Queries regarding RF transmitter receiver module

Projects General Guidance
1

Hi guys, I'm making an RF bot and I want to know if I could send alphabets like 'w', 'a' etc. via the transmitter or only binary digits (0, 1). Also, I'm looking forward to solder a wire as an antenna. Is it helpful to hook up a wire as an antenna? Thanks for all the help :slight_smile: . Here's my code

//Transmitter Code (Nano)
#include <VirtualWire.h>

void setup()
{
  Serial.begin(9600);
  
  vw_setup(2000);
  vw_set_tx_pin(7);
}

void loop()
{
  if(Serial.available())
  {
    char c = Serial.read();
    
    if(c == 'w')
    {
      vw_send((uint8_t *)c, 1);
    }
    else if(c == 's')
    {
      vw_send((uint8_t *)c, 1);
    }
    else if(c == 'a'){
      vw_send((uint8_t *)c, 1);
    }
    else if(c == 'd')
    {
      vw_send((uint8_t *)c, 1);
    }
    else if (c == 'x'){
      vw_send((uint8_t *)c, 1);
    }
    
  }
}

//Reciever Code (Uno)
#include <VirtualWire.h>
#include <AFMotor.h>
AF_DCMotor motor1(1);
AF_DCMotor motor2(2);


void setup()
{
motor1.setSpeed(175);
motor2.setSpeed(175);
  
  vw_setup(2000);
  vw_set_rx_pin(7);
  vw_rx_start();
}

void loop()
{
  uint8_t buflen = VW_MAX_MESSAGE_LEN;
  uint8_t buf[buflen];
  
  if(vw_get_message(buf, &buflen))
  {
    for(int i = 0;i < buflen;i++)
    {
      if(buf[i] == 'w')
      {
        motor1.run(FORWARD);
        motor2.run(FORWARD);
      }
      else if(buf[i] == 'a')
      {
        motor1.run(BACKWARD);
        motor2.run(FORWARD);
        
      }
      else if (buf[i] == 's') {
        motor1.run(BACKWARD);
        motor2.run(BACKWARD);
      }
      else if(buf[i] == 'd'){
        motor1.run(FORWARD);
        motor2.run(BACKWARD);
    }
    else if(buf[i] == 'x'){
      motor1.run(RELEASE);
      motor2.run(RELEASE);
    }
  }
  }
}
2

Hi,
What RF units are you using?
An antenna wire will make quite a difference.

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Tom.... :slight_smile:

3

Thanks , here is my module(attachment)
As far as the circuit goes, I am planning right now so I'll provide it in a day or two.
Also, can I use letters or do I have to use binary digits.

$_12.jpg

4

ecgeek:
Thanks , here is my module(attachment)

Also, can I use letters or do I have to use binary digits.

For those, you may find this to be of use. Author (he's a forum member too) provides a protocol for sending actual messages and has a sketch for each end, Rx and Tx.

5

Image from Reply #2 so we don't have to download it. See Image Guide

a44b85aad0b15841a7386aa243bbde465a86cd18.jpg

...R