In this video lesson we show you how to measure temperature and humidity using the DHT11 sensor. For your convenience, we include the code below which we develop in the above video. Enjoy!

#include <DHT.h>
#define DHTPIN 11
#define DHTTYPE DHT11
DHT myDHT(DHTPIN,DHTTYPE);

int br=115200;
int setUpDelay=1000;
int measDelay=1000;

float tempC;
float tempF;
float hum;
float HIF;
float HIC;

String message;

void setup() {
  // put your setup code here, to run once:
Serial.begin(br);
myDHT.begin();
delay(setUpDelay);
}

void loop() {
  // put your main code here, to run repeatedly:
tempC=myDHT.readTemperature(false);
tempF=myDHT.readTemperature(true);
hum=myDHT.readHumidity();
if (isnan(tempC) || isnan(tempF) || isnan(hum)){
  Serial.println("Failed to Read Data on DHT11");
  return;
}
HIC=myDHT.computeHeatIndex(tempC,hum,false);
HIF=myDHT.computeHeatIndex(tempF,hum,true);
message="Temp: "+String(tempC)+" deg C "+String(tempF)+" deg F Humidity: "+String(hum)+" % Heat Index: "+String(HIC)+" deg C "+String(HIF)+" deg F.";
Serial.println(message);
// Serial.print("Temp: ");
// Serial.print(tempC);
// Serial.print(" deg C ");
// Serial.print(tempF);
// Serial.print(" deg F ");
// Serial.print("Humidity: ");
// Serial.print(hum);
// Serial.print(" % ");
// Serial.print("Heat Index: ");
// Serial.print(HIC);
// Serial.print(" deg C ");
// Serial.print(HIF);
// Serial.println(" deg F ");


delay(measDelay);
}

#include <DHT.h>

#define DHTPIN 11

#define DHTTYPE DHT11

DHT myDHT(DHTPIN,DHTTYPE);

int br=115200;

int setUpDelay=1000;

int measDelay=1000;

float tempC;

float tempF;

float hum;

float HIF;

float HIC;

String message;

void setup() {

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

Serial.begin(br);

myDHT.begin();

delay(setUpDelay);

}

void loop() {

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

tempC=myDHT.readTemperature(false);

tempF=myDHT.readTemperature(true);

hum=myDHT.readHumidity();

if (isnan(tempC) || isnan(tempF) || isnan(hum)){

Serial.println("Failed to Read Data on DHT11");

return;

}

HIC=myDHT.computeHeatIndex(tempC,hum,false);

HIF=myDHT.computeHeatIndex(tempF,hum,true);

message="Temp: "+String(tempC)+" deg C "+String(tempF)+" deg F Humidity: "+String(hum)+" % Heat Index: "+String(HIC)+" deg C "+String(HIF)+" deg F.";

Serial.println(message);

// Serial.print("Temp: ");

// Serial.print(tempC);

// Serial.print(" deg C ");

// Serial.print(tempF);

// Serial.print(" deg F ");

// Serial.print("Humidity: ");

// Serial.print(hum);

// Serial.print(" % ");

// Serial.print("Heat Index: ");

// Serial.print(HIC);

// Serial.print(" deg C ");

// Serial.print(HIF);

// Serial.println(" deg F ");

delay(measDelay);

}

Arduino

Create a Bouncing Pixel on the Arduino Uno R4 WiFi LED Matrix

August 8, 2024 admin

In this video lesson we create a bouncing pixel on the Arduino Uno R4 LED Matrix. For your convenience we include the code developed in the video below.

