These days it seems as if everybody talks about the internet of things (IoT). With a cheap Arduino, Raspberry PI (or another microcontroller) every developer has the power to control the real world. Suddenly confronted with resistors, digital inputs, analog interfaces and a weird bread board full of holes – a developer is reminded that the world of hardware can be confusing and sometimes downright frustrating.

1. Dror Helper
drorh@codevalue.net | @dhelper | http://blog.drorhelper.com
Electronics 101 for software developers

2. • Consultant @CodeValue
• Developing software (professionally) since 2002
• Clean coder & Test Driven Developer
• OzCode Evangelist
• Blogger: http://blog.drorhelper.com
About.ME

3. ???

4. We’re surrounded by it
Affect the real world
Connect to your environment
Control cool gadgets
IoT, IoT, IoT!
It’s fun & easy 
Why should you care about Electronics?

5. INTRODUCTION TO ELECTRONICS

6. Electricity & water

7. What would happen if we raise one side
V
I
R

8. • Electric potential energy per unit charge
• Measured in Volts (V)
Voltage
V V
in

9. • The quantity of charge that flows through the circuit
• Measured in Amperes (A)
Current

10. Resistance
• The difficulty to pass through an electric conductor
• Measured in ohm(Ω)

11. Color 1st 2nd 3rd Multiplier Tolerance
Black 0 0 0 1
Brown 1 1 1 10 ±1%
Red 2 2 2 100 ±2%
Orange 3 3 3 1K
Yellow 4 4 4 10K
Green 5 5 5 100K ±0.5%
Blue 6 6 6 1M ±0.25%
Violet 7 7 7 10M ±0.10%
Grey 8 8 8 ±0.05%
White 9 9 9
Gold 0.1 ±5%
Silver 0.01 ±10%
Resistor values
220Ω (±5%)
4.7KΩ (±10%)
1KΩ (±1%)
330KΩ (±0.5%)
2 2×10
4 7×100
1 0×100
3 3×10K

12. I X R = V
I  current
R  Resistance
V  Voltage
Ohm Law
I
RV
I

13. Using Ohm law
312V
I = ?
Calculate current in the system Decide which resistor to use
R=?12V
I = 0.024A

14. The overall amount of work being done in a system in relation to time
Measured in Watts(W)
𝐼 × 𝑉 = 𝑃
Power
𝑃𝑖𝑛 > 𝑃𝑎𝑙𝑙𝑜𝑤𝑒𝑑 = 𝐵𝑂𝑂𝑀!

15. Parallel circuits
R1=5012V R2=200
𝐼𝑡𝑜𝑡𝑎𝑙 = 𝐼1 + 𝐼2 =
𝑉
𝑅1
+
𝑉
𝑅2
𝑉𝑡𝑜𝑡𝑎𝑙 = 𝑉1 = 𝑉2
𝑅𝑡𝑜𝑡𝑎𝑙 =
1
1
𝑅1
+
1
𝑅2
𝑅 =
1
1
50
+
1
200
= 40
𝐼 = 12
40 = 0.3𝐴

16. Series circuit
R1=50
12V
R2=200
𝐼𝑡𝑜𝑡𝑎𝑙 = 𝐼1 = 𝐼2
𝑉𝑡𝑜𝑡𝑎𝑙 = 𝑉1 + 𝑉2
𝑅𝑡𝑜𝑡𝑎𝑙 = 𝑅1 + 𝑅2
𝐼 =
12
200 + 50
= 0.048𝐴
V2 = ?
𝑉2 = 𝐼 × 𝑅2 =
𝑉𝑠
𝑅1 + 𝑅2
× 𝑅2 =
𝑉𝑠 × 𝑅2
𝑅1 + 𝑅2
= 9.6𝑉

17. CONNECTING COMPONENTS

18. Introducing the Light Emitted Diode (LED)
• Allow current only in one direction
• Has two legs – long leg should face the +
Now let’s make something sparkle
+
-

19. 1. Keeps components in place
2. Connects components
Solderless breadboard

20. Using a breadboard
Be organized and eliminate wiring
Never short-circuit

21. Adjustable resistor
OR
Adjustable voltage divider
The potentiometer

22. Using the potentiometer
R1
V
R2

23. Say hello to my little friend

24. Connecting the right inputs

25. Tips on using the multimeter
Measure Resistance without current
Measure Voltage in parallel
Measure Current in series

26. On demand break/connect
Push buttons/Switches

27. Using buttons

28. Can you guess what this is?
a
b
c
d
e
f
a
g
d
bf
e c

29. HELLO MICRO CONTROLLERS

30. Microcontroller example: Arduino Uno

31. Generic pin on an integrated circuit
Can be controlled by user at run time.
There are digital and analog pins
General purpose Input/Output (GPIO)

32. Digital and analog signals
X = LOW/HIGH
0 ≤ X ≤ Max

33. Using GPIO

34. Using sensors
R2
R1
5v
A0
V2

35. 1. Where to connect the GND
2. Where to connect Vin and/or Signal
3. Maximum Power (V x I)  resistance
Tip: try to find circuit schema online
What to look for before connecting a sensor

36. RESOURCES
Where to go from here?

37. How to start
Buy a starter kit
• Sunfounder
• Sparkfun
• Seeed
• Make
• Keyes [insert number here] in 1
Build your own kit
• Breadboard, Resistors, LEDs, sensors
• Google for ideas
• Choose a project and go from there

38. 123d Circuits (https://123d.circuits.io)
Fritzing (http://fritzing.org/)
Useful (and free) software

39. Books
Ebooks: www.oreilly.com coupon code: TS2016
Print: www.wordery.com

40. Arduino: https://www.arduino.cc/
Raspberry PI: https://www.raspberrypi.org/
Windows 10 IoT: https://dev.windows.com/en-us/iot
Make: http://makezine.com/
Stack Exchange sites:
Electrical engineering http://electronics.stackexchange.com/
Raspberry PI http://raspberrypi.stackexchange.com/
Arduino http://arduino.stackexchange.com/
Additional resources

41. Dror Helper
C: 972.05.7668543
e: drorh@codevalue.net
B: blog.drorhelper.com
w: http://www.oz-code.com