Making things senseUrban sensing and physical computing

Day 2 (7-8 May 2011)

Markus RittenbruchQUT Urban Informatics / FAST & NICTA

Schedule - Day 2

• 12:00 - 12:10 Introduction

• 12:10 - 12:30 Analogue sensors

• 12:30 - 13:00 Activity

• 13:00 - 14:00 Sharing sensor data

• 14:00 - 14:10 Short break

• 14:10 - 16:10 Project activity

• 16:10 - 16:50 Project presentations

• 16:50 - 17:00 Wrap up

Making things sense - Day 2

Programming

ProgrammingData types

When variables are made to exceed their maximum capacity they "roll over" back to their minimum capacity, note that this happens in both

directions.

int x

x = -32,768;

x = x - 1; // x now contains 32,767 - rolls over in neg. direction

x = 32,767;

x = x + 1; // x now contains -32,768 - rolls over

Float & casting:

ProgrammingFloat & casting:

int x; int y; float z;

x = 1; y = x / 2; // y now contains 0, ints can't hold fractions z = (float)x / 2.0; // z now contains .5 (you have to use 2.0, not 2)

Resources• Language reference:

• http://www.arduino.cc/en/Reference/HomePage

• http://arduino.cc/en/Reference/Extended

• General code library:

• http://arduino.cc/en/Reference/Libraries

• Interfacing with hardware:

• http://www.arduino.cc/playground/Main/InterfacingWithHardware

• Examples

• http://arduino.cc/en/Tutorial/HomePage

Analogue sensors

Analogue sensor pins

• Use analogue in pins 0-5 for analogRead()

• Address as 14-19 when used as digital pins

• digitalWrite(), digitalRead()

• No pinMode required for analogRead();

Analogue sensor input

• File/Examples/Analog/AnalogInput

Analogue sensor input

Programming Conditionals

http://www.ladyada.net/learn/arduino/lesson5.html

AnalogInput

Calibration - part 1

Calibration - part 2

• map(): remap a number from one range to another

• val = map(val, 0, 1023, 0, 255);

• constrain(): constrain to a number range

Project activity 1 -Calibration

Components

• RGB LED:

Components• LED matrix

http://www.sparkfun.com/datasheets/Components/LED/YSM-1288CR3G2C.pdf

Components• MAX7219 LED driver

http://arduino.cc/playground/Main/MAX72XXHardware

http://www.arduino.cc/playground/Main/LEDMatrix

Project activity II -Projects

So, you’ve got an Arduino and now you want to

make it talk

Or, maybe you want to

talk to it...

...from the other side of the world

This session of the workshop will show you some ways of doing that.

Arduino to the world

• Arduino direct to Pachube via ethernet/wifi shield

• Or Arduino to PC via serial, then to Pachube/Twitter

• We’re taking the second approach in this workshop, since the kits we provided don’t include ethernet/wifi shields

Step 1: Register a feed on Pachube

Step 2: Write some code

Arduino Sketch

Ruby “Bridge”: setup

Ruby “Bridge”: the loop

Step 3: See your data on Pachube

Advanced topics• PCB design

• Wireless communication

• Xbee

• Bluetooth

• Wifi

• Infrared

• Radio

• Real-time communication

• Multi-tasking

Resources

• http://apiwiki.twitter.com/

• http://community.pachube.com/api

• http://community.pachube.com/tutorials

• http://community.pachube.com/triggers/twitter

What next?• Hackerspace Brisbane

• http://hackerspaces.org/wiki/Hackerspace_Brisbane

• Living Dolls (The Edge)

• http://edgeqld.org.au/blog/2011/04/07/living-dolls/