Tag Archives: UDP

In this lesson we are working on a client server connection. The Arduino is the server, and a python program on a desktop PC is the client. The objective is to control the color of an RGB LED from the client. The client will send data to the server as comma delimited string, like 255,0,255 for RGB. The challenge on the server side is to parse this data so we get integer values of:

R=255

G=0

B=255

In this video lesson we start by simply controlling two LED, a red and green one, from the python client. We then show how we can control an RGB LED by sending the data string from the client, and parsing it on the server side. For your convenience, we include the code here:

Server Side code for the Arduino:

#include <WiFiS3.h>
#include "secrets.h"
WiFiUDP udp;
int PORT = 12345;
char myPacket[255];
int dataLen;
String color;
String response;
int redPin = 8;
int greenPin = 9;
int R;
int G;
int B;
int firstComma;
int secondComma;
void setup() {
  Serial.begin(9600);
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  Serial.print("Connecting to ");
  Serial.println(SSID);
  WiFi.begin(SSID, PASS);
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println("\nConnected to WiFi");
  Serial.println(WiFi.localIP());
  udp.begin(PORT);
  Serial.print("UDP Server started on port ");
  Serial.print(PORT);
  // put your setup code here, to run once:
}

void loop() {
  // put your main code here, to run repeatedly:
  if (udp.parsePacket()) {
    dataLen = udp.available();
    Serial.println(dataLen);
    udp.read(myPacket, 255);
    Serial.println(myPacket);
    myPacket[dataLen] = 0;
    Serial.println(myPacket);
    color = String(myPacket);
    color.trim();
    Serial.println("Received color: " + color);
    firstComma=color.indexOf(',',0);
    secondComma=color.indexOf(',',firstComma+1);
    R=color.substring(0,firstComma).toInt();
    G=color.substring(firstComma+1,secondComma).toInt();
    B=color.substring(secondComma+1).toInt();
    Serial.println(R);
    Serial.println(G);
    Serial.println(B);
    udp.beginPacket(udp.remoteIP(), udp.remotePort());
    udp.print(response);
    udp.endPacket();
    Serial.println("SENT: " + response);
  }
}

#include <WiFiS3.h>

#include "secrets.h"

WiFiUDP udp;

int PORT = 12345;

char myPacket[255];

int dataLen;

String color;

String response;

int redPin = 8;

int greenPin = 9;

int R;

int G;

int B;

int firstComma;

int secondComma;

void setup() {

Serial.begin(9600);

pinMode(redPin, OUTPUT);

pinMode(greenPin, OUTPUT);

Serial.print("Connecting to ");

Serial.println(SSID);

WiFi.begin(SSID, PASS);

while (WiFi.status() != WL_CONNECTED) {

delay(100);

Serial.print(".");

}

Serial.println("\nConnected to WiFi");

Serial.println(WiFi.localIP());

udp.begin(PORT);

Serial.print("UDP Server started on port ");

Serial.print(PORT);

// put your setup code here, to run once:

}

void loop() {

// put your main code here, to run repeatedly:

if (udp.parsePacket()) {

dataLen = udp.available();

Serial.println(dataLen);

udp.read(myPacket, 255);

Serial.println(myPacket);

myPacket[dataLen] = 0;

Serial.println(myPacket);

color = String(myPacket);

color.trim();

Serial.println("Received color: " + color);

firstComma=color.indexOf(',',0);

secondComma=color.indexOf(',',firstComma+1);

R=color.substring(0,firstComma).toInt();

G=color.substring(firstComma+1,secondComma).toInt();

B=color.substring(secondComma+1).toInt();

Serial.println(R);

Serial.println(G);

Serial.println(B);

udp.beginPacket(udp.remoteIP(), udp.remotePort());

udp.print(response);

udp.endPacket();

Serial.println("SENT: " + response);

}

The code above needs a ‘secrets.h’ file which includes your WiFi name and password. This is created in the IDE by choosing ‘Add Tab’. Call the new tab ‘secrets.h’, and edit the code below to include your WiFi name and passwords inside the quotes:

#define SSID "Your WiFi Name"
#define PASS "Your WiFi Password"

