Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Building Your Own Lightsaber
Search
Pete Hodgson
January 03, 2014
Programming
104
6.3k
Building Your Own Lightsaber
Presented at CodeMash 2014
Pete Hodgson
January 03, 2014
Tweet
Share
More Decks by Pete Hodgson
See All by Pete Hodgson
Migratory Patterns - KubeCon Salt Lake City, 2024
phodgson
0
72
A Journey Into Feature Toggles - OSCON Austin 2017
phodgson
5
590
Test-driven Client-side JS
phodgson
5
820
Functional Reactive JavaScript
phodgson
8
780
different.js - Forward JS 2014
phodgson
4
810
Railsconf2014
phodgson
7
1.4k
iOS Unit Testing Workshop
phodgson
3
510
Multi-platform Mobile with Calatrava - May 2013
phodgson
2
490
Unit testing with Kiwi - CocoaConf San Jose 2013
phodgson
1
650
Other Decks in Programming
See All in Programming
Fiber Scheduler vs. General-Purpose Parallel Client
hayaokimura
1
290
Amazon CloudWatchの地味だけど強力な機能紹介!
itotsum
0
230
note の Elasticsearch 更新系を支える技術
tchov
9
3.4k
eBPF超入門「o11yに使える」とは (20250424_eBPF_o11y)
thousanda
1
110
AI時代の開発者評価について
ayumuu
0
230
API for docs
soutaro
3
1.6k
M5UnitUnified 最新動向 2025/05
gob
0
120
Носок на сок
bo0om
0
1.1k
20250426 GDGoC 合同新歓 - GDGoC のススメ
getty708
0
110
Dissecting and Reconstructing Ruby Syntactic Structures
ydah
3
2k
Laravel × Clean Architecture
bumptakayuki
PRO
0
130
AIコーディングの理想と現実
tomohisa
35
37k
Featured
See All Featured
GitHub's CSS Performance
jonrohan
1030
460k
The Success of Rails: Ensuring Growth for the Next 100 Years
eileencodes
45
7.2k
How to Ace a Technical Interview
jacobian
276
23k
Optimising Largest Contentful Paint
csswizardry
37
3.2k
Scaling GitHub
holman
459
140k
10 Git Anti Patterns You Should be Aware of
lemiorhan
PRO
656
60k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
14
1.4k
Building a Scalable Design System with Sketch
lauravandoore
462
33k
Practical Tips for Bootstrapping Information Extraction Pipelines
honnibal
PRO
19
1.2k
Let's Do A Bunch of Simple Stuff to Make Websites Faster
chriscoyier
507
140k
KATA
mclloyd
29
14k
Rebuilding a faster, lazier Slack
samanthasiow
81
9k
Transcript
Building your own Lightsaber
me me me Pete Hodgson Consultant at ThoughtWorks @ph1 blog.thepete.net
TSA Pro-Tip™
None
None
Green Field http://www.flickr.com/photos/jillclardy/3213748255
Continuous Integration
Feedback
None
Feedback
http://www.flickr.com/photos/johnmueller/52621490/ what if you have no build box?
None
Raspberry Pi
None
Raspberry Pi
visual indicator aka build light
None
None
Build Light
Pretending to work
raspberry pi & build light
done.
done. ?
build light build my own lightsaber
Learning by Doing
Learning Doing
Learning Doing Learning By Doing
Choose a “right-sized“ problem
build light build my own lightsaber
LEDs low voltage (can be powered via USB) bright flexible
(blinky! colors!)
all the colors
The Drefus Model
Beginner Expert
Beginner detailed step-by-step instructions no wider context
Beginner detailed step-by-step instructions no wider context Expert wider context
(goal) no details (yet)
Know where you are on the Drefus scale
None
all the colors
multi-color LEDs Search
multi-color LEDs Search an LED can only be one color…
but LEDs can come in many colors… solution: combine different colored LEDs
RGB color mixing
vary LED brightness Search
vary LED brightness Pulse Width Modulation P W M Search
Incandescent Bulb Voltage Brightness
LED Voltage Brightness
voltage 100% 0% time brightness: 100%
voltage 100% 0% time
50% on 50% off duty cycle voltage 100% 0% time
50% on 50% off duty cycle brightness: 50% voltage 100%
0% time
voltage 100% 0% time
25% on 75% off voltage 100% 0% time
brightness: 25% 25% on 75% off voltage 100% 0% time
Don't trust your intuition '
Red LED + Green LED + Blue LED + PWM
= all the colors!
