All posts by admin

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)

Arduino

Measure Altitude with an Arduino Project

February 13, 2025 admin

In this video lesson I show you how you can create a project for measuring altitude using an arduino and a BMP180 Pressure Sensor. We go through the physics, math, circuit and coding to make this project work. For our example, we are using a GY-87 module, which has a BMP180 sensor on it. If you are using a BMP180 sensor directly, it should work the same. For your convenience, this is the circuit schematic we will be using:

For your convenience, the code we developed in the video lesson above is included below. Enjoy!

#include <Adafruit_BMP085.h>

Adafruit_BMP085 BP;
bool BMPconnected;
bool haveBase = false;

float basePressure;
float Height = 0;
float HeightNow=0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  BMPconnected = BP.begin();
  if (BMPconnected == true) {
    Serial.println("BMP180 Found and Connected.");
  }
  if (BMPconnected == false) {
    Serial.println("BMP180 Not Found! Check Connections.");
  }
}

void loop() {
  // put your main code here, to run repeatedly:
  if (haveBase==false){
    Serial.println("Place Device at Base, Enter Go:");
    while (Serial.available()==0){

    }
    basePressure=BP.readPressure();
    haveBase = true;
  }
  HeightNow = findHeight(basePressure);
  Height= .95*Height + .05*HeightNow;
  Serial.print(5);
  Serial.print(",");
  Serial.print(-5);
  Serial.print(",");
  Serial.print(HeightNow);
  Serial.print(",");
  Serial.println(Height);

  delay(10);

}

float findHeight(float p0){
  float d;
  float T0 =288.15;
  float L =.0065; 
  float R = 8.3144598;
  float M = .0289644;
  float g = 9.8;
  float pH;
  pH=BP.readPressure();
  float c=R*L/(M*g);
  d = T0/L*(1 - pow((pH/p0), c ));
  d = d * 3.28084;
  return d;
}

#include <Adafruit_BMP085.h>

Adafruit_BMP085 BP;

bool BMPconnected;

bool haveBase = false;

float basePressure;

float Height = 0;

float HeightNow=0;

void setup() {

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

Serial.begin(9600);

BMPconnected = BP.begin();

if (BMPconnected == true) {

Serial.println("BMP180 Found and Connected.");

}

if (BMPconnected == false) {

Serial.println("BMP180 Not Found! Check Connections.");

}

void loop() {

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

if (haveBase==false){

Serial.println("Place Device at Base, Enter Go:");

while (Serial.available()==0){

}

basePressure=BP.readPressure();

haveBase = true;

}

HeightNow = findHeight(basePressure);

Height= .95*Height + .05*HeightNow;

Serial.print(5);

Serial.print(",");

Serial.print(-5);

Serial.print(",");

Serial.print(HeightNow);

Serial.print(",");

Serial.println(Height);

delay(10);

}

float findHeight(float p0){

float d;

float T0 =288.15;

float L =.0065;

float R = 8.3144598;

float M = .0289644;

float g = 9.8;

float pH;

pH=BP.readPressure();

float c=R*L/(M*g);

d = T0/L*(1 - pow((pH/p0), c ));

d = d * 3.28084;

return d;

}

Raspberry Pi Pico

Portable Distance Measurement Project With HC-SR04 Ultrasonic Sensor

February 11, 2025 admin

In this video lesson we explore creating a portable distance measurement widget using the Raspberry Pi Pico W, the HC-SR04 Ultrasonic Sensor, and the SSD1306 OLED display.

The schematic we use for this project is as follows:

In this work, we use the State Machines on the Pi Pico to ensure precise timing. Below, we include the code developed in the lesson above:

import rp2
from machine import Pin,I2C  #***************
import time
from ssd1306 import SSD1306_I2C  #**************

i2c2=I2C(1,sda=Pin(2), scl=Pin(3), freq=400000)
dsp=SSD1306_I2C(128,64,i2c2)

@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW)
def pulse_program():
    wrap_target()
    pull(block)
    mov(x,osr)
    set(pins,1)[31-1]
    set(pins,0)
    wait(1,pin,0)
    label("land")
    in_(pins,1) # 1 Cycle
    mov(y,isr)  # 1 Cycle
    jmp(not_y,"moveOn") # 1 Cycle
    jmp(x_dec,"land")  # 1 Cycle
    label("moveOn")
    mov(isr,invert(x))
    push()
    wrap()
triggerPin = Pin(18,Pin.OUT)
echoPin = Pin(19, Pin.IN)
sm=rp2.StateMachine(0,pulse_program, freq=1000000, set_base=triggerPin,in_base=echoPin)
sm.active(1)
while True:
    sm.put(0xFFFFFFFF)
    print("Pulse Launched")
    clockCycles=(sm.get())*4/2
    distance=clockCycles*.0342
    print("Distance to Target: ",distance)
    dsp.text("Distance: "+str(distance),0,16)
    dsp.show()
    dsp.fill(0)
    time.sleep(.25)

import rp2

from machine import Pin,I2C #***************

import time

from ssd1306 import SSD1306_I2C #**************

i2c2=I2C(1,sda=Pin(2), scl=Pin(3), freq=400000)

dsp=SSD1306_I2C(128,64,i2c2)