1 2	#define SSID "Your WiFi Name" #define PASS "Your WiFi Password"

Now, on the client side, this is our standard Python client:

import socket

# Arduino’s IP address (from Arduino Serial Monitor)
HOST = "192.168.88.77"  # Use Your Arduino's IP. It will print when
                        #You Run the Arduino Server Program
PORT = 12345            # Must match Arduino’s UDP port

# Create a UDP socket
mySocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
mySocket.settimeout(5.0)  # 5 seconds timeout for responses

print("UDP Client started. Enter a color (or 'quit' to exit).")

while True:
    # Prompt for a color
    #color = input("Enter a color: ").strip()  # Remove whitespace
    color = input("Enter a color: ") 
    if color.lower() == 'quit':  # Exit condition
        break

    # Send the color to the server
    sendColor=color.encode()
    mySocket.sendto(sendColor, (HOST, PORT))
    print('Sent '+color+' to HOST',HOST,PORT)

    # Try to get a response, skip on timeout
    try:
        response, server_address = mySocket.recvfrom(1024)
        print("Server response:", response.decode())
    except socket.timeout:
        print("No response received from server within 5 seconds")

# Close the socket
mySocket.close()
print("Socket closed")

import socket

# Arduino’s IP address (from Arduino Serial Monitor)

HOST = "192.168.88.77" # Use Your Arduino's IP. It will print when

#You Run the Arduino Server Program

PORT = 12345 # Must match Arduino’s UDP port

# Create a UDP socket

mySocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

mySocket.settimeout(5.0) # 5 seconds timeout for responses

print("UDP Client started. Enter a color (or 'quit' to exit).")

while True:

# Prompt for a color

#color = input("Enter a color: ").strip() # Remove whitespace

color = input("Enter a color: ")

if color.lower() == 'quit': # Exit condition

break

# Send the color to the server

sendColor=color.encode()

mySocket.sendto(sendColor, (HOST, PORT))

print('Sent '+color+' to HOST',HOST,PORT)

# Try to get a response, skip on timeout

try:

response, server_address = mySocket.recvfrom(1024)

print("Server response:", response.decode())

except socket.timeout:

print("No response received from server within 5 seconds")

# Close the socket

mySocket.close()

print("Socket closed")

With this code for creating a client and server, and then parsing comma delimited text, you can easily add the code needed to control the RGB LED color to the arduino program.

Arduino, Python

Create a Simple Client Server Connection Over WiFi to Connect Arduino to Python on the PC

April 24, 2025 admin

In this video lesson, we show how to create a simple Client/Server connection over WiFi. We connect the Arduino Uno R4 WiFi to Python running on the PC. The arduino is the server, and the PC Python program is the client. We show how to pass data from the PC to the Arduino, and then how to pass data from the Arduino back to the PC. With this simple framework, we can control Arduino projects from our desktop PC, and we can use the PC to display data being taken from the Arduino.

In this lesson we develop code for Arduino, and the code in Python. For your convenience, we present the code below.

On the Arduino Side, this is the code to create the ‘Server’.

#include <WiFiS3.h>
#include "secrets.h"
WiFiUDP udp;
int PORT = 12345;
char myPacket[255];
int dataLen;
String color;
String response;
void setup() {
  Serial.begin(9600);
  Serial.print("Connecting to ");
  Serial.println(SSID);
  WiFi.begin(SSID, PASS);
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println("\nConnected to WiFi");
  Serial.println(WiFi.localIP());
  udp.begin(PORT);
  Serial.print("UDP Server started on port ");
  Serial.print(PORT);
  // put your setup code here, to run once:
}

void loop() {
  // put your main code here, to run repeatedly:
  if (udp.parsePacket()) {
    dataLen = udp.available();
    Serial.println(dataLen);
  udp.read(myPacket,255);
  Serial.println(myPacket);
  myPacket[dataLen]=0;
  Serial.println(myPacket);
  color=String(myPacket);
  color.trim();
  Serial.println("Received color: "+color);
  response ="Here is your "+color+" Marble";  
 udp.beginPacket(udp.remoteIP(), udp.remotePort());
 udp.print(response);
 udp.endPacket();
  Serial.println("SENT: "+response);
  }
}

