Going throughthe videos/readings
**#1 Pseudo – analog output
**practicing loop() function and understanding forloop.
int pwmVal;
void setup() {
pinMode(11, OUTPUT);
}
void loop() {
for(int pwmVal=0; pwmVal<=255; pwmVal++){
analogWrite(11,pwmVal);
delay(20);
}
}it took a while to fully understand this code , especially the for loop. #2 servo motor
Servo Control using Pulse Width Modulation
include <Servo.h>
Servo myServo;
void setup() {
myServo.attach(9);
}
void loop(){
int sensor = analogRead(A0);
int angle = map(sensor, 0, 1023, 0, 180);
myServo.write(angle);
delay(20); }#3 speaker tone output https://youtu.be/8PVqjp8jmf4
void setup(){
Serial.begin(9600);
}
void loop(){
int sensor = analogRead(A0);
int frequency = map(sensor, 0, 1023, 100, 880);
tone(9, frequency);
delay (50);
}at first I didn’t put Serial.begin(9600); in the setup() so the sound was not gradually changing.
I guess you have to put Serial.begin(9600); in the setup() in order to deal with the analog value . (but in the video they didnt have Serial.begin(9600);== but it still worked so I’m confused.
void setup(){ //pin the LED output to D9
pinMode(9, OUTPUT);
}
void loop(){
//potentiometer output is plugged into A0 so that it can read analog input
int onTime = analogRead(A0); //when LEDis turned on
digitalWrite(9,HIGH); //duration of the LED being on
delayMicroseconds(onTime);
digitalWrite(9,LOW);//duration of the LED being off
delayMicroseconds(1023 - onTime);
}Lab Activity for Wk3
**#1 Check the sensor input range
**
void setup() { Serial.begin(9600); // initialize serial communications
}
void loop() {
int analogValue = analogRead(A0);
// read the analog input
Serial.println(analogValue);
// print it
}take away point :
the Arduino NANO 3.3IoT that we have cannot get voltage from 5V pin.
I had the + bus on the side wired from 5V and it didn’t work at first. but when I changed the output wire connected from 5V to 3.3V, it worked.
#2 Check that the Speaker Works
void setup() {
// nothing to do here
} void loop() {
// play the tone for 1 second:
tone(8, 440,1000);// do nothing else for the one second you're playing:
delay(1000);
}the code above will make the sound continuously, to make it sound like a beep-beep pattern I made the duration of the sound shorter than the delay duration.
void loop() {
tone(8, 440, 700); // 0.7 s on
delay(1000); // 1.0 s total cycle → ~0.3 s off
}
void loop() {
tone(8, 440); // start
delay(700); // on
noTone(8); // stop
delay(300); // off
}#3 Play Tones https://youtu.be/TQ9j_0GM8xs
void setup() {
// nothing to do here
Serial.begin(9600);
} void loop() {// get a sensor reading:
int sensorReading = analogRead(A0);
Serial.println(sensorReading);// map the results from the sensor reading's range // to the desired pitch range: float frequency
map(sensorReading,10, 900, 100, 1000); // change the pitch, play for 10 ms:
tone(8, frequency, 10);
delay(10);
}ㄴ I added the highlighted lines above from the given code to find out the range of my FSR values and adjust the mappping.
“If you want to know how to generate a tone without the tone() command, here’s the basic algorithm to play one wavelength:”
void makeTone(float frequency) {
// set the period in microseconds:
int period = (1 / frequency) * 1000000; // turn the speaker on:
digitalWrite(speakerPin, HIGH); // delay half the period:
delayMicroseconds(period / 2); // turn the speaker off:
digitalWrite(speakerPin, LOW); // delay half the period:
delayMicroseconds(period / 2); }my take away from this code above :
frequency = cycle per second (Hz)
period = 1 / frequency
multiplying by 1,000,000 converts seconds into microseconds
int speakerPin = 8;
float f = 0;
void setup() {// nothing to do here
Serial.begin(9600);
pinMode(speakerPin, OUTPUT);// pinMode(speakerPin, HIGH);
} void loop() {
int millisec = millis();
int seconds = millisec / 1000;
if (seconds % 5 == 0) {
f = random(260.00, 1000.00);
}
Serial.println(f);
makeTone(f); // tone(speakerPin, f, 1000);
}
void makeTone(float frequency) {
// set the period in microseconds:
int period = (1 / frequency) * 1000000;
// turn the speaker on:,
digitalWrite(speakerPin, HIGH);
// delay half the period:
delayMicroseconds(period / 2); // turn the speaker off:
digitalWrite(speakerPin, LOW); // delay half the period:
delayMicroseconds(period / 2); }**#4 Play it Loud
**
this excercise was confusing for me to understand the electricity flow of this circuit.
#5 Musical Instrument
https://www.youtube.com/shorts/Ak8WeItg8K8
include "pitches.h"
const int threshold = 40;
// minimum reading of the sensors that generates a note
const int speakerPin = 8; // pin number for the speaker
const int noteDuration = 20; // play notes for 20 ms //notes to play, corresponding to the 3 sensors:
int notes[] = {
NOTE_A4, NOTE_B4,NOTE_G4 };
void setup() {
pinMode(speakerPin, OUTPUT);
}
void loop() {
for (int thisSensor = 0; thisSensor < 3; thisSensor++)
}
int sensorReading = analogRead(thisSensor);
Serial.println(sensorReading);// if the sensor is pressed hard enough:
if (sensorReading > threshold) {
// play the note corresponding to this sensor:
tone(speakerPin, notes[thisSensor], noteDuration); delay(noteDuration);
}
}
}==NOTE_A4, NOTE_B4,NOTE_G4
==ㄴ at first it included NOTE_C3 but it wasnt playing the note. and Arjun guess was right that NOTE_C3 have low frequency that the speaker couldn’t handle. so we changed it to NOTE_G4 and now it works.
==Serial.println(sensorReading);
ㄴ at first I had the threshold set to 10 which was too low to get rid of all the noise when not pressing any sonsors. So we added this Serial.println(sensorReading);== to figure out the maximum value it gives when not pressing any sensor. Then we adjusted the value to 40 and that’s how we removed the noise from the speaker.
==for (int thisSensor = 0; thisSensor < 3; thisSensor++) {
// get a sensor reading:
int sensorReading = analogRead(thisSensor);==
ㄴ Arjun helped me understand how a for loop works. now I understand fully how this code works.
