kpower
Published © GPL3+

Control your Arduino from your laptop via WiFi with ESP13

Use the ESP 13 Arduino Shield from DOIT (ESP8266) to connect your Arduino to WiFi and control a LED while reading an input voltage

IntermediateFull instructions provided12,458
Control your Arduino from your laptop via WiFi with ESP13

Things used in this project

Hardware components

Arduino UNO
Arduino UNO
×1
ESP-13 ESP8266 Web Sever Serial WiFi Shield Board Module For Arduino UNO R3
×1
Rotary potentiometer (generic)
Rotary potentiometer (generic)
×1
LED (generic)
LED (generic)
×1
Resistor 330 ohm
Resistor 330 ohm
×1

Story

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Schematics

Schematic

Shield Connections

Code

Python Socket Program

Python
Here is the Python 3 program that allows for WiFi communication using a socket
import socket
import tkinter as tk
from tkinter import *
HOST = ''   # Symbolic name, meaning all available interfaces
PORT = 9000 # Arbitrary non-privileged port

# Socket connection is a three step process - create, bind and connect
# Create the socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

#Following routines are defined to handle button events from the GUI
#First routine handles Initialize button event; creates and binds the socket 
def initialize(event):
	entry1.insert (0,'Socket created')
	
	try:
	   s.bind((HOST, PORT))
	except socket.error as msg:
	   entry1.insert ('Bind failed. Error Code : ' + str(msg[0]) + ' Message ' + str(msg[1]))
	   sys.exit()
   
	entry1.insert(END,' Socket bind complete')
	print('Socket bind complete')
	print(s.getsockname())

#Second routine handles Connect button event; connects the ESP13 shield to the socket
#and prints out the IP address of the ESP13 shield	
def connect(event):
	global conn	
	entry2.insert(0,'Socket now listening')
	s.listen()
	conn, addr = s.accept()
	connection = 'Connected with ' + addr[0] + ':' + str(addr[1])
	print('connection ',addr)
	entry2.delete(0,tk.END)
	entry2.insert(0,connection)
	print('connect complete')
	
#Third routine handles Send button event; send the contents of the entry dialog to Arduino
#via ESP13 shield and gets the return message and populates the entry dialog box with the return
#message
def send(event):
	data = entry3.get()
	conn.send(data.encode('utf-8'))
	print('send',data)
	data1 = conn.recv(70)
	entry4.delete(0,tk.END)
	entry4.insert(0,data1)
	
#Fourth routine handles LED Update button event; sends the value of the LED brightness slider
#(+ the arbitary header)to the ESP13
#Reads the return message and updates the potentiometer slider. Dont forget the string to integer conversion
def update(event):
	data = '12#$'
	data = data + str(slider2.get())
	print(data)
	conn.send(data.encode('utf-8'))
	data1 = conn.recv(70)
	slider1.set(int(data1))
	print(data1)
	print('Update LED')

#Final routine handles the Exit button; closes the socket, closes the GUI and exits program
def exit(event):
	s.close()
	print('exit')
	window.destroy()

#All below is tkinter programming to create the GUI. Main window contains two frames, one for entry dialog and sliders
#second for buttons
window = tk.Tk()
window.title("ESP13 Communication")

frame1 = tk.Frame(master=window,relief=tk.FLAT,	borderwidth=5)
frame1.pack()
frame2 = tk.Frame(master=window,relief=tk.FLAT,	borderwidth=5)
frame2.pack()

label1 = tk.Label(master=frame1,text="Socket Ready",fg="black",width = 25,height = 2)
label1.grid(row=0,column=0,padx=20,pady=20,sticky="w")

entry1 = tk.Entry(master=frame1,fg="black",bg="white",width=75)
entry1.grid(row=0,column=1,padx=10,pady=10)

label2 = tk.Label(master=frame1,text="Socket Connected",fg="black",width = 25,height = 2)
label2.grid(row=1,column=0,padx=20,pady=20,sticky="w")

entry2 = tk.Entry(master=frame1,fg="black",bg="white",width=75)
entry2.grid(row=1,column=1,padx=10,pady=10)

label3 = tk.Label(master=frame1,text="Message to send",fg="black",width = 25,height = 2)
label3.grid(row=2,column=0,padx=20,pady=20,sticky="w")