#include <WiFiS3.h>

#include "secrets.h"

WiFiUDP udp;

int PORT = 12345;

char myPacket[255];

int dataLen;

String color;

String response;

void setup() {

Serial.begin(9600);

Serial.print("Connecting to ");

Serial.println(SSID);

WiFi.begin(SSID, PASS);

while (WiFi.status() != WL_CONNECTED) {

delay(100);

Serial.print(".");

}

Serial.println("\nConnected to WiFi");

Serial.println(WiFi.localIP());

udp.begin(PORT);

Serial.print("UDP Server started on port ");

Serial.print(PORT);

// put your setup code here, to run once:

}

void loop() {

// put your main code here, to run repeatedly:

if (udp.parsePacket()) {

dataLen = udp.available();

Serial.println(dataLen);

udp.read(myPacket,255);

Serial.println(myPacket);

myPacket[dataLen]=0;

Serial.println(myPacket);

color=String(myPacket);

color.trim();

Serial.println("Received color: "+color);

response ="Here is your "+color+" Marble";

udp.beginPacket(udp.remoteIP(), udp.remotePort());

udp.print(response);

udp.endPacket();

Serial.println("SENT: "+response);

}

You also need to add a tab to your program using the ‘Add Tab’ feature of the IDE. The program in the tab should be named secrets.h

Your secrets.h file should look like this:

#define SSID "Your WiFi Name"
#define PASS "your Wifi Password"

1 2	#define SSID "Your WiFi Name" #define PASS "your Wifi Password"

You can run the program above, and it should connect to your WiFi, and should print out the Arduino’s IP address. Make note of the IP address as it will be needed in the Client program below. On the PC side, this is the python code to create the client:

import socket

# Arduino’s IP address (from Arduino Serial Monitor)
HOST = "192.168.88.77"  # Use Your Arduino's IP. It will print when
                        #You Run the Arduino Server Program
PORT = 12345            # Must match Arduino’s UDP port

# Create a UDP socket
mySocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
mySocket.settimeout(5.0)  # 5 seconds timeout for responses

print("UDP Client started. Enter a color (or 'quit' to exit).")

while True:
    # Prompt for a color
    #color = input("Enter a color: ").strip()  # Remove whitespace
    color = input("Enter a color: ") 
    if color.lower() == 'quit':  # Exit condition
        break

    # Send the color to the server
    sendColor=color.encode()
    mySocket.sendto(sendColor, (HOST, PORT))
    print('Sent '+color+' to HOST',HOST,PORT)

    # Try to get a response, skip on timeout
    try:
        response, server_address = mySocket.recvfrom(1024)
        print("Server response:", response.decode())
    except socket.timeout:
        print("No response received from server within 5 seconds")

# Close the socket
mySocket.close()
print("Socket closed")

import socket

# Arduino’s IP address (from Arduino Serial Monitor)

HOST = "192.168.88.77" # Use Your Arduino's IP. It will print when

#You Run the Arduino Server Program

PORT = 12345 # Must match Arduino’s UDP port

# Create a UDP socket

mySocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

mySocket.settimeout(5.0) # 5 seconds timeout for responses

print("UDP Client started. Enter a color (or 'quit' to exit).")

while True:

# Prompt for a color

#color = input("Enter a color: ").strip() # Remove whitespace

color = input("Enter a color: ")

if color.lower() == 'quit': # Exit condition

break

# Send the color to the server

sendColor=color.encode()

mySocket.sendto(sendColor, (HOST, PORT))

print('Sent '+color+' to HOST',HOST,PORT)

# Try to get a response, skip on timeout

try:

response, server_address = mySocket.recvfrom(1024)

print("Server response:", response.decode())

except socket.timeout:

print("No response received from server within 5 seconds")

# Close the socket

mySocket.close()

print("Socket closed")

Python, Raspberry Pi Pico

Remotely Control a DC Motor Over WiFi With Raspberry Pi Pico W

April 15, 2025 admin

In this video lesson I will show you how you can control a remote DC motor using your Raspberry Pi Pico W. The Pi Pico is set up as a server, and is connected to a DC motor, and TA6586 Motor Controller. The motor is controlled by a client Python program running on your desktop PC. On the client side we create a Graphical Widget, which will allow you to control both the speed and direction of the motor. the schematic for the Raspberry Pi Pico W side is shown below:

Motor Controller — Schematic for TA6586 and Raspberry Pi Pico DC Motor Control

When using the breadvolt, or any battery power supply on a breadboard project, do not turn the power supply on while the Raspberry Pi Pico is connected to USB, as you could generate voltage conflicts. It is an either or. If the USB is connected, the power supply should be OFF. Or if you are going to connect the USB, first turn off the power supply.