None
Raspberry PI red LED green LED blue LED PWM
GPIO Pins
Raspberry Pi has two GPIO pins which capable of PWM
output. Our light needs three.
Arduino
Arduino is an Open-Source electronics prototyping platform based on flexible,
easy-to-use hardware and software. - arduino.cc
Arduino
Raspberry PI red LED green LED blue LED PWM
Raspberry PI red LED green LED blue LED PWM Arduino
???
Feature-creep as a learning tool
Raspberry PI red LED green LED blue LED PWM Arduino
???
None
baby steps, towards an eventual goal.
sketch 1 blinking an LED (Hello World of hardware)
None
IO pin ground pin
None
pin “high” (+ve voltage)
pin “low” (0 voltage)
int LED_PIN = 6;! ! void setup() { ! pinMode(LED_PIN,
OUTPUT); ! }! ! void loop() {! digitalWrite(LED_PIN, HIGH);! delay(1000); ! digitalWrite(LED_PIN, LOW);! delay(1000); ! }!
sketch 2 fading an LED (PWM)
None
int LED_PIN = 6;! int MAX_BRIGHTNESS = 255;! int brightness
= 0;! ! void setup() { ! pinMode(LED_PIN, OUTPUT); ! }! ! void loop() {! analogWrite(LED_PIN, brightness);! ! brightness = brightness + 5;! if( brightness > MAX_BRIGHTNESS )! brightness = 0;! ! delay(30);! }!
int LED_PIN = 6;! int MAX_BRIGHTNESS = 255;! int brightness
= 0;! ! void setup() { ! pinMode(LED_PIN, OUTPUT); ! }! ! void loop() {! analogWrite(LED_PIN, brightness);! ! brightness = brightness + 5;! if( brightness > MAX_BRIGHTNESS )! brightness = 0;! ! delay(30);! }! PWM
sketch 3 mixing colors
None
None
None
int RED_PIN = 3;! int GREEN_PIN = 5;! int BLUE_PIN
= 6;! int MAX_BRIGHTNESS = 255;! ! void setup() { ! pinMode(RED_PIN, OUTPUT );! pinMode(GREEN_PIN, OUTPUT );! pinMode(BLUE_PIN, OUTPUT );! }! ! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); ! }! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);!
int RED_PIN = 3;! int GREEN_PIN = 5;! int BLUE_PIN
= 6;! int MAX_BRIGHTNESS = 255;! ! void setup() { ! pinMode(RED_PIN, OUTPUT );! pinMode(GREEN_PIN, OUTPUT );! pinMode(BLUE_PIN, OUTPUT );! }! ! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); ! }! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);!
int RED_PIN = 3;! int GREEN_PIN = 5;! int BLUE_PIN
= 6;! int MAX_BRIGHTNESS = 255;! ! void setup() { ! pinMode(RED_PIN, OUTPUT );! pinMode(GREEN_PIN, OUTPUT );! pinMode(BLUE_PIN, OUTPUT );! }! ! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); ! }! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);!
! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); !
}! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);! colorComponents[1] = random(MAX_BRIGHTNESS);! colorComponents[2] = random(MAX_BRIGHTNESS);! }! ! void displayColor(byte colorComponents[]){! analogWrite( RED_PIN, colorComponents[0] );! analogWrite( GREEN_PIN, colorComponents[1] );! analogWrite( BLUE_PIN, colorComponents[2] ); ! }!
! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); !
}! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);! colorComponents[1] = random(MAX_BRIGHTNESS);! colorComponents[2] = random(MAX_BRIGHTNESS);! }! ! void displayColor(byte colorComponents[]){! analogWrite( RED_PIN, colorComponents[0] );! analogWrite( GREEN_PIN, colorComponents[1] );! analogWrite( BLUE_PIN, colorComponents[2] ); ! }!
! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); !
}! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);! colorComponents[1] = random(MAX_BRIGHTNESS);! colorComponents[2] = random(MAX_BRIGHTNESS);! }! ! void displayColor(byte colorComponents[]){! analogWrite( RED_PIN, colorComponents[0] );! analogWrite( GREEN_PIN, colorComponents[1] );! analogWrite( BLUE_PIN, colorComponents[2] ); ! }!
