Connecting RF transmitter and receiver pair to arduino.

Projects Networking, Protocols, and Devices
1

I got this RF tx and rx pair: http://www.bitsbox.co.uk/sensors.html (scroll to the bottom)

here is the datasheet for the transmitter: http://www.bitsbox.co.uk/data/AMRT4_433.pdf

here is the datasheet for the receiver: http://www.bitsbox.co.uk/data/AM-HRR433.pdf

Can someone please guide me as to how i cant connect them to the arduinos and a simple example code maybe?

Thanks in advance.

2

Look for the VirtualWire library.

3

Thankyou, i installed the library and connected my circuits to the arduinos. but there is a problem my transmitter sends a char "hello", but my receiver gets a "Got: 68 65 6C 6C 6F " :confused:

the code for tranmitter:

#include <VirtualWire.h>

void setup()
{
    Serial.begin(9600);	  // Debugging only
    Serial.println("setup");

    // Initialise the IO and ISR
    vw_set_ptt_inverted(true); // Required for DR3100
    vw_setup(2000);	 // Bits per sec
}

void loop()
{
    const char *msg = "hello";

    digitalWrite(13, true); // Flash a light to show transmitting
    vw_send((uint8_t *)msg, strlen(msg));
    vw_wait_tx(); // Wait until the whole message is gone
    digitalWrite(13, false);
    delay(200);
}

receiver:

#include <VirtualWire.h>

void setup()
{
    Serial.begin(9600);	// Debugging only
    Serial.println("setup");

    // Initialise the IO and ISR
    vw_set_ptt_inverted(true); // Required for DR3100
    vw_setup(2000);	 // Bits per sec

    vw_rx_start();       // Start the receiver PLL running
}

void loop()
{
    uint8_t buf[VW_MAX_MESSAGE_LEN];
    uint8_t buflen = VW_MAX_MESSAGE_LEN;

    if (vw_get_message(buf, &buflen)) // Non-blocking
    {
	int i;

        digitalWrite(13, true); // Flash a light to show received good message
	// Message with a good checksum received, dump it.
	Serial.print("Got: ");
	
	for (i = 0; i < buflen; i++)
	{
	    Serial.print(buf[i], HEX);
	    Serial.print(" ");
	}
	Serial.println("");
        digitalWrite(13, false);
    }
}
4

That's because you are printing the received characters as hexadecimal numbers. Try Serial.write(buff[1]).

5

Thankyou but please could you be a bit more specific. where should i put this line?

6

Just a wild guess, but I'd say in place of this

Serial.print(buf*, HEX);*
______
Rob

7

adilmalik:
Thankyou but please could you be a bit more specific. where should i put this line?

In the receiver, change:

	for (i = 0; i < buflen; i++)
	{
	    Serial.print(buf[i], HEX);
	    Serial.print(" ");
	}

to

	for (i = 0; i < buflen; i++)
	    Serial.write(buf[i]);

The second Serial.print() line was there to put spaces between the numbers. Now that there is only one statement inside the 'for' loop statement, the brackets aren't needed anymore.