Then in the video, we developed the following software for the server side on the Pi Pico

import network
import usocket as socket
import secrets
import time
from machine import Pin, PWM
icPin1=Pin(14,Pin.OUT)
icPin2=Pin(15,Pin.OUT)
fPWM=PWM(icPin1)
rPWM=PWM(icPin2)
fPWM.freq(1000)
rPWM.freq(1000)

wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(secrets.SSID,secrets.PASSWORD)

# Wait for connection
while not wlan.isconnected():
    time.sleep(1)
print("Connection Completed")
print('WiFi connected')
print(wlan.ifconfig())

# Set up UDP server
server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.bind((wlan.ifconfig()[0], 12345))
print("Server is Up and Listening")

while True:
    print('Waiting for a request from the client...')
    # Receive request from client
    request, client_address = server_socket.recvfrom(1024)
    request=request.decode()
    print("Client Request:",request)
    print("FROM CLIENT",client_address)
    cmdArray=request.split(',')
    motorState=cmdArray[0]
    speed=int(cmdArray[1])
    rPWM.duty_u16(0)
    fPWM.duty_u16(0)
    if motorState == 'O':
        rPWM.duty_u16(0)
        fPWM.duty_u16(0)
    if motorState == 'F':
        rPWM.duty_u16(0)
        fPWM.duty_u16(int(speed/100*65535))
    if motorState == 'R':
        fPWM.duty_u16(0)
        rPWM.duty_u16(int(speed/100*65535))
    # String to send
    data =request +" CMD PROCESSES+D"
    
    # Send data to client
    server_socket.sendto(data.encode(), client_address)
    print(f'Sent data to {client_address}')

import network

import usocket as socket

import secrets

import time

from machine import Pin, PWM

icPin1=Pin(14,Pin.OUT)

icPin2=Pin(15,Pin.OUT)

fPWM=PWM(icPin1)

rPWM=PWM(icPin2)

fPWM.freq(1000)

rPWM.freq(1000)

wlan = network.WLAN(network.STA_IF)

wlan.active(True)

wlan.connect(secrets.SSID,secrets.PASSWORD)

# Wait for connection

while not wlan.isconnected():

time.sleep(1)

print("Connection Completed")

print('WiFi connected')

print(wlan.ifconfig())

# Set up UDP server

server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

server_socket.bind((wlan.ifconfig()[0], 12345))

print("Server is Up and Listening")

while True:

print('Waiting for a request from the client...')

# Receive request from client

request, client_address = server_socket.recvfrom(1024)

request=request.decode()

print("Client Request:",request)

print("FROM CLIENT",client_address)

cmdArray=request.split(',')

motorState=cmdArray[0]

speed=int(cmdArray[1])

rPWM.duty_u16(0)

fPWM.duty_u16(0)

if motorState == 'O':

rPWM.duty_u16(0)

fPWM.duty_u16(0)

if motorState == 'F':

rPWM.duty_u16(0)

fPWM.duty_u16(int(speed/100*65535))

if motorState == 'R':

fPWM.duty_u16(0)

rPWM.duty_u16(int(speed/100*65535))

# String to send

data =request +" CMD PROCESSES+D"

# Send data to client

server_socket.sendto(data.encode(), client_address)

print(f'Sent data to {client_address}')

Then for the client side, the following program runs on Python on your PC:

import socket
import time
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import sys
speedF=0
speedR=0
motorStatus='O'

