Maker Project Instructions


Workshop Outline

  1. Building a one-computer circuit that flashes code on an LED
  2. Adding a second computer that plays sound instead
  3. Adding a third computer that will adjust speed, tempo or both
  4. Adding a fourth computer that will display parameters on TV

Supplies

    

Building a one-computer circuit that flashes code on an LED

  ;             ATtiny45
  ;              --v--
  ;    rst pb5 -|     |- vcc
  ;     pi pb3 -|     |- pb2 sck
  ;     po pb4 -|     |- pb1 miso          LED
  ;        gnd -|     |- pb0 mosi keyout ---|<--- vcc
  ;              -----  
  ;               8Mhz

Bring power and ground to the board (RadioShack 276-175)
  • From Battery Holder (RadioShack 270-398B)
  • Attach power (red wire) to row X at the top
  • Attach ground (black wire) to Y at the bottom
    

Add the morse computer

See InsertingParts.

We are ready to start wiring the computer using color coded jumper wires. See MakingJumperWires. For ease of parsing of a circuit, these are the conventions we use

  • Power is red
  • Ground is black
  • Signal is white (for complicated circuits other colors may be used)

Use a black wire to route the ground pin of the morse computer to the ground bus (labeled y)

   

Use a red wire to route the VCC pin of the morse computer to the VCC bus (labeled x)

Use a white wire to pull the reset pin up to VCC (eventually you'll use 10k resistors)

    

Plug the LED from "key out" on the morse computer to VCC
  • The long LED leg goes to VCC
  • The morse computer turns the LED on by pulling the short leg down to ground

    

Turn the circuit off by plugging the red VCC wire into an unused breadboard slot

  

Load the battery pack

Turn the circuit in by plugging the red VCC wire back into the VCC bus (yay ... blinky lights)

  • Play with the speed of the code
    • pi listens to the bynase protocol bus to determine how fast to generate the code
    • try connecting pi to ground using a white "signal" wire
    • try connecting pi to vcc
    • What speed would you get if you hooked pi up to keyout?

Adding a second computer that plays sound instead

  ;             ATtiny45
  ;              --v--
  ;    rst pb5 -|     |- vcc
  ;     pi pb3 -|     |- pb2 sck keyin
  ;     po pb4 -|     |- pb1 miso tone1
  ;        gnd -|     |- pb0 mosi tone0
  ;              -----        
  ;		8Mhz

Add the side tone computer
  • Plug the gnd pin into the ground bus
  • Plug the vcc pin into the VCC bus
  • Pull reset (rst) high by plugging it to the VCC bus

  

Now connect keyout from the morse computer to keyin on the side tone computer

Now connect the speaker to + and - tone (doesn't matter which lead you plug into which). See CellPhoneSpeaker.

  

The pi pin on morse controlls the tempo, the pi pin on sidetone controls pitch. Try hooking these to vcc or ground and notice the range of values. Try feeding the morse keyout signal into one or the other or both of the pi inputs. See if it makes you laugh.

    

Adding a third computer that will adjust speed, tempo or both

  ;             ATtiny45
  ;              --v--                     100k
  ;    rst pb5 -|     |- vcc ------------\/\/\/\/---+
  ;     pi pb3 -|     |- pb2 sck adc1 ------^       |
  ;     po pb4 -|     |- pb1 miso pwr --------------+
  ;        gnd -|     |- pb0 mosi scope
  ;              -----        
  ;		8Mhz

Add the adc-pot computer
  • Plug the gnd pin into the ground bus
  • Plug the vcc pin into the VCC bus
  • Pull reset (rst) high by plugging it to the VCC bus

  • Plug the potentiometer into vcc, adc1, and pwr

    

Try using the po from the adc-pot to control the morse tempo or pitch or both.

Adding a fourth computer that will display parameters on TV

  ;             ATtiny12
  ;              --v--
  ;    rst pb5 -|     |- vcc
  ;     pi pb3 -|     |- pb2 sck
  ;        pb4 -|     |- pb1 miso vh --470--+-- 75 ohm video
  ;        gnd -|     |- pb0 mosi vl --1k---+
  ;              -----        
  ;		1.2Mhz

Add the TV computer
  • Plug the gnd pin into the ground bus
  • Plug the vcc pin into the VCC bus
  • Pull reset (rst) high by plugging it to the VCC bus

The video output needs to be connected between the 470 and 1k resistors.
  • Plug the 470 ohm resistor into vh and the unused breadboard slot
  • Plug the 1k ohm resistor into vl and the unused breadboard slot

    

  • Video out is now the summation as created in the unused breadboard slot

    

ToDo

  • Get paint markers to color code computers
  • How bread boards work
  • What kind of wire to use
    • Stranded wire doesn't work
  • Using resistors to pull reset to vcc allows in-place programming
  • How to read resistors

 

Last edited March 19, 2006
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