Category Archives: Uncategorized

In this lesson we demonstrate using both cores on the Raspberry Pi Pico W. The program controls a servo from a push button. The servo is controlled on the second core by a thread, and the push button is monitored in the main program.

from machine import Pin
import time
import _thread
import SERVO

servoToggle=False
running = True
servoPin=17
myServo=SERVO.servo(servoPin)

redButPin=16
myRedButton=Pin(redButPin,Pin.IN,Pin.PULL_UP)
redButStateNow=1
redButStateOld=1

def othCore():
    global servoToggle
    global running
    servoState=0
    while running:
        if servoState==0 and servoToggle==True:
            for i in range(0,180,1):
                myServo.pos(i)
                time.sleep(.05)
            servoToggle=False
            servoState=180
        if servoState==180 and servoToggle==True:
            for i in range(180,0,-1):
                myServo.pos(i)
                time.sleep(.05)
            servoToggle=False
            servoState=0
    print("othCore Terminated")
    
_thread.start_new_thread(othCore,())
time.sleep(.25)
                

try:
    while True:
        redButStateNow=myRedButton.value()
        if redButStateNow==0 and redButStateOld==1:
            print("Toggle")
            servoToggle =True
        redButStateOld=redButStateNow
        time.sleep(.1)
except KeyboardInterrupt:
    print('Keyboard Interrupt')
    running=False
    time.sleep(.1)
    print("Program is Done")

from machine import Pin

import time

import _thread

import SERVO

servoToggle=False

running = True

servoPin=17

myServo=SERVO.servo(servoPin)

redButPin=16

myRedButton=Pin(redButPin,Pin.IN,Pin.PULL_UP)

redButStateNow=1

redButStateOld=1

def othCore():

global servoToggle

global running

servoState=0

while running:

if servoState==0 and servoToggle==True:

for i in range(0,180,1):

myServo.pos(i)

time.sleep(.05)

servoToggle=False

servoState=180

if servoState==180 and servoToggle==True:

for i in range(180,0,-1):

myServo.pos(i)

time.sleep(.05)

servoToggle=False

servoState=0

print("othCore Terminated")

_thread.start_new_thread(othCore,())

time.sleep(.25)

try:

while True:

redButStateNow=myRedButton.value()

if redButStateNow==0 and redButStateOld==1:

print("Toggle")

servoToggle =True

redButStateOld=redButStateNow

time.sleep(.1)

except KeyboardInterrupt:

print('Keyboard Interrupt')

running=False

time.sleep(.1)

print("Program is Done")

Uncategorized

Calibrating a Joystick on the Raspberry Pi Pico W in MicroPython

February 27, 2024 admin

In this lesson we show how to get intuitive calibrated results from a joystick, connected to a Raspberry Pi Pico W, using microPython. This lesson will make it easy to incorporate a joystick into Pico W projects.

For your convenience, the code we develop in the video above is included below.

import machine
import time
import math
hPin=27
vPin=26
hJoy= machine.ADC(hPin)
vJoy= machine.ADC(vPin)
while True:
    hVal=hJoy.read_u16()
    vVal=vJoy.read_u16()
    
    hCal=int(-.00306*hVal+100.766)
    vCal=int(.00306*vVal-100.766)
    
    mag=math.sqrt(hCal**2+vCal**2)
    if mag<=4:
        hCal=0
        vCal=0
    
    print(hCal,vCal)
    time.sleep_ms(200)

import machine

import time

import math

hPin=27

vPin=26

hJoy= machine.ADC(hPin)

vJoy= machine.ADC(vPin)

while True:

hVal=hJoy.read_u16()

vVal=vJoy.read_u16()

hCal=int(-.00306*hVal+100.766)

vCal=int(.00306*vVal-100.766)

mag=math.sqrt(hCal**2+vCal**2)

if mag<=4:

hCal=0

vCal=0

print(hCal,vCal)

time.sleep_ms(200)

Uncategorized

Measure Pitch and Roll with the MPU6050

November 30, 2023 admin

This is a simple example of how to measure Pitch and Roll using a 3-axis accelerometer as found on the MPU6050.

