Category Archives: Raspberry Pi Pico

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)

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)

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)

Raspberry Pi Pico

Measure Distance Using the HC-SR04 Ultrasonic Sensor on the Raspberry Pi Pico

January 28, 2025 admin

In this Video Lesson I will teach you how to use echolocation to measure distances. We will use the HC-SR04 Ultrasonic Sensor, and will use the Raspberry Pi Pico W. We will explain how echolocation works, and show you how the sensor works. We will do the math, and then create the code for making measurements.

import machine
import time

TRIG_PIN = 16
ECHO_PIN = 17

TRIG = machine.Pin(TRIG_PIN,machine.Pin.OUT)
ECHO = machine.Pin(ECHO_PIN,machine.Pin.IN)

def distance():
    TRIG.low()
    time.sleep_us(2)
    TRIG.high()
    time.sleep_us(10)
    TRIG.low()
    while (ECHO.value()==0):
        pass
    time1=time.ticks_us()
    while (ECHO.value()==1):
        pass
    time2=time.ticks_us()
    pingTime=time.ticks_diff(time2,time1)/2
    d=.0343*pingTime
    return d
while True:
    dist=distance()
    print("Distance to Target: ",dist," cm")
    time.sleep_ms(250)

import machine

import time

TRIG_PIN = 16

ECHO_PIN = 17

TRIG = machine.Pin(TRIG_PIN,machine.Pin.OUT)

ECHO = machine.Pin(ECHO_PIN,machine.Pin.IN)

def distance():

TRIG.low()

time.sleep_us(2)

TRIG.high()

time.sleep_us(10)

TRIG.low()

while (ECHO.value()==0):

pass

time1=time.ticks_us()

while (ECHO.value()==1):

pass

time2=time.ticks_us()

pingTime=time.ticks_diff(time2,time1)/2

d=.0343*pingTime

return d

while True:

dist=distance()

print("Distance to Target: ",dist," cm")

time.sleep_ms(250)

Raspberry Pi Pico

Controlling NeoPixel Array on PIO State Machine on Raspberry Pi Pico

January 21, 2025 admin

In this video lesson we show how neopixels work at a fundamental level, and show how you can use the Raspberry Pi Pico State Machines to control the neoixels. Neopixels are an excellent example for showing the importance of the pico state machine. The neopixels demand precise timing and sequence of bits to operate properly, and that precision can not be achieved in python. The video explains how the State Machines can be programmed to control the neopixels.

For your convenience, the code is included below.

import rp2
from machine import Pin
import time
@rp2.asm_pio(sideset_init=rp2.PIO.OUT_HIGH,
             out_shiftdir=rp2.PIO.SHIFT_LEFT,
             autopull=True,
             pull_thresh=24)
def ws2812():
    wrap_target()
    label("bitloop")
    out(x,1).side(0)
    jmp(not_x,"do_zero").side(1)
    nop().side(1)[5-1]
    nop().side(0)[2-1]
    jmp("bitloop").side(0)
    label("do_zero")
    nop().side(1)[2-1]
    jmp("bitloop").side(0)[6-1]
    wrap()
sm=rp2.StateMachine(0,ws2812,freq=8000000,sideset_base=Pin(0))
sm.active(1)

def write_neopixel(colors):
    for color in colors:
        grb=color[1]<<16 | color[0]<<8 | color[2]
        sm.put(grb,8)
        
    
NUM_LEDS =8
myColor=[0]*NUM_LEDS
myColor=[[100,0,0],
         [0,100,0],
         [0,0,100],
         [0,100,100],
         [100,0,100],
         [100,100,0],
         [200,100,0],
         [255,255,255]]
write_neopixel(myColor)

import rp2

from machine import Pin

import time

@rp2.asm_pio(sideset_init=rp2.PIO.OUT_HIGH,

out_shiftdir=rp2.PIO.SHIFT_LEFT,

autopull=True,

pull_thresh=24)

def ws2812():

wrap_target()

label("bitloop")

out(x,1).side(0)

jmp(not_x,"do_zero").side(1)

nop().side(1)[5-1]

nop().side(0)[2-1]

jmp("bitloop").side(0)

label("do_zero")

nop().side(1)[2-1]

jmp("bitloop").side(0)[6-1]

wrap()

sm=rp2.StateMachine(0,ws2812,freq=8000000,sideset_base=Pin(0))

sm.active(1)

def write_neopixel(colors):

for color in colors:

grb=color[1]<<16 | color[0]<<8 | color[2]

sm.put(grb,8)

NUM_LEDS =8

myColor=[0]*NUM_LEDS

myColor=[[100,0,0],

[0,100,0],

[0,0,100],

[0,100,100],

[100,0,100],

[100,100,0],

[200,100,0],

[255,255,255]]

write_neopixel(myColor)

Technology Tutorials

Category Archives: Raspberry Pi Pico

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

Portable Distance Measurement Project With HC-SR04 Ultrasonic Sensor

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

Measure Distance Using the HC-SR04 Ultrasonic Sensor on the Raspberry Pi Pico

Controlling NeoPixel Array on PIO State Machine on Raspberry Pi Pico

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