# Set up UDP client
client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
client_socket.settimeout(1)
server_address = ('192.168.88.19', 12345)  # Adjust IP address and port as needed

app=QApplication(sys.argv)
window=QWidget()
window.setWindowTitle("Big Boss Motor Controller")
window.setGeometry(100,100,800,600)
mainLayout=QHBoxLayout(window)
leftLayout=QVBoxLayout()
rightLayout=QVBoxLayout()

def updateMotor():
    global motorStatus,speedF,speedR
    try:
        print(motorStatus)
        if motorStatus=='F':
            cmd=motorStatus+','+str(speedF)
        if motorStatus=='R':
            cmd=motorStatus+','+str(speedR)
        if motorStatus=='O':
            cmd=motorStatus+','+str(0)

        client_socket.sendto(cmd.encode(), server_address)
        data, addr = client_socket.recvfrom(1024)
        print('Received data:', data.decode())
        
    except:
        print("Server Did Not Respond, Try Again")


def updateForSpeed(value):
    global speedF
    speedF=value
    print(speedF)
def updateRevSpeed(value):
    global speedR
    speedR=value
    print(speedR)
def motorGo():
    global motorStatus
    motorStatus = 'F'
    print("GO")
def motorRev():
    global motorStatus
    motorStatus = 'R'
    print("REV")
def motorStop():
    global motorStatus
    motorStatus = 'O'
    print("STOP")


sliderLabelF=QLabel("Forward Speed")
sliderLabelF.setStyleSheet("font-size: 20px;")
leftLayout.addWidget(sliderLabelF)

sliderF=QSlider(Qt.Vertical)
sliderF.setMinimum(0)
sliderF.setMaximum(100)
sliderF.setValue(0)
sliderF.valueChanged.connect(updateForSpeed)
sliderF.setStyleSheet("QSlider::handle:vertical {background-color: rgb(0,255,0);}")
leftLayout.addWidget(sliderF)

sliderLabelR=QLabel("Forward Speed")
sliderLabelR.setStyleSheet("font-size: 20px;")
leftLayout.addWidget(sliderLabelR)

sliderR=QSlider(Qt.Vertical)
sliderR.setMinimum(0)
sliderR.setMaximum(100)
sliderR.setValue(0)
sliderR.valueChanged.connect(updateRevSpeed)
sliderR.setStyleSheet("QSlider::handle:vertical {background-color: rgb(0,0,255);}")
leftLayout.addWidget(sliderR)

greenButton=QPushButton("GO")
greenButton.setStyleSheet("background-color: rgb(0,255,0); border-radius: 50px; min-height: 100px; font-size: 20px; color: black;")
blueButton=QPushButton("REVERSE")
blueButton.setStyleSheet("background-color: rgb(0,0,255); border-radius: 50px; min-height: 100px; font-size: 20px; color: white;")
redButton=QPushButton("STOP")
redButton.setStyleSheet("background-color: rgb(255,0,0); border-radius: 50px; min-height: 100px; font-size: 20px; color: black;")

greenButton.clicked.connect(motorGo)
rightLayout.addWidget(greenButton)

blueButton.clicked.connect(motorRev)
rightLayout.addWidget(blueButton)

redButton.clicked.connect(motorStop)
rightLayout.addWidget(redButton)

timer =QTimer()
timer.timeout.connect(updateMotor)
timer.start(200)

mainLayout.addLayout(leftLayout)
mainLayout.addLayout(rightLayout)
window.setLayout(mainLayout)
window.show()
sys.exit(app.exec_())

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import socket

import time

from PyQt5.QtWidgets import *

from PyQt5.QtCore import *

import sys

speedF=0

speedR=0

motorStatus='O'