@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW)

def pulse_program():

wrap_target()

pull(block)

mov(x,osr)

set(pins,1)[31-1]

set(pins,0)

wait(1,pin,0)

label("land")

in_(pins,1) # 1 Cycle

mov(y,isr) # 1 Cycle

jmp(not_y,"moveOn") # 1 Cycle

jmp(x_dec,"land") # 1 Cycle

label("moveOn")

mov(isr,invert(x))

push()

wrap()

triggerPin = Pin(18,Pin.OUT)

echoPin = Pin(19, Pin.IN)

sm=rp2.StateMachine(0,pulse_program, freq=1000000, set_base=triggerPin,in_base=echoPin)

sm.active(1)

while True:

sm.put(0xFFFFFFFF)

print("Pulse Launched")

clockCycles=(sm.get())*4/2

distance=clockCycles*.0342

print("Distance to Target: ",distance)

dsp.text("Distance: "+str(distance),0,16)

dsp.show()

dsp.fill(0)

time.sleep(.25)

Arduino

Measure Air Pressure with the Arduino and BMP180 Pressure Sensor

February 6, 2025 admin

In this video lesson we explain how to use the BMP180 to measure barometric pressure and temperature. We explain basic concepts of what pressure is, and we show how the BMP180 measures pressure. The circuit schematic we use is shown here:

For your convenience, this is the code we developed in the video for measuring Temperature and Barometric Pressure.

#include <Adafruit_BMP085.h>
Adafruit_BMP085 BP;

float Pressure;
float tempC;
bool BMPconnected;
void setup() {
  Serial.begin(9600);
  BMPconnected = BP.begin();
  if (BMPconnected == true) {
    Serial.println("BMP180 Found and Connected.");
  }
  if (BMPconnected == false) {
    Serial.println("BMP180 Not Found. Check Connections");
  }
}
void loop() {
  tempC = BP.readTemperature();
  Pressure = BP.readPressure();
  Serial.println("READINGS ------------");
  Serial.print("Temperature = ");
  Serial.print(BP.readTemperature());
  Serial.println(" *C");

  Serial.print("Pressure = ");
  Serial.print(Pressure);
  Serial.println(" Pascals");
  Serial.println("");

  delay(1000);
}

#include <Adafruit_BMP085.h>

Adafruit_BMP085 BP;

float Pressure;

float tempC;

bool BMPconnected;

void setup() {

Serial.begin(9600);

BMPconnected = BP.begin();

if (BMPconnected == true) {

Serial.println("BMP180 Found and Connected.");

}

if (BMPconnected == false) {

Serial.println("BMP180 Not Found. Check Connections");

}

void loop() {

tempC = BP.readTemperature();

Pressure = BP.readPressure();

Serial.println("READINGS ------------");

Serial.print("Temperature = ");

Serial.print(BP.readTemperature());

Serial.println(" *C");

Serial.print("Pressure = ");

Serial.print(Pressure);

Serial.println(" Pascals");

Serial.println("");

delay(1000);

}

Raspberry Pi Pico

Precision Ultrasonic Distance Measurement With PIO State Machines on Raspberry Pi Pico W

February 4, 2025 admin

In this video lesson we will show you how to get precise distance measurements with the HC-SR04 Ultrasonic sensor. We show how measurement stability and accuracy can be improved by using the Raspberry Pi Pico PIO State Machines to trigger and monitor the sensor. For your convenience, the code is presented below.

import rp2
from machine import Pin
import time

@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW)
def pulse_program():
    wrap_target()
    pull(block)
    mov(x,osr)
    set(pins,1)[10-1]
    set(pins,0)
    wait(1,pin,0)
    label("land")
    mov(y,pins) # 1 clock cycle
    jmp(not_y,"moveOn") #1 clock cycle
    jmp(x_dec,"land") # 1 clock cycle
    label("moveOn")
    mov(isr,invert(x))
    push()
    wrap()
triggerPin = Pin(16,Pin.OUT)
echoPin = Pin(17, Pin.IN)
sm=rp2.StateMachine(0,pulse_program, freq=1000000, set_base=triggerPin,in_base=echoPin)
sm.active(1)
while True:
    sm.put(0xFFFFFFFF)
    print("Pulse Launched")
    clockCycles=sm.get()*3/2
    distance=clockCycles*.0342
    print("Distance to Target: ",distance)
    time.sleep(.25)

import rp2

from machine import Pin

import time

@rp2.asm_pio(set_init=rp2.PIO.OUT_LOW)

def pulse_program():

wrap_target()

pull(block)

mov(x,osr)

set(pins,1)[10-1]

set(pins,0)

wait(1,pin,0)

label("land")

mov(y,pins) # 1 clock cycle

jmp(not_y,"moveOn") #1 clock cycle

jmp(x_dec,"land") # 1 clock cycle

label("moveOn")

mov(isr,invert(x))

push()

wrap()

triggerPin = Pin(16,Pin.OUT)

echoPin = Pin(17, Pin.IN)

sm=rp2.StateMachine(0,pulse_program, freq=1000000, set_base=triggerPin,in_base=echoPin)

sm.active(1)

while True:

sm.put(0xFFFFFFFF)

print("Pulse Launched")

clockCycles=sm.get()*3/2

distance=clockCycles*.0342

print("Distance to Target: ",distance)

time.sleep(.25)

Technology Tutorials

All posts by admin

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

Measure Altitude with an Arduino Project

Portable Distance Measurement Project With HC-SR04 Ultrasonic Sensor

Measure Air Pressure with the Arduino and BMP180 Pressure Sensor

Precision Ultrasonic Distance Measurement With PIO State Machines on Raspberry Pi Pico W

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