HM10 Bluetooth Data

Projects Programming
1

Hi everyone,
I am trying to send and receive data using HM-10 Bluetooth modules. The following is the code that I use from a tutorial (HM-10 Bluetooth 4 BLE Modules | Martyn Currey). The first is the code for the peripheral module and the other is the central module. I have also manually connected the two modules via AT commands (also setting the central module to role1 and the other to role0) and both modules are showing a solid red light when powered. However, in the peripheral code, using the Serial.println(Serial.read()) line, it shows that the peripheral only receives -1. Anyone knows what could have went wrong?

#include <AltSoftSerial.h>
AltSoftSerial BTSerial; 
 
char c=' ';
byte LEDpin = 13;
 
void setup() 
{
    Serial.begin(9600);
    BTSerial.begin(9600);  

    pinMode(LEDpin, OUTPUT); 
    digitalWrite(LEDpin,HIGH); 
}
 
void loop()
{
  Serial.println(Serial.read());
    if (BTSerial.available())
    {
        Serial.println("HERE");
        c = BTSerial.read();
        Serial.println(c);

        if (c==49)   { digitalWrite(LEDpin,HIGH);   }
        if (c==48)   { digitalWrite(LEDpin,LOW);    }
        Serial.println(c);
    }
 
}

#include <AltSoftSerial.h>
AltSoftSerial BTserial; 
 
byte switchPin = 2;
boolean switch_State = LOW;
boolean oldswitch_State = LOW;
 
void setup() 
{
    Serial.begin(9600);
    BTserial.begin(9600);
 
    pinMode(switchPin, INPUT); 
 
    // connect to the remote Bluetooth module
    BTserial.print("AT+IMME1" );
    delay(1000);    
    BTserial.print("AT+ROLE1" );
    delay(1000);
    BTserial.print("AT+CON4C3FD302B298" );
    delay(1000);
 
}
 
void loop()
{
    // Very simple debouce.
    boolean state1 = digitalRead(switchPin); delay(1);
    boolean state2 = digitalRead(switchPin); delay(1);
    boolean state3 = digitalRead(switchPin); delay(1);
    if ((state1 == state2) && (state1==state3))  
    { 
        switch_State = state1;  
 
        if (switch_State != oldswitch_State)
        {
              if ( switch_State == HIGH) { BTserial.print("1" );  Serial.println("1"); Serial.write("1");}
              else                       { BTserial.print("0" );  Serial.println("0"); Serial.write("0");}
 
              oldswitch_State = switch_State;
        }
    }
}
2 
  Serial.println(Serial.read());

Why would you do this?

Instead of messing around with switches that may not be wired correctly, the sender should periodically send a KNOWN string (that can be just one character long).

You really need to understand what print(), println(), and write() do, and when you need to use each one.

3

I was trying to check if the BLE module was receiving anything. It never gets into the if (BTSerial.available()) loop and this is from a tutorial. Even without doing that, the BLE modules don't transfer data among each other although the lights are solid red. I have also verified that the buttons are connected correctly because I have tested it using LEDs already. Any help is appreciated.