Wireless Communication Using Arduino and RF Module

1#include <VirtualWire.h>
2#include <Wire.h> //IIC Library
3#include <LiquidCrystal_I2C.h>//For the screen
4#include <elapsedMillis.h>//For the Status
5LiquidCrystal_I2C lcd(0x3F,20,4);  // set the parameters
6boolean constat=1;//Status Variable 1=On at start, 0=off at start
7int line;//Status code moves cursor, variable to store DESIRED line number 
8boolean splashcleared;//Bool to hold if splash screen has been cleared
9String text = " ";//String to hold the text
10elapsedMillis packettimer;//The timer for status
11#define interval 1500//The threshold for how long it can go without "6"(The connection indicator)
12
13//initialize the symbols
14 
15
16void setup()
17{
18  pinMode(12, OUTPUT); //Module VCC 
19  digitalWrite(12, HIGH);   // turn the VCC to High 
20  vw_set_rx_pin(11);// set you rx pin
21  vw_setup(2500);	 // Bits per sec. Lower for further distance. Make sure this matches the number on the transmitter
22  vw_rx_start();       // Start the receiver PLL running
23  splashcleared=0;//make sure that this is 0
24  lcd.init();//start the screen
25  //initialize the symbols 
26  //setCursor comands note- Counting starts at 0 NOT 1
27  lcd.createChar(0, cchar); //Rf symbol
28  lcd.createChar(1, bar1); //Bar 1 and 2
29  lcd.createChar(2, bar2); //Bar 3 and 4
30  Serial.begin(9600);//Open serial port, add the !serial thing for leonardo
31  lcd.backlight();//Turn on the backlight
32  lcd.clear();//Clear the screen
33  lcd.home();//go home
34
35    //display Home screen This will be cleared once The siglal indicator "6" is sent
36  lcd.setCursor (5,0);
37  lcd.print("RF--Screen"); 
38  lcd.setCursor (0,1); 
39  lcd.print("By ICARUS"); 
40  lcd.setCursor (0,2);
41  lcd.print("Connection Status-"); 
42  lcd.setCursor (0,3);
43  lcd.print("Inactive"); 
44  delay (1200);//set this to the interval
45}
46
47
48  void loop()
49  {
50    uint8_t buf[VW_MAX_MESSAGE_LEN];
51    uint8_t buflen = VW_MAX_MESSAGE_LEN;
52
53
54    if (packettimer< interval){//It the status of the connection is good and "6" was recieved in the last 1.5 secs.
55      if (splashcleared==0){//if screen hasn't been cleared of status
56        lcd.clear();//clear it
57        splashcleared=1;//make sure it won't be again  
58      } 
59    }//make sure the screen wont clear again
60
61
62    if (constat==1){  //If the status bar is enabled
63      if (packettimer< interval){//It the status of the connection is good and "6" was recieved in the last 1.5 secs.
64
65        lcd.setCursor (17,0); //go to 3rd last position    
66        lcd.write(0); //RF symbol
67        lcd.write(1);//bar one
68        lcd.write(2);//Bar two
69      }
70
71      else if (packettimer > interval) {//It the status of the connection is bad and "6" was not recieved in the last 1.5 secs.
72        //we will blink a X by the rf symbol
73        lcd.setCursor (17,0);//go to 3rd last position  
74        lcd.write(0);  //RF symbol    
75        lcd.setCursor (18,0);//go to 2nd last position 
76        lcd.print ("X ");//To add the X
77        delay (450);// wait
78        lcd.setCursor (18,0);////go to 2nd last position 
79        lcd.print ("  ");//To erase the X
80        delay (400);//wait
81
82      }
83    }
84
85
86    if (vw_get_message(buf, &buflen)) // Non-blocking
87    {
88      packettimer = 0;//Reset timer when data is recieved
89      text.remove(0);//clear all text from string: text
90      text=(char*)buf;//put new data into string "text"
91
92
93      text.remove(buflen-1);//Remove garbage after the end of the text
94      lcd.setCursor(0,line);//Restore cursor to original position
95      //Most of these commands are self explanitory...
96
97      if (text.startsWith("1")) {
98        lcd.setCursor(0,0);
99        line=0;
100      } 
101
102      else if (text.startsWith("2")) {
103        lcd.setCursor(0,1);
104        line=1;
105
106      } 
107      else if (text.startsWith("3")) {
108        lcd.setCursor(0,2);
109        line=2;
110
111      } 
112      else if (text.startsWith("4")) {
113        lcd.setCursor(0,3);
114        line=3;
115
116      }
117      else if (text.startsWith("clear")) {
118        lcd.clear();
119      } 
120      else if (text.startsWith("6")) {//"6" is sent every 300 ms to check the signal, and we dont want it to display
121        packettimer = 0;//Reset timer when data is recieved
122        if (splashcleared==0){//if screen hasn't been cleared of status
123          lcd.clear();
124          splashcleared=1;//make sure the screen wont clear again
125        }  
126      }
127      else if (text.startsWith("backlight")) {
128        lcd.backlight();
129      } 
130      else if (text.startsWith("nobacklight")) {
131        lcd.noBacklight();
132      }  
133      else if (text.startsWith("status")) {
134        lcd.setCursor (17,0);//Go to the third last spot
135        lcd.write(0);//Show the Rf symbol
136        lcd.write(1);//Show bar set 1
137        lcd.write(2);//Show bar set 2
138        constat=1;//(ConnectionStatus)this variable will make the signal show
139      } 
140      else if (text.startsWith("nostatus")) {
141        lcd.setCursor (17,0);//Go to the third last spot
142        lcd.print ("   ");//write it over with 3 spaces
143        constat=0;//(ConnectionStatus)this variable will block the signal from showing
144
145      }
146
147      else if (text.startsWith("{")) {//if we want to sen a command word to display on screen, we precede it with{
148        text.remove (1); //remove the"{", This must be second last of if statements
149      } 
150      else {//this MUST be last statement
151        packettimer = 0;//Reset timer when data is put onto the screen
152        lcd.setCursor(0,line);//Go to the specified line
153        lcd.print(text);//If word isn't a command print it
154      }
155
156    }
157  }