# Set up UDP client

client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

client_socket.settimeout(1)

server_address = ('192.168.88.19', 12345) # Adjust IP address and port as needed

app=QApplication(sys.argv)

window=QWidget()

window.setWindowTitle("Big Boss Motor Controller")

window.setGeometry(100,100,800,600)

mainLayout=QHBoxLayout(window)

leftLayout=QVBoxLayout()

rightLayout=QVBoxLayout()

def updateMotor():

global motorStatus,speedF,speedR

try:

print(motorStatus)

if motorStatus=='F':

cmd=motorStatus+','+str(speedF)

if motorStatus=='R':

cmd=motorStatus+','+str(speedR)

if motorStatus=='O':

cmd=motorStatus+','+str(0)

client_socket.sendto(cmd.encode(), server_address)

data, addr = client_socket.recvfrom(1024)

print('Received data:', data.decode())

except:

print("Server Did Not Respond, Try Again")

def updateForSpeed(value):

global speedF

speedF=value

print(speedF)

def updateRevSpeed(value):

global speedR

speedR=value

print(speedR)

def motorGo():

global motorStatus

motorStatus = 'F'

print("GO")

def motorRev():

global motorStatus

motorStatus = 'R'

print("REV")

def motorStop():

global motorStatus

motorStatus = 'O'

print("STOP")

sliderLabelF=QLabel("Forward Speed")

sliderLabelF.setStyleSheet("font-size: 20px;")

leftLayout.addWidget(sliderLabelF)

sliderF=QSlider(Qt.Vertical)

sliderF.setMinimum(0)

sliderF.setMaximum(100)

sliderF.setValue(0)

sliderF.valueChanged.connect(updateForSpeed)

sliderF.setStyleSheet("QSlider::handle:vertical {background-color: rgb(0,255,0);}")

leftLayout.addWidget(sliderF)

sliderLabelR=QLabel("Forward Speed")

sliderLabelR.setStyleSheet("font-size: 20px;")

leftLayout.addWidget(sliderLabelR)

sliderR=QSlider(Qt.Vertical)

sliderR.setMinimum(0)

sliderR.setMaximum(100)

sliderR.setValue(0)

sliderR.valueChanged.connect(updateRevSpeed)

sliderR.setStyleSheet("QSlider::handle:vertical {background-color: rgb(0,0,255);}")

leftLayout.addWidget(sliderR)

greenButton=QPushButton("GO")

greenButton.setStyleSheet("background-color: rgb(0,255,0); border-radius: 50px; min-height: 100px; font-size: 20px; color: black;")

blueButton=QPushButton("REVERSE")

blueButton.setStyleSheet("background-color: rgb(0,0,255); border-radius: 50px; min-height: 100px; font-size: 20px; color: white;")

redButton=QPushButton("STOP")

redButton.setStyleSheet("background-color: rgb(255,0,0); border-radius: 50px; min-height: 100px; font-size: 20px; color: black;")

greenButton.clicked.connect(motorGo)

rightLayout.addWidget(greenButton)

blueButton.clicked.connect(motorRev)

rightLayout.addWidget(blueButton)

redButton.clicked.connect(motorStop)

rightLayout.addWidget(redButton)

timer =QTimer()

timer.timeout.connect(updateMotor)

timer.start(200)

mainLayout.addLayout(leftLayout)

mainLayout.addLayout(rightLayout)

window.setLayout(mainLayout)

window.show()

sys.exit(app.exec_())

Python, Raspberry Pi Pico

Simple Client Server Project for the Raspberry Pi Pico W

February 25, 2025 admin

In this video lesson we demonstrate a simple client server project on the Raspberry Pi Pico W. The Pico is configures as the server, and your desktop pc or laptop is configures to be the client. You will be running python on your PC. The project requests the user on the PC to specify a desired color. The color is then sent to the Pico, the Server.

For this lesson we are not using the breadvolt power supply, but we will use it in future lessons. For this lesson, you do not need to attach it, and if you do attach it, leave it ‘off’.

Below is the schematic for the Server Side of the project:

LED and Buttons — Schematic for Circuit to Demonstrate a Client Server Example on Pi Pico

For your convenience, this is the code we developed in the video

import network
import usocket as socket
import secrets
import time

greenLED=machine.Pin(18,machine.Pin.OUT)
yellowLED=machine.Pin(19,machine.Pin.OUT)
redLED=machine.Pin(20,machine.Pin.OUT)
# Set up WiFi connection
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
print(secrets.SSID,secrets.PASSWORD)
wlan.connect(secrets.SSID,secrets.PASSWORD)

# Wait for connection
while not wlan.isconnected():
    time.sleep(1)
print("Connection Completed")
print('WiFi connected')
print(wlan.ifconfig())

