1. Microcontroller basics
Embedded systems for mortals

2. Lesson 1 Working with Arduino IDE Basic electric components
Your first program
Digital input and output

3. Arduino IDE Download from: http://arduino.cc/en/Main/Software
Version or newer

4. About Arduino Uno 14 Digital I/O pins (6 PWM) Reset button USB port
12 V input
Get its name Uno, meaning one in Italian, because it was first released at the same time as Arduino IDE version 1.0
Pin 13 is also assigned to the intregrated LED
GND is ground, 5 Volt is and 5 volt output
6 Analog Input pins
3.3 V and 5 V outputs

5. Setting up Arduino IDE
Remeber to all check that the port is correct! (COM4 for example)

6. Structure of an Arduino code
1. Define Variables
Before going to the setup function constant variables should be defined
int pin = 1;
2. Setting up functions
void setup() {}
Setup function is run once, when the microcontroller boots up or resets.
After setup function the processor moves to run code inside the loop function. Code inside loop function will be run over and over until the microcontroller is shut down.
void loop() {}
3. Eternal loop
It’s required to have both setup() and loop() functions in the code

7. Arduino C – Basic functions
pinMode(var1, var2)
pinMode functions sets the mode of given pin. Var1 is the number of the pin and var2 is the mode (INPUT, INPUT_PULLUP, OUTPUT)
digitalWrite(var1, var2)
digitalWrite changes the status of the pin. Var1 is the number of the pin and var2 is the status (LOW, HIGH).
IMPORTANT TO NOTICE:
Depending whether the pin is set as an OUTPUT or INPUT the actual effect of digitalWrite() is different
INPUT_PULLUP uses an internal pullup resistor: Unlike pinMode(INPUT), there is no pull-down resistor necessary. An internal  20K-ohm resistor is pulled to 5V. This configuration causes the input to  read HIGH when the switch is open, and LOW when it is closed.
Explain about the need of a pull-up or pull-down resistor

8. Writing your first program
Basic blinking LED
int ledPin = 13; //Variable to store the pin number
void setup() {
pinMode(ledPin, OUTPUT); //set ledPin as output }
void loop()
digitalWrite(ledPin, HIGH); //LED ON
delay(1000); //Wait 1000ms (=0,1s)
digitalWrite(ledPin, LOW); //LED OFF
delay(1000); //Wait 1000ms (=1s)

9. Uploading the program Click Verify The program is checked Click Upload
The program is uploaded to the Arduino mCu board 2. 1.

10. Breadboard
Terminals with blue and red lines are called power busses and are connected together horizontally.
Terminals in the middle are connected together vertically. The gap in the middle separates the two sides.

11. Basic Components Passive components Active components Resistor LED
Capacitor
Transistor
Push button
Integrated circuit (IC)
IC contains a lot of transistors.
Inductor

12. Example 2 – Push Button
Reading digital input

13. Example 2 - Code Reading digital input (Using push button)
byte ledPin = 13;
byte buttonPin = 2;
void setup() {
pinMode(ledPin, OUTPUT);
digitalWrite(ledPin, LOW); //set ledPin off as default
pinMode(buttonPin, INPUT); //set buttonPin as input
digitalWrite(buttonPin, HIGH); //set the default state of the pin to HIGH (+5V) }
void loop()
if(digitalRead(buttonPin) == LOW)
digitalWrite(ledPin, HIGH); //LED ON
else
digitalWrite(ledPin, LOW); //LED OFF

14. Microcontrollers typically operate on low voltages (0-5V) →You must be careful when connecting devices
Know the electrical limits of the microcontroller: Uno can handle max 5V/40mA per pin
Always double check the wiring! If you see smoke it’s already too late!

15. P=U*I M U=R*I
To prevent overloading a pin or a component with excessive current you need to use a resistor
Example: Using an LED – Calculating the required resistor size
Operation voltage for LED: 5V
Recommended current 23mA
𝑈=𝑅∗𝐼→𝑅= 𝑈 𝐼 = 5𝑉 0,023𝐴 ≈220Ω
Ask the class, wha is calculated?

16. Check resistor power-rating
Check resistor power-rating! These resistors are meant for signal processing (max.25 W)

17. Example 3 – adding a LED
Longer pin

18. Analog input Timers Interrupts
In next lesson
Analog input
Timers
Interrupts