Named after the gorgeous giant silk moth with large, colorful “eyespots” on its hind wings (Antheraea polyphemus), as well as the gigantic Cyclops who tormented Odysseus, this Polyphemus sports several exciting features:

ATmega 168 microcontroller (housed on a Freeduino board)color Nokia 6100 LCDtwo multi-state pushbuttonswhite LEDphototransistorpiezoelectric buzzer3.7V rechargeable lithium batteryanalog input connectorFTDI USB programming connectorcompact 3×3-inch handheld form factor

By using a 3.7V battery to power Polyphemus, no additional power regulators are needed. Also, no DC-DC boost converter is needed for powering the Freeduino and white LED. The user interface for Polyphemus is displayed on the color Nokia 6100 LCD. Using one pushbutton to move the menu and the other to “pick” a selection, you can choose from three built-in functions:

Flashlight – turn ON/OFF the white LEDLight sensor – sample ambient light readings in milliamp unitsVoltmeter – test power connections ( 5VDC)