1#include <Wire.h>
2 
3void setup()
4 {
5   Wire.begin();
6 
7  Serial.begin(115200);
8   Serial.println("\nI2C Scanner");
9 }
10 
11void loop()
12 {
13   byte error, address;
14   int nDevices;
15 
16  Serial.println("Scanning...");
17 
18  nDevices = 0;
19   for(address = 0; address <= 127; address++ )
20  {
21     // The i2c_scanner uses the return value of
22     // the Write.endTransmisstion to see if
23     // a device did acknowledge to the address.
24     Wire.beginTransmission(address);
25     error = Wire.endTransmission();
26 
27    if (error == 0)
28     {
29       Serial.print("I2C device found at address 0x");
30       if (address<16)
31        Serial.print("0");
32       Serial.print(address,HEX);
33       Serial.println(" !");
34 
35      nDevices++;
36     }
37     else if (error==4)
38    {
39       Serial.print("Unknow error at address 0x");
40       if (address<16)
41        Serial.print("0");
42       Serial.println(address,HEX);
43     }
44   }
45   if (nDevices == 0)
46     Serial.println("No I2C devices found\n");
47   else
48     Serial.println("done\n");
49 
50  delay(8000);           // wait 8 seconds for next scan
51 }

1#include <VirtualWire.h>
2#include <elapsedMillis.h> //For the status on the reciever
3
4String serialdata; //Holds data coming in
5char msg[50]; //Char array to send data out with
6String statustext="6"; //This is the text sent every interval
7elapsedMillis packettimer;//this is the timer
8#define interval 50//Lower this if you send long packets
9
10void setup()
11{
12  pinMode(8, OUTPUT);//Module GND
13  pinMode(9, OUTPUT); //Module VCC 
14  digitalWrite(9, HIGH);   // turn the VCC to HIGH, set to LOW for default off
15  digitalWrite(8, LOW);   // turn the GND to LOW 
16  vw_set_tx_pin(10);
17  vw_setup(2500);       // Bits per sec
18  Serial.begin(9600);
19  packettimer = 0;//Reset the timer
20  Serial.println ("Serial Port Open");
21}
22
23void loop()
24{
25
26  if (Serial.available()){
27    delay (50);
28    Serial.println ("I found Serial Data");// If you are having issues, these will help you find where your code doesnt work.
29    serialdata=Serial.readString();//put text from serial in serialdata string
30
31      if (serialdata.startsWith("off")) {
32      digitalWrite(9, LOW);   // turn the VCC to LOW
33      digitalWrite(8, LOW);   // turn the GND to LOW 
34      Serial.println("");     
35      Serial.println("Module OFF"); 
36      Serial.println("");  
37    } 
38    else if (serialdata.startsWith("on")) {
39      digitalWrite(9, HIGH);   // turn the VCC to HIGH 
40      digitalWrite(8, LOW);   // turn the GND to LOW 
41      Serial.println("");
42      Serial.println("Module ON");
43      Serial.println("");  
44    } 
45
46    else {
47
48      serialdata.toCharArray(msg, 50);//convert serialdat the the msg char array
49      Serial.println ("I converted it to a CHAR ARRAY");
50      Serial.println("Text to be Sent-");//debugging
51      Serial.println("");//debugging
52      Serial.print(msg);//debugging
53      Serial.println("");//debugging
54      vw_send((uint8_t *)msg, strlen(msg));
55      vw_wait_tx();
56      Serial.println ("MSG send request");
57      // driver.waitPacketSent();//wait until it is sent
58      Serial.println ("Data Sent");
59    }
60  }
61
62  if (packettimer > interval) {
63
64    statustext.toCharArray(msg, 50);//convert the statustext string to msg char array
65    vw_send((uint8_t *)msg, strlen(msg)); //line that sends the msg variable
66    vw_wait_tx();//wait untill sent
67  }
68}
69//Code mainly From Arduino.cc and VW examples