SunFounder Thales Kit, Manual

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SunFounder Thales Kit for Raspberry Pi Pico, Release 1.0
How it works?
To enable Serial Monitor, you need to start serial communication in
setup()
and set the datarate to 9600.
void setup () {
pinMode (ledPin, OUTPUT );
Serial . begin ( 9600 );
}
• Serial
In the loop function, the value of the potentiometer is read, then the value is mapped from 0-1023 to 0-255 and finally
the value after the mapping is used to control the brightness of the LED.
void loop () {
int sensorValue = analogRead (sensorPin);
Serial . println (sensorValue);
int brightness = map (sensorValue, 0 , 1023 , 0 , 255 );
analogWrite (ledPin, brightness);
}
• analogRead() is used to read the value of the sensorPin (potentiometer) and assigns it to the variable
sensorValue .
int sensorValue = analogRead (sensorPin);
• Print the value of SensorValue in Serial Monitor.
Serial . println (sensorValue);
• Here, the map(value, fromLow, fromHigh, toLow, toHigh) function is required as the potentiometer value read
is in the range 0-1023 and the value of a PWM pin is in the range 0-255. It is used to Re-maps a number from
one range to another. That is, a value of fromLow would get mapped to toLow, a value of fromHigh to toHigh,
values in-between to values in-between, etc.
int brightness = map (sensorValue, 0 , 1023 , 0 , 255 );
• Now we can use this value to control the brightness of the LED.
analogWrite (ledPin,brightness);
4.2.5 Measure Light Intensity
A photoresistor or photocell is a light-controlled variable resistor. The resistance of a photo resistor decreases with
increasing incident light intensity; in other words, it exhibits photo conductivity.
Therefore, we can use a photoresistor to measure light intensity, and then show it through 5 LEDs.
154 Chapter 4. For Arduino User