HC12 assistance needed:

Projects Programming
1

Hello,

I am new to building with Arduino and I am attempting to use one Arduino Nano connected to an HC12 to communicate with another Arduino Nano connected to an HC12. I am trying to write "hello" with an Arduino Nano's HC12 transmitter and read it via the HC12 receiver on another Arduino Nano. When opening the Serial Monitor associated with the receiving Arduino Nano, there is no text whatsoever and no indication that the HC12 modules are working in any way. Is there a separate way to verify that the two HC12 modules are operating appropriately? I have attached screenshots of my code below.

Capture-transmitter.PNG
Capture-transmitter.PNG533×659 16.8 KB

Capture-receiver.PNG
Capture-receiver.PNG558×708 21.8 KB

2

You can find send/receive examples here: GitHub - daar/HC-12: HC-12 library for Arduino

3

Figure-1: Connection diagram between two HC-12 Radio Modules and NANOs

(1) Let us build the setup as per circuit diagram of Fig-1.
(2) Create, compile, and upload the following sketch into the flash of the Master NANO-1. Save the program as hc12-1.

#include <SoftwareSerial.h>
SoftwareSerial HC12(10, 11); //DPin-10 of NANO is its SRX Pin --- HC-12's TXD Pin; 11-RXD
void setup() 
{
  Serial.begin(9600);             // Harware Serial port to computer
  HC12.begin(9600);               // Software Serial port to HC12
}

void loop() 
{
  while (HC12.available())          // If HC-12 has data
  {        
    Serial.write(HC12.read());      // Send the data to Serial Monitor
  }
}

void serialEvent()                  //only for Hard Serail Port
{
  while (Serial.available())        //data from Serial Monitor-1
  {      // If Serial monitor has data
    HC12.write(Serial.read());      // Send that data to HC-12 via Software UART Port
  }
}

(3) Upload the program codes of Step-2 into the flash of NANO-2.
(4) Bring in SM1 for UNO-1.
(5) Bring in SM2 for UNO-2.
(6) In the inputBox of SM1, enter "Hello!" and and click the Send button. Check that "Hello!" has appeared on the SM2 of NANO-2.
(7) In the InputBox of SM2, enter "Fine!" and click the Send button. Check that "Fine!" has appeared on SM1.