Potentiometer Part 2

Arduino Examples

Analog Read Serial and Read Analog Voltage

Reads an analog input on pin 0, prints the result to the serial monitor

CODE FROM ARDUINO.CC 

 Both of these examples use the same wiring and component (10k ohm Potentiometer), but the programs are different. Both use the UNO R3 Boards analog-to-digital converter.

I had trouble getting the Raspberry Pi Zero to run these two sketches, they did run but the read out was very slow and not showing the results equal to where the knob was on the potentiometer. The Raspberry Pi 3 was able to run these okay.

Analog Read Serial:

In this program the  analog-to-digital converter shows the resistance of the Potentiometer in a value between 0 to 1023 in the Serial Monitor (which you get by clicking on the magnifier on the upper right side of the Arduino IDE).

/*
  AnalogReadSerial
  Reads an analog input on pin 0, prints the result to the serial monitor.
  Graphical representation is available using serial plotter

  (Tools > Serial Plotter menu)
  Attach the center pin of a potentiometer to pin A0,

  and the outside pins to +5V and ground.

  This example code is in the public domain.
*/

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue = analogRead(A0);
  // print out the value you read:
  Serial.println(sensorValue);
  delay(1);        // delay in between reads for stability
}

Analog Read Serial Output

Read Analog Voltage:

This time the analog-to-digital converter shows the resistance of the Potentiometer in volts from 0 to 5 volts in the Serial Monitor.
 

/*
  ReadAnalogVoltage
  Reads an analog input on pin 0, converts it to voltage, 

  and prints the result to the serial monitor.
  Graphical representation is available using serial plotter

  (Tools > Serial Plotter menu)
  Attach the center pin of a potentiometer to pin A0,

  and the outside pins to +5V and ground.

  This example code is in the public domain.
*/

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue = analogRead(A0);
  // Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
  float voltage = sensorValue * (5.0 / 1023.0);
  // print out the value you read:
  Serial.println(voltage);
}

Read Analog Voltage Output

I think I will be coming back to the Potentiometer, when I have more understand of programming, and electronics.

Potentiometer Part 1

Potentiometer (a three terminal resistor), a nob that provides variable resistance.

Second example from Sparkfun varies the speed of an LED blinking, and from the Arduino IDE Basics example Read Analog Voltage.

First the Sparkfun example:

Instructions and code at: https://learn.sparkfun.com/tutorials/sik-experiment-guide-for-arduino---v32/experiment-2-reading-a-potentiometer

Wiring and items used diagram

What it really looks like

The video shows what the programme and the components actually do, as you turn the nob on the Potentiometer it varies the speed of the LED blinking. Cannot say I fully understand the programme, but do get the gist of what each line does.

Arduino - Blink LED

Thankfully the first example for the Arduino is easy to understand, both the wiring and the code. First I just tried the example using the LED on the UNO R3, then I looked on the web for more detail and examples.

Next I put an LED into the pins (positive in pin 13 and negative into the GND pin next to 13).

 and then I read if you want the LED to last you need to use a resistor, so I then find 2 different ways of wiring up a breadboard for the Blink example with a resistor.

I liked the explanation and diagrams from Sparkfun for their SIK Experiment Guide for Arduino - V3.2.

Link:  https://learn.sparkfun.com/tutorials/sik-experiment-guide-for-arduino---v32

I do not have the kit (might get it), so for now cannot do all the examples (yet). But it looks like a great site for beginners.

Starting a journey of learning and fun

This is going to be more a diary of what I have done and learnt sort of blog, as it is nearly all new to me, especially the electronics and programming.

I got a Raspberry Pi Model B and a Model A a few years ago, and they ended up in a cupboard. Now they have been dusted down and been joined by a Raspberry Pi Zero (I got free with issue 40 of The MagPi), and a Raspberry Pi 3 Model B+, so I got to start learning how to use them.

The Arduino is something that has looked interesting to me for a little while, as I am interested in how things are made and work, but my lack of knowledge about electronics has always put me off. I took the plunge and bought an Arduino UNO R3 copy, as it is cheaper if I do anything drastically wrong at the beginning. When I get a bit more confident one will buy an official board.

Raspberry Pi Zero

At the moment I have set up the Raspberry Pi Zero for programming the UNO R3, I've installed the Arduino.cc IDE and Fritzing onto it. The reason for choosing the Raspberry Pi Zero is that it comes with no GPIO pins.

UNO R3