! void loop() {! byte color[3];! assignRandomColorTo(color);! displayColor(color);! delay(1000); !
}! ! void assignRandomColorTo(byte colorComponents[]){! colorComponents[0] = random(MAX_BRIGHTNESS);! colorComponents[1] = random(MAX_BRIGHTNESS);! colorComponents[2] = random(MAX_BRIGHTNESS);! }! ! void displayColor(byte colorComponents[]){! analogWrite( RED_PIN, colorComponents[0] );! analogWrite( GREEN_PIN, colorComponents[1] );! analogWrite( BLUE_PIN, colorComponents[2] ); ! }!
Raspberry PI red LED green LED blue LED PWM Arduino
???
Raspberry PI red LED green LED blue LED PWM Arduino
???
Raspberry PI red LED green LED blue LED PWM Arduino
serial
sketch 4 an echo server (serial IO)
void setup()! {! Serial.begin(57600); // start serial port at 57600
bps! }! ! void loop() {! waitForInput();! ! static char input[1025];! int bytesRead = Serial.readBytesUntil( '\n', input, 1024 );! ! if( bytesRead ){! String str = String(input);! str.toUpperCase();! Serial.println(str);! }! }! ! void waitForInput() {! while (Serial.available() <= 0) {! // busy loop! }! }!
void setup()! {! Serial.begin(57600); // start serial port at 57600
bps! }! ! void loop() {! waitForInput();! ! static char input[1025];! int bytesRead = Serial.readBytesUntil( '\n', input, 1024 );! ! if( bytesRead ){! String str = String(input);! str.toUpperCase();! Serial.println(str);! }! }! ! void waitForInput() {! while (Serial.available() <= 0) {! // busy loop! }! }!
void setup()! {! Serial.begin(57600); // start serial port at 57600
bps! }! ! void loop() {! waitForInput();! ! static char input[1025];! int bytesRead = Serial.readBytesUntil( '\n', input, 1024 );! ! if( bytesRead ){! String str = String(input);! str.toUpperCase();! Serial.println(str);! }! }! ! void waitForInput() {! while (Serial.available() <= 0) {! // busy loop! }! }!
void setup()! {! Serial.begin(57600); // start serial port at 57600
bps! }! ! void loop() {! waitForInput();! ! static char input[1025];! int bytesRead = Serial.readBytesUntil( '\n', input, 1024 );! ! if( bytesRead ){! String str = String(input);! str.toUpperCase();! Serial.println(str);! }! }! ! void waitForInput() {! while (Serial.available() <= 0) {! // busy loop! }! }!
void setup()! {! Serial.begin(57600); // start serial port at 57600
bps! }! ! void loop() {! waitForInput();! ! static char input[1025];! int bytesRead = Serial.readBytesUntil( '\n', input, 1024 );! ! if( bytesRead ){! String str = String(input);! str.toUpperCase();! Serial.println(str);! }! }! ! void waitForInput() {! while (Serial.available() <= 0) {! // busy loop! }! }!
void setup()! {! Serial.begin(57600); // start serial port at 57600
bps! }! ! void loop() {! waitForInput();! ! static char input[1025];! int bytesRead = Serial.readBytesUntil( '\n', input, 1024 );! ! if( bytesRead ){! String str = String(input);! str.toUpperCase();! Serial.println(str);! }! }! ! void waitForInput() {! while (Serial.available() <= 0) {! // busy loop! }! }!
Raspberry PI red LED green LED blue LED PWM Arduino
serial
GPIO Pins
Raspberry PI red LED green LED blue LED Arduino
Raspberry PI red LED green LED blue LED Arduino “ffaa11\n”
Raspberry PI red LED green LED blue LED Arduino “ffaa11\n”
Raspberry PI red LED green LED blue LED Arduino “ffaa11\n”
Much Learning Arduino- compatibles bareduinos LPC810 soldering! transistors protoboard fritzing
voltage regulators node.js cctray line-level converters command-line builds C++ on Arduino usb to serial external programmers OSS hardware
Resources
Resources
moredip/aphex (work in progress)
Have FUN!
Pete Hodgson @ph1
[email protected]
these slides http://bit.ly/buildlightsaber