1. Binary Counter Thinking Digitally
Lecture 5
Binary Counter
Thinking Digitally
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

2. Henry Farny’s Song of the Talking Wire
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

3. 2 Minute Quiz Name_________________ Sec____
Code Example:
PWM Question:
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

4. Joseph Henry & the Telegraph
Albany Academy Experiment
Assisted Morse at Princeton
1st Head of Smithsonian
Unit of inductance: Henry
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

5. Introduction to Engineering Electronics
Morse Code
Simple sequences of short and long clicks to represent letters and numbers
Easier to generate than sound
Easier to distinguish than sound
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

6. Introduction to Engineering Electronics
UPC Codes
Bars come in four widths
Start is (black-white-black)
0 =
1 =
2 =
3 =
4 =
5 =
6 =
7 =
8 =
9 =
The zero is (space-bar-space-bar).
The four is (space-bar-space-bar).
The three is (space-bar-space-bar).
The next three zeros are (space-bar-space-bar).
In the middle there is a standard (space-bar-space-bar-space), which is important because it means the numbers on the right are optically inverted!
The one is (bar-space-bar-space). …
The stop character is a (bar-space-bar).
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

7. Computer Number System Examples From Computer Science I
binary number
equivalent base 10 value for each group of 4 consecutive binary digits (bits)
B C C F
corresponding hexadecimal (base 16) digit
B5C59CF6
equivalent hexadecimal number
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

8. Communicating With Pulses
PCM: Pulse Code Modulation
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

9. PCM: Pulse Code Modulation
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

10. PWM: Pulse Width Modulation
Signal is compared to a sawtooth wave producing a pulse width proportional to amplitude
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

11. Introduction to Engineering Electronics
Optical Receiver
Receiver detects pulses of light
Pulses are amplified and partly averaged by 741 op-amp (volume adjusted with the pot)
Higher frequencies still in signal cannot be heard
Signal is increased by 386 audio amp
386 audio amp drives the speaker
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

12. Introduction to Engineering Electronics
Optical Transmitter
Audio signal changes thresholds for 555 timer producing a type of pulse width modulation of the light from the LED.
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

13. Signals from Audio Remote
Mostly hear higher frequencies in pulses
3.5 x 20 = 70ms or 14Hz
2 x 100 / 9 = 23us or 43kHz
4 x 500 = 2000us or 500Hz
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

14. Introduction to Engineering Electronics
Binary Numbers
0 0000
1 0001
2 0010
3 0011
4 0100
5 0101
6 0110
7 0111
8 1000
9 1001 =
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

15. Introduction to Engineering Electronics
Binary Counter
Animations showing counter operation
Counter for lab
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

16. Typical Output for Binary Counter
Note how the Q outputs form 4 bit numbers
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

17. Introduction to Engineering Electronics
Digital Pulses
Function generator produces a 1kHz sinusoidal voltage. 1v peak-to-peak (pp)
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

18. Introduction to Engineering Electronics
Digital Pulses
Switch to a square wave at 1kHz. Still 1v pp
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

19. Introduction to Engineering Electronics
Digital Pulses
Add a 0.5 volt offset so that the square wave goes from 0 volts to 1 volt
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

20. Introduction to Engineering Electronics
Digital Pulses
Now the duty cycle is adjusted to 20% to see what a single digital pulse looks like.
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

21. Pulses on a Transmission Line
From Matlab
Pulses propagate down transmission lines at the speed of light. They reflect off of the load if the load is not the same impedance as the line. Lines, sources and loads must be matched.
Cable TV lines are 75 ohms. Cables in the lab are typically 50 ohms.
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

22. What Can Be Done With PWM?
Low
Duty Cycle
Medium
Duty Cycle
High
Duty Cycle
Question: What happens if voltages like the ones above are connected to a light bulb? (4th 2 Minute Quiz Question)
Answer: The longer the duty cycle, the longer the light bulb is on and the brighter the light.
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

23. What Can Be Done With PWM?
Average power can be controlled
Average flows can also be controlled by fully opening and closing a valve with some duty cycle
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

24. What About Analog Modulation?
AM: Amplitude Modulation
FM: Frequency Modulation
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

25. Other Coding Applications
Cryptography
Image Compression
JPEG (Joint Photographic Expert Group)
GIF (Graphics Interchange Format)
TIFF (Tagged Image File Format)
MPEG (Compression of Motion Video)
Most use Discrete Cosine Transform method
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

26. Introduction to Engineering Electronics
Image Compression
2 bpp
0.5 bpp
24 bpp original
(bits per pixel)
Top: JPEG
Bottom: JPEG2K
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor

27. Where Will You See This Material Again?
555 Timer – IEE Lab 6
Digital Counter – IEE Lab 7
Counters: ECSE Computer Components and Operations, ENGR-2350 Introduction to Embedded Control
Signals and Transforms: ECSE-2410 Signals and Systems
Pulse Width Modulation: Embedded Control, ECSE/EPOW-4080 Semiconductor Power Electronics
Pulses on Transmission Lines: ECSE-2100 Fields and Waves I
20 September September 2018
Introduction to Engineering Electronics
K. A. Connor