#include "Arduino_LED_Matrix.h"
ArduinoLEDMatrix matrix;

int br=115200;
int dt=50;
int xPos=3;
int yPos=2;
int deltaX=1;
int deltaY=1;

int i;
int j;

byte frame[8][12];

void setup() {
  // put your setup code here, to run once:
Serial.begin(br);
matrix.begin();
}
void loop() {
  // put your main code here, to run repeatedly:
for ( i=0;i<=11;i=i+1){
  for (j=0;j<=7;j=j+1){
    frame[j][i]=0;
    if (i==xPos && j==yPos){
      frame[j][i]=1;
    }
  }
}
matrix.renderBitmap(frame,8,12);
if (xPos>=11 || xPos<=0){
  deltaX=-deltaX;
}
if (yPos>=7 || yPos<=0){
  deltaY=-deltaY;
}
xPos=xPos+deltaX;
yPos=yPos+deltaY;
delay(dt);
}

#include "Arduino_LED_Matrix.h"

ArduinoLEDMatrix matrix;

int br=115200;

int dt=50;

int xPos=3;

int yPos=2;

int deltaX=1;

int deltaY=1;

int i;

int j;

byte frame[8][12];

void setup() {

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

Serial.begin(br);

matrix.begin();

}

void loop() {

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

for ( i=0;i<=11;i=i+1){

for (j=0;j<=7;j=j+1){

frame[j][i]=0;

if (i==xPos && j==yPos){

frame[j][i]=1;

}

matrix.renderBitmap(frame,8,12);

if (xPos>=11 || xPos<=0){

deltaX=-deltaX;

}

if (yPos>=7 || yPos<=0){

deltaY=-deltaY;

}

xPos=xPos+deltaX;

yPos=yPos+deltaY;

delay(dt);

}

MicroPython, Raspberry Pi Pico

Control NeoPixel Array With Infrared IR Remote Control on Raspberry Pi Pico in MicroPython

July 17, 2024 admin

In this lesson we show how we can control the neoPixel array using an Infrared IR Remote Control on the Raspberry Pi Pico W in micropython. The video above explains things step-by-step. For your convenience, the code is included below. Enjoy!

import neopixel
from machine import Pin
import time

pixPin = 0
pixSize = 8
pix = neopixel.NeoPixel(Pin(pixPin), pixSize)

def getRGB(deg):
    m=1/60
    if deg>=0 and deg<60:
        R=1
        G=0
        B=m*deg
    if deg>=60 and deg<120:
        R=1-m*(deg-60)
        G=0
        B=1
    if deg>=120 and deg<180:
        R=0
        G=m*(deg-120)
        B=1
    if deg>=180 and deg<240:
        R=0
        G=1
        B=1-m*(deg-180)
    if deg>=240 and deg<300:
        R=m*(deg-240)
        G=1
        B=0
    if deg>=300 and deg<360:
        R=1
        G=1-m*(deg-300)
        B=0
    myColor=(int(R*255),int(G*255),int(B*255))
    return myColor

from ir_rx.print_error import print_error
from ir_rx.nec import NEC_8
import SERVO
IRdict ={69 : 'POWER', 70: 'MODE',71 : 'OFF',
         68: 'PLAY', 64 : 'BACK', 67 : 'FORWARD', 7: 'ENTER', 21: '-',
         9 : '+', 22 : 0,25 : 'LOOP', 13:'USD' ,
         12: 1, 24 : 2,94 : 3,
        8 :4, 28 : 5, 90 : 6,
        66 : 7, 82 : 8, 74 : 9}

newCommand=[]
beginRecord=False
cmdReady=False
angleString=''
newBit=""
irPin=17
cmd=0
myIR = Pin(irPin, Pin.IN)
def callback(IRbit, addr, ctrl):
    global newCommand
    global beginRecord
    global cmdReady
    global IRdict
    global cmd
    if IRbit==69:
        beginRecord=True
        newCommand=[]
        cmdReady=False
    if beginRecord==True and IRbit!=-1:
        newCommand.append(IRdict[IRbit])
    if IRbit==7:
        cmdReady=True
        cmd=newCommand[1]
        