# Set up UDP server
server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.bind((wlan.ifconfig()[0], 12345))
print("Server is Up and Listening")
print(wlan.ifconfig()[0])

while True:
    print('Waiting for a request from the client...')
    # Receive request from client
    color, client_address = server_socket.recvfrom(1024)
    color=color.decode()
    print("Client Request:",color)
    print("FROM CLIENT",client_address)
    
    if (color=="green"):
        greenLED.on()
        yellowLED.off()
        redLED.off()
    if (color=="yellow"):
        greenLED.off()
        yellowLED.on()
        redLED.off()
    if (color=="red"):
        greenLED.off()
        yellowLED.off()
        redLED.on()
    if (color=="off"):
        greenLED.off()
        yellowLED.off()
        redLED.off()
    
    # Send data to client
    data="LED "+color+" executed"
    server_socket.sendto(data.encode(), client_address)
    print(f'Sent data to {client_address}')
    
    # Optional: Pause for a short period to prevent overwhelming the client
    time.sleep(1)

import network

import usocket as socket

import secrets

import time

greenLED=machine.Pin(18,machine.Pin.OUT)

yellowLED=machine.Pin(19,machine.Pin.OUT)

redLED=machine.Pin(20,machine.Pin.OUT)

# Set up WiFi connection

wlan = network.WLAN(network.STA_IF)

wlan.active(True)

print(secrets.SSID,secrets.PASSWORD)

wlan.connect(secrets.SSID,secrets.PASSWORD)

# Wait for connection

while not wlan.isconnected():

time.sleep(1)

print("Connection Completed")

print('WiFi connected')

print(wlan.ifconfig())

# Set up UDP server

server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

server_socket.bind((wlan.ifconfig()[0], 12345))

print("Server is Up and Listening")

print(wlan.ifconfig()[0])

while True:

print('Waiting for a request from the client...')

# Receive request from client

color, client_address = server_socket.recvfrom(1024)

color=color.decode()

print("Client Request:",color)

print("FROM CLIENT",client_address)

if (color=="green"):

greenLED.on()

yellowLED.off()

redLED.off()

if (color=="yellow"):

greenLED.off()

yellowLED.on()

redLED.off()

if (color=="red"):

greenLED.off()

yellowLED.off()

redLED.on()

if (color=="off"):

greenLED.off()

yellowLED.off()

redLED.off()

# Send data to client

data="LED "+color+" executed"

server_socket.sendto(data.encode(), client_address)

print(f'Sent data to {client_address}')

# Optional: Pause for a short period to prevent overwhelming the client

time.sleep(1)

Remember you must create a secrets.py file, and save it on the Pi Pico in the lib folder. You need to specify YOUR WiFi name and password in the file.

SSID="YOUR WIFI NAME"
PASSWORD="YOUR WIFI PASSWORD"

1 2	SSID="YOUR WIFI NAME" PASSWORD="YOUR WIFI PASSWORD"

And finally, here is the code to run on the client side on your PC

import socket
import time

# Set up UDP client
client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_address = ('192.168.88.71', 12345)  # Adjust IP address and port as needed

while True:
    # Send request to the server
    myColor=input("Please Input Your Color (Green, Yellow, Red, Off )")
    myColor=myColor.lower()
    client_socket.sendto(myColor.encode(), server_address)
    
    # Receive data from the server
    data, addr = client_socket.recvfrom(1024)
    print('Received data:', data.decode())

import socket

import time

# Set up UDP client

client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

server_address = ('192.168.88.71', 12345) # Adjust IP address and port as needed

while True:

# Send request to the server

myColor=input("Please Input Your Color (Green, Yellow, Red, Off )")

myColor=myColor.lower()

client_socket.sendto(myColor.encode(), server_address)

# Receive data from the server

data, addr = client_socket.recvfrom(1024)

print('Received data:', data.decode())

Python, Raspberry Pi Pico

Sending Data Over WiFi Between Raspberry Pi Pico W and Your PC

February 18, 2025 admin

In this video lesson we show how we can send and receive data between the Raspberry Pi Pico W, and your PC. We will be running python on the PC, and we will exchange data using the UDP protocol. UDP is simple, and a very reliable way to send data packets back and forth. In this example, we will be demonstrating a simple Client Server relationship between the Pi Pico and PC using UDP over WiFi.

