to just use two digital outputs for your signals - one to show on/off , one for direction .

5

we should be able to use Software Serial Library on both Sides as well correct

   #include <SoftwareSerial.h> 
     
    SoftwareSerial mySerial(10, 11); // RX, TX 
     
    void setup() { 
        Serial.begin(9600); 
        mySerial.begin(9600); 
    } 
     
    void loop() { 
        if (mySerial.available()) { 
            Serial.write(mySerial.read()); // Forward data from mySerial to Serial 
        } 
        if (Serial.available()) { 
            mySerial.write(Serial.read()); // Forward data from Serial to mySerial 
        } 
    }
6

Doesn't the Minima have a separate UART for its tx/rx (1,0) - no softwareserial req'd.?

7

ahh i do believe you are Correct

`The UNO R4 Minima board features two separate hardware serial ports.
One port is exposed via USB-C®, and
One is exposed via RX/TX pins.
This Goes to UART RX/TX

Serial.begin(9600);
Serial.print("hello world");

But im sure the Nano isn't that way

8

I believe it's Serial1 for the former.
Le Nano will 'require' softwareserial.

9

Serial is for data, and it seems a bit charitable to call the above that. You might be better off simply reading pins as Hammy suggests.

10

Another vote for plain digital outputs, if all you need is 2x 1/0.