IR = NEC_8(myIR, callback)  # Instantiate receiver
try:
    while True:
        if cmd==0:
            for i in range(0,8):
                pix[i]=[0,0,0]
            pix.write()
        if cmd==1:
            pix.fill([255,0,0])
            pix.write()
        if cmd==2:
            pix.fill([0,255,0])
            pix.write()
        if cmd==3:
            pix.fill([0,0,255])
            pix.write() 
        if cmd==4:
            for i in range(0,360,1):
                for j in range(0,8,1):
                    deg=i+(j)*45
                    if deg>=360:
                        deg=deg-360
                    color=getRGB(deg)
                    pix[j]=color
                    if cmd!=4:
                        break
                if cmd!=4:
                    break
                pix.write()
                time.sleep(.01)
        if cmd==5:
            for i in range(0,360,1):
                color=getRGB(i)
                pix.fill(color)
                pix.write()
                time.sleep(.01)
                if cmd!=5:
                    break
        if cmd==6:
            for i in range(1,8,1):
                pix.fill([255,0,0])
                pix[i]=[0,0,255]
                #pix[7-i]=green
                pix.write()
                time.sleep(.1)
                if cmd!=6:
                    break
            for i in range(6,-1,-1):
                pix.fill([255,0,0])
                pix[i]=[0,0,255]
                #pix[7-i]=green
                pix.write()
                time.sleep(.1)
                if cmd!=6:
                    break

except KeyboardInterrupt:
    IR.close()
    for i in range(0,8):
        pix[i]=[0,0,0]
        pix.write()
    print("Program Terminated")

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import neopixel

from machine import Pin

import time

pixPin = 0

pixSize = 8

pix = neopixel.NeoPixel(Pin(pixPin), pixSize)

def getRGB(deg):

m=1/60

if deg>=0 and deg<60:

R=1

G=0

B=m*deg

if deg>=60 and deg<120:

R=1-m*(deg-60)

G=0

B=1

if deg>=120 and deg<180:

R=0

G=m*(deg-120)

B=1

if deg>=180 and deg<240:

R=0

G=1

B=1-m*(deg-180)

if deg>=240 and deg<300:

R=m*(deg-240)

G=1

B=0

if deg>=300 and deg<360:

R=1

G=1-m*(deg-300)

B=0

myColor=(int(R*255),int(G*255),int(B*255))

return myColor

from ir_rx.print_error import print_error

from ir_rx.nec import NEC_8

import SERVO

IRdict ={69 : 'POWER', 70: 'MODE',71 : 'OFF',

68: 'PLAY', 64 : 'BACK', 67 : 'FORWARD', 7: 'ENTER', 21: '-',

9 : '+', 22 : 0,25 : 'LOOP', 13:'USD' ,

12: 1, 24 : 2,94 : 3,

8 :4, 28 : 5, 90 : 6,

66 : 7, 82 : 8, 74 : 9}

newCommand=[]

beginRecord=False

cmdReady=False

angleString=''

newBit=""

irPin=17

cmd=0

myIR = Pin(irPin, Pin.IN)

def callback(IRbit, addr, ctrl):

global newCommand

global beginRecord

global cmdReady

global IRdict

global cmd

if IRbit==69:

beginRecord=True

newCommand=[]

cmdReady=False

if beginRecord==True and IRbit!=-1:

newCommand.append(IRdict[IRbit])

if IRbit==7:

cmdReady=True

cmd=newCommand[1]

IR = NEC_8(myIR, callback) # Instantiate receiver

try:

while True:

if cmd==0:

for i in range(0,8):

pix[i]=[0,0,0]

pix.write()

if cmd==1:

pix.fill([255,0,0])

pix.write()

if cmd==2:

pix.fill([0,255,0])

pix.write()

if cmd==3:

pix.fill([0,0,255])

pix.write()

if cmd==4:

for i in range(0,360,1):

for j in range(0,8,1):

deg=i+(j)*45

if deg>=360:

deg=deg-360

color=getRGB(deg)

pix[j]=color

if cmd!=4:

break

if cmd!=4:

break

pix.write()

time.sleep(.01)

if cmd==5:

for i in range(0,360,1):

color=getRGB(i)

pix.fill(color)

pix.write()

time.sleep(.01)

if cmd!=5:

break

if cmd==6:

for i in range(1,8,1):

pix.fill([255,0,0])

pix[i]=[0,0,255]