from imu import MPU6050
from machine import I2C,Pin
import math
import time

i2c=I2C(0, sda=Pin(16), scl=Pin(17), freq=400000)
mpu = MPU6050(i2c)

roll=0
pitch=0

while True:
    xAccel=mpu.accel.x
    yAccel=mpu.accel.y
    zAccel=mpu.accel.z
    pitch=math.atan(yAccel/zAccel)
    roll=math.atan(xAccel/zAccel)
    pitchDeg=pitch/(2*math.pi)*360
    rollDeg=roll/(2*math.pi)*360
    print('pitch: ',pitchDeg, 'roll: ',rollDeg)
    time.sleep(.05)

from imu import MPU6050

from machine import I2C,Pin

import math

import time

i2c=I2C(0, sda=Pin(16), scl=Pin(17), freq=400000)

mpu = MPU6050(i2c)

roll=0

pitch=0

while True:

xAccel=mpu.accel.x

yAccel=mpu.accel.y

zAccel=mpu.accel.z

pitch=math.atan(yAccel/zAccel)

roll=math.atan(xAccel/zAccel)

pitchDeg=pitch/(2*math.pi)*360

rollDeg=roll/(2*math.pi)*360

print('pitch: ',pitchDeg, 'roll: ',rollDeg)

time.sleep(.05)

Uncategorized

Using a MFRC522 RFID Module and Tag with the Raspberry Pi

June 19, 2023 admin

This lesson describes how to add RFID Tag capability to the Raspberry Pi. we will be using the MFRC522 RFID Module. The schematic below shows how to connect the device up to the Raspberry Pi through a standard breakout board.

RFID Schematic — Schematic for Connecting the MFRC522 RFID Module to the Raspberry Pi

Uncategorized

Calculating Frames Per Second (FPS) In OpenCV and Overlay on Frame

January 26, 2023 admin

In this lesson we show how to instrument our code to calculate the Frames Per Second (FPS) we are achieving with our camera and OpenCV. We show how to display the FPS as an overlay on our video frame.

import cv2
from picamera2 import Picamera2
import time
picam2 = Picamera2()
dispW=1280
dispH=720
picam2.preview_configuration.main.size = (dispW,dispH)
picam2.preview_configuration.main.format = "RGB888"
picam2.preview_configuration.controls.FrameRate=30
picam2.preview_configuration.align()
picam2.configure("preview")
picam2.start()
fps=0
pos=(30,60)
font=cv2.FONT_HERSHEY_SIMPLEX
height=1.5
weight=3
myColor=(0,0,255)
while True:
    tStart=time.time()
    im= picam2.capture_array()
    cv2.putText(im,str(int(fps))+' FPS',pos,font,height,myColor,weight)
    cv2.imshow("Camera", im)
    if cv2.waitKey(1)==ord('q'):
        break
    tEnd=time.time()
    loopTime=tEnd-tStart
    fps=.9*fps + .1*(1/loopTime)
cv2.destroyAllWindows()

import cv2

from picamera2 import Picamera2

import time

picam2 = Picamera2()

dispW=1280

dispH=720

picam2.preview_configuration.main.size = (dispW,dispH)

picam2.preview_configuration.main.format = "RGB888"

picam2.preview_configuration.controls.FrameRate=30

picam2.preview_configuration.align()

picam2.configure("preview")

picam2.start()

fps=0

pos=(30,60)

font=cv2.FONT_HERSHEY_SIMPLEX

height=1.5

weight=3

myColor=(0,0,255)

while True:

tStart=time.time()

im= picam2.capture_array()

cv2.putText(im,str(int(fps))+' FPS',pos,font,height,myColor,weight)

cv2.imshow("Camera", im)

if cv2.waitKey(1)==ord('q'):

break

tEnd=time.time()

loopTime=tEnd-tStart

fps=.9*fps + .1*(1/loopTime)

cv2.destroyAllWindows()

Technology Tutorials

Category Archives: Uncategorized

Cleanly Exiting Dual Core Program in MicroPython

Calibrating a Joystick on the Raspberry Pi Pico W in MicroPython

Measure Pitch and Roll with the MPU6050

Using a MFRC522 RFID Module and Tag with the Raspberry Pi

Calculating Frames Per Second (FPS) In OpenCV and Overlay on Frame

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