Potentiometer

What is a potentiometer? The potentiometer is actually a variable resistor with three lead segments. The potentiometer is usually composed of a resistor body and a movable brush. When the brush moves along the resistor body, a resistance value or voltage that is related to the unique quantity is obtained at the output.

1 * microbit
1 * microbit expansion board
1 * usb cable
1 * Potentiomenter
-Several Jumper wires

The potentiometer used in this experiment:

Now connect the potentiometer to the micro:bit

Connection diagram：

Sample code：
Makecode:

MU Python:

  #-----------------------------------------------------------
  # File name   : Potentiomenter.py
  # Description : Read the value of the potentiometer.
  # Author      : jason
  # E-mail      : jason@adeept.com
  # Website     : www.adeept.com
  # Date        : 2018/12/20
  #-----------------------------------------------------------
  from microbit import *
 
  while True:
      # define potentiometer pin
      potentiometer_reading = pin0.read_analog()
      display.scroll(str(potentiometer_reading))
      sleep(1000)

When rotate the potentiometer, the analog value of it is displayed on the matrix LED.

Preparation
1 * Adeept Arduino UNO R3 Board
1 * Potentiometer Module
1 * USB Cable
1 * 3-Pin Wires

Connection diagram：

arduino code：

  /***********************************************************
  File name: PotentiometerModule.ino
  Description: Now, when you turning the shaft of the potentiometer,
               you will see the data in the serial monitor 
  Website: www.adeept.com
  E-mail: support@adeept.com
  Author: Tom
  Date: 2018/23/20 
  ***********************************************************/
  int potentiometerPin = 0;        // potentiometer wiper (middle terminal) connected to analog pin 0
  void setup() 
  {                
    pinMode(potentiometerPin, INPUT);
    Serial.begin(9600);           // opens serial port, sets data rate to 9600 bps
  }
  void loop() 
  {
   Serial.println(analogRead(0)); //send data to the serial monitor
   delay(50);                      // delay 0.05 s
  }

Select Arduino development board and COM port

Upload the code to Arduino

Then open the derail port：

Now when we rotate the potentiometer, we can see the data on the serial port.

1 * Raspberry Pi
1 * GPIO Extension Board
1 * 40-Pin GPIO Cable
1 * Breadboard
1 * ADC0832 Module
1 * Potentiometer Module
2 * 3-Pin Wires
1 * 5-Pin Wires

Step1: Connect the module according to the connection diagram below

C code:

    /*
   * Website     : www.adeept.com
   * E-mail      : support@adeept.com
   * Author      : Jason
   * Date        : 2018/12/20
   */
  #include <wiringPi.h>
  #include <stdio.h>
  
  typedef unsigned char uchar;
  typedef unsigned int  uint;
 
  #define     ADC_CS    0
  #define     ADC_DIO   1
  #define     ADC_CLK   2
  
  uchar get_ADC_Result(void)
  {
  	//10:CH0
  	//11:CH1
  	uchar i;
  	uchar dat1=0, dat2=0;
 
  	digitalWrite(ADC_CS, 0);
 
  	digitalWrite(ADC_CLK,0);
  	digitalWrite(ADC_DIO,1);	delayMicroseconds(2);
  	digitalWrite(ADC_CLK,1);	delayMicroseconds(2);
  	digitalWrite(ADC_CLK,0);
 
  	digitalWrite(ADC_DIO,1);    delayMicroseconds(2); //CH0 10
  	digitalWrite(ADC_CLK,1);	delayMicroseconds(2);
  	digitalWrite(ADC_CLK,0);
 
  	digitalWrite(ADC_DIO,0);	delayMicroseconds(2); //CH0 0
 
  	digitalWrite(ADC_CLK,1);	
  	digitalWrite(ADC_DIO,1);    delayMicroseconds(2);
  	digitalWrite(ADC_CLK,0);	
  	digitalWrite(ADC_DIO,1);    delayMicroseconds(2);
 
  	for(i=0;i<8;i++)
  	{
  		digitalWrite(ADC_CLK,1);	delayMicroseconds(2);
  		digitalWrite(ADC_CLK,0);    delayMicroseconds(2);
 
  		pinMode(ADC_DIO, INPUT);
  		dat1=dat1<<1 | digitalRead(ADC_DIO);
  	}
 
  	for(i=0;i<8;i++)
  	{
  		dat2 = dat2 | ((uchar)(digitalRead(ADC_DIO))<<i);
  		digitalWrite(ADC_CLK,1); 	delayMicroseconds(2);
  		digitalWrite(ADC_CLK,0);    delayMicroseconds(2);
  	}
 
  	digitalWrite(ADC_CS,1);
 
  	pinMode(ADC_DIO, OUTPUT);
 
  	return(dat1==dat2) ? dat1 : 0;
  }
 
  int main(void)
  {
  	uchar adcVal;
  	float vol;
 
  	if(wiringPiSetup() == -1){
  		printf("setup wiringPi failed !");
  		return 1; 
  	}
 
  	pinMode(ADC_CS,  OUTPUT);
  	pinMode(ADC_CLK, OUTPUT);
 
  	while(1){
  		pinMode(ADC_DIO, OUTPUT);
  		adcVal = get_ADC_Result();
  		vol = 3.3/255 * adcVal;
  		printf("analog value: %03d   voltage: %.2fV\n", adcVal, vol);
 
  		delay(100);
  	}
 
  	return 0;
  }

Python code:

  #!/usr/bin/env python
  import ADC0832
  import time
 
  def init():
  	ADC0832.setup()
 
  def loop():
  	while True:
  		res = ADC0832.getResult()
  		vol = 5.0/255 * res
  		print 'analog value: %03d  ||  voltage: %.2fV' %(res, vol)
  		time.sleep(0.2)
 
  if __name__ == '__main__':
  	init()
  	try:
  		loop()
  	except KeyboardInterrupt: 
  		ADC0832.destroy()
  		print 'The end !'
 

For C language users:

Step 2: Edit and save the code with vim or nano.

(Go to the folder where the code is stored)

Step 3: Compile

$ sudo gcc potentiometer.c -o potentiometer -lwiringPi

Step 4: Run

$ sudo ./potentiometer

For Python users:

Step 2: Edit and save the code with vim or nano.

Step 3: Run

$ sudo python potentiometer.py

Turn the knob on the Potentiometer module, you will find that the value displayed on the terminal is changed.

Data code:potentiomenter_module.rar
Video link:http://www.adeept.com/video/