For your convenience, this is the “Server” software you will run on the Pi Pico.

import network
import usocket as socket
import secrets
import time

wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(secrets.SSID,secrets.PASSWORD)

# Wait for connection
while not wlan.isconnected():
    time.sleep(1)
print("Connection Completed")
print('WiFi connected')
print(wlan.ifconfig())

# Set up UDP server
server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.bind((wlan.ifconfig()[0], 12345))
print("Server is Up and Listening")
print(wlan.ifconfig()[0])

while True:
    print('Waiting for a request from the client...')
    # Receive request from client
    request, client_address = server_socket.recvfrom(1024)
    print("Client Request:",request.decode())
    print("FROM CLIENT",client_address)
    
    # String to send
    data = "225,128,64"
    
    # Send data to client
    server_socket.sendto(data.encode(), client_address)
    print(f'Sent data to {client_address}')
    
    # Optional: Pause for a short period to prevent overwhelming the client
    time.sleep(1)

import network

import usocket as socket

import secrets

import time

wlan = network.WLAN(network.STA_IF)

wlan.active(True)

wlan.connect(secrets.SSID,secrets.PASSWORD)

# Wait for connection

while not wlan.isconnected():

time.sleep(1)

print("Connection Completed")

print('WiFi connected')

print(wlan.ifconfig())

# Set up UDP server

server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

server_socket.bind((wlan.ifconfig()[0], 12345))

print("Server is Up and Listening")

print(wlan.ifconfig()[0])

while True:

print('Waiting for a request from the client...')

# Receive request from client

request, client_address = server_socket.recvfrom(1024)

print("Client Request:",request.decode())

print("FROM CLIENT",client_address)

# String to send

data = "225,128,64"

# Send data to client

server_socket.sendto(data.encode(), client_address)

print(f'Sent data to {client_address}')

# Optional: Pause for a short period to prevent overwhelming the client

time.sleep(1)

Notice that the above code wants to load a “secrets” file that contain your WiFi name, and password

You should edit the code below with your WiFi username and your password, and then save the file in the Pi Pico lib folder, with the name secrets.py (don’t forget the .py)

SSID="YOUR WIFI NAME"
PASSWORD="YOUR WIFI PASSWORD"

1 2	SSID="YOUR WIFI NAME" PASSWORD="YOUR WIFI PASSWORD"

Now, on the PC side, you will run your client, which will be run in Python. Here is the client software:

import socket
import time

# Set up UDP client
client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_address = ('192.168.88.71', 12345)  # Adjust IP address and port as needed

while True:
    # Send request to the server
    request_message = "SEND DATA"
    client_socket.sendto(request_message.encode(), server_address)
    
    # Receive data from the server
    data, addr = client_socket.recvfrom(1024)
    print('Received data:', data.decode())
    
    # Send acknowledgment back to server
    #ack_message = "Data received successfully"
    #client_socket.sendto(ack_message.encode(), addr)
    
    # Wait for 10 seconds before next request
    time.sleep(10)

import socket

import time

# Set up UDP client

client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

server_address = ('192.168.88.71', 12345) # Adjust IP address and port as needed

while True:

# Send request to the server

request_message = "SEND DATA"

client_socket.sendto(request_message.encode(), server_address)

# Receive data from the server

data, addr = client_socket.recvfrom(1024)

print('Received data:', data.decode())

# Send acknowledgment back to server

#ack_message = "Data received successfully"

#client_socket.sendto(ack_message.encode(), addr)

# Wait for 10 seconds before next request

time.sleep(10)

Technology Tutorials

Tag Archives: UDP

Parsing Comma Delimited Data Strings in Arduino

Create a Simple Client Server Connection Over WiFi to Connect Arduino to Python on the PC

Remotely Control a DC Motor Over WiFi With Raspberry Pi Pico W

Simple Client Server Project for the Raspberry Pi Pico W

Sending Data Over WiFi Between Raspberry Pi Pico W and Your PC

Making The World a Better Place One High Tech Project at a Time. Enjoy!