#pix[7-i]=green

pix.write()

time.sleep(.1)

if cmd!=6:

break

for i in range(6,-1,-1):

pix.fill([255,0,0])

pix[i]=[0,0,255]

#pix[7-i]=green

pix.write()

time.sleep(.1)

if cmd!=6:

break

except KeyboardInterrupt:

IR.close()

for i in range(0,8):

pix[i]=[0,0,0]

pix.write()

print("Program Terminated")

Raspberry Pi Pico

Using an Infrared IR Remote Control in a Raspberry Pi Pico W Project

July 2, 2024 admin

In this lesson I show how to practically implement an Infrared IR sensor into a Raspberry Pi Pico project. For your convenience, the code developed in the video is included below.

import time
from machine import Pin, freq
from ir_rx.print_error import print_error
from ir_rx.nec import NEC_8
IRdict ={69 : 'POWER', 70: 'MODE',71 : 'OFF',
         68: 'PLAY', 64 : 'BACK', 67 : 'FORWARD', 7: 'ENTER', 21: '-',
         9 : '+', 22 : 0,25 : 'LOOP', 13:'USD' ,
         12: 1, 24 : 2,94 : 3,
        8 :4, 28 : 5, 90 : 6,
        66 : 7, 82 : 8, 74 : 9}
newCommand=[]
beginRecord=False
cmdReady=False
angleString=''
newBit=""
irPin=17
myIR = Pin(irPin, Pin.IN)
def callback(IRbit, addr, ctrl):
    global newCommand
    global beginRecord
    global cmdReady
    global IRdict
    if IRbit==69:
        beginRecord=True
        newCommand=[]
        cmdReady=False
    if beginRecord==True and IRbit!=-1:
        newCommand.append(IRdict[IRbit])
    if IRbit==7:
        cmdReady=True

IR = NEC_8(myIR, callback)  # Instantiate receiver

try:
    while True:
        if cmdReady==True:
            print(newCommand)
            cmdReady=False
except KeyboardInterrupt:
    IR.close()
    print("Program Terminated")

import time

from machine import Pin, freq

from ir_rx.print_error import print_error

from ir_rx.nec import NEC_8

IRdict ={69 : 'POWER', 70: 'MODE',71 : 'OFF',

68: 'PLAY', 64 : 'BACK', 67 : 'FORWARD', 7: 'ENTER', 21: '-',

9 : '+', 22 : 0,25 : 'LOOP', 13:'USD' ,

12: 1, 24 : 2,94 : 3,

8 :4, 28 : 5, 90 : 6,

66 : 7, 82 : 8, 74 : 9}

newCommand=[]

beginRecord=False

cmdReady=False

angleString=''

newBit=""

irPin=17

myIR = Pin(irPin, Pin.IN)

def callback(IRbit, addr, ctrl):

global newCommand

global beginRecord

global cmdReady

global IRdict

if IRbit==69:

beginRecord=True

newCommand=[]

cmdReady=False

if beginRecord==True and IRbit!=-1:

newCommand.append(IRdict[IRbit])

if IRbit==7:

cmdReady=True

IR = NEC_8(myIR, callback) # Instantiate receiver

try:

while True:

if cmdReady==True:

print(newCommand)

cmdReady=False

except KeyboardInterrupt:

IR.close()

print("Program Terminated")

Uncategorized

Cleanly Exiting Dual Core Program in MicroPython

May 21, 2024 admin

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")

Technology Tutorials

Using the Arduino Uno R4 Wifi to Measure Temperature and Humidity With the DHT11

Create a Bouncing Pixel on the Arduino Uno R4 WiFi LED Matrix

Control NeoPixel Array With Infrared IR Remote Control on Raspberry Pi Pico in MicroPython

Using an Infrared IR Remote Control in a Raspberry Pi Pico W Project

Cleanly Exiting Dual Core Program in MicroPython

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