Electronic Technologies for Art II (electric boogaloo)

Mark Allen

UCSD

Overview

• Introduction
• Microcontroller 101
• Lab set up
• Hello World

Goals

• gain general familarity with materials and concepts of class
• understand the basic elements of electronics
• set up computers and basic stamp for programming
• understand + build basic schematic
• write first program

Materials

• computer
• basic stamp homework board
• serial cable, usb to serial converter
• resistor
• led

How to succeed at electronics

• Document your process
• Buy your way out of trouble
• Remain flexible
• Expect things to go wrong
• Collaborate
• Try to avoid reinventing the wheel

Interactivity

• Input – sense something. Human moves in front of motion sensor
• Processing – decide what to do. If human present, activate defense system
• Output – do something. Turn on flamethrower.

Transduction

• Conversion of one form of energy to another
• Sensors convert physical changes (heat, sound, motion) to electricity
• Motors, Electromagnets, Toasters convert electrical energy into other forms of energy such as heat or kinetic energy

Digital vs Analog

• Digital is on/off. Push button switch, beam break detection.
• Analog covers range of value. Temperature, brightness, volume

Microcontrollers

• Computer with I/O designed for electronics
• Cheap + Small
• Uses electricity as information
• Interfaces with transducers
• Compilier running on PC turns human readable code into instructions for microcontroller
• Hardware (burner) connected to PC transfers instructions onto microcontroller

Basic Stamp overview

• Pro: Basic Stamp software is a (free) basic compilier and IDE (Integrated development environment)
• Pro: Basic stamp hardware eliminates the need for seperate hardware to transfer code onto stamp
• Pro: Oodles of users
• Pro: Easy
• Con: Expensive
• Con: Slow

Homework board wiring

• Vin : unregulated voltage into stamp
• Vdd : regulated 5v, 100 m.a. max current
• Vss : Ground
• P0-P15 : Input/output pins. Each pin can source 20ma max, sink 25ma max

Digital output schematic

Hello World code

• Main: ' label
  high 7 ' set pin 7 to 5v
  pause 100 ' do nothing for .1 seconds
  low 7 ' set pin 7 to gnd
  pause 100 ' do nothing for .1 seconds
  Goto Main ' go to label "Main"

Programming procedure

• Connect stamp to computer via serial cable or usb to serial converter
• Make sure stamp has power
• Launch basic stamp application
• (windows) choose bs2 icon. it's green and near the middle of the tool bar
• (windows) choose language version 2.5. it's a cog with 2.5 on ito the right of the bs2 icon
• click the run button to download code into the stamp

Debugging

• Does stamp have power?
• Is resistor the right value? (220 ohm)
• Does LED work?
• Is compiler finding the stamp? try using the id button in the tool bar