entry3 = tk.Entry(master=frame1,fg="black",bg="white",width=75)
entry3.grid(row=2,column=1,padx=10,pady=10)
entry3.bind("<Return>",send)

label4 = tk.Label(master=frame1,text="Message recieved",fg="black",width = 25,height = 2)
label4.grid(row=3,column=0,padx=20,pady=20,sticky="w")

entry4 = tk.Entry(master=frame1,fg="black",bg="white",width=75)
entry4.grid(row=3,column=1,padx=10,pady=10)

label5 = tk.Label(master=frame1,text="Analog Input",fg="black",width = 25,height = 2)
label5.grid(row=4,column=0,padx=20,pady=20,sticky="w")

slider1 = Scale(frame1, from_=0, to=1023, length=600, orient=HORIZONTAL)
slider1.grid(row=4,column=1,padx=10,pady=10)

label6 = tk.Label(master=frame1,text="LED Brightness",fg="black",width = 25,height = 2)
label6.grid(row=5,column=0,padx=20,pady=20,sticky="w")

slider2 = Scale(frame1, from_=0, to=255, length=600, orient=HORIZONTAL)
slider2.grid(row=5,column=1,padx=10,pady=10)

button1 = tk.Button(master=frame2,text="Initialize",width=10,height=2,relief=tk.RAISED,fg="black")
button1.grid(row=0,column=0,padx=20,pady=20)
button1.bind("<Button-1>",initialize)

button2 = tk.Button(master=frame2,text="Connect",width=10,height=2,relief=tk.RAISED,fg="black")
button2.grid(row=0,column=1,padx=20,pady=20)
button2.bind("<Button-1>",connect)

button3 = tk.Button(master=frame2,text="Send",width=10,height=2,relief=tk.RAISED,fg="black")
button3.grid(row=0,column=2,padx=20,pady=20)
button3.bind("<Button-1>",send)

button4 = tk.Button(master=frame2,text="LED Update",width=10,height=2,relief=tk.RAISED,fg="black")
button4.grid(row=0,column=3,padx=20,pady=20)
button4.bind("<Button-1>",update)

button5 = tk.Button(master=frame2,text="Exit",width=10,height=2,relief=tk.RAISED,fg="black")
button5.grid(row=0,column=4,padx=20,pady=20)
button5.bind("<Button-1>",exit)

window.mainloop()
print('Program ended')

Arduino Sketch

Arduino
Arduino sketch that communicates with ESP13 shield and across WiFi
/*
  Arduino ESP13 Shield Program

  Once the ESP13 shield has connected to a WiFi Network, it sends data over the network from the Arduino that is
  written to the Serial lines. All data that the Arduino sends and recieves over the WiFi network uses the Serial.read, Serial.write
  and Serial.print commands.

  This program receives data from program running on a laptop using the socket connection.

  In order to distinguish beteeen a simple receive / echo case and the LED brightness adjust, a arbitary string "12#$" is transmitted
  as the four beginning bytes. If this is detected, then LED brightness is updated and pot value read from reply. (This string is totally
  arbitary)

  If the header string is not present, then the arduino echos the the message sent.  
*/
String incomingString;
String analogValue;
String headerString;

int ledPin = 3;

void setup() {
  // put your setup code here, to run once
  // Baud rate of ESP13 shield set up in configuration
  Serial.begin(115200);
}

void loop() {
  // reply only when you receive data:
  if (Serial.available() > 0)
  {
    // read the incoming string and strip out four first bytes:
    incomingString = Serial.readString();
    headerString = incomingString.substring(0,4);
    // If the header string equals "12#$" then update LED brightenss and pot value
    if (headerString.equals("12#$"))
    {
      //remove the first four bytes, analogWrite function needs and integer, conversion required
      incomingString.remove(0,4);
      analogWrite(ledPin,incomingString.toInt());
      //read the A0 analog input, convert to string and send back
      analogValue = String(analogRead(A0),DEC);
      Serial.print(analogValue);
    }
    else
    {
    // say what you got:
      Serial.print("ESPRecieved: ");
      Serial.flush();
      Serial.print(incomingString);
    }
  }
  else
  {
    delay(500);    
  }

}

Credits

kpower

kpower

19 projects • 6 followers
Qualified Electrical Engineer with experience in software and hardware development

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Related channels and tags
  • Communication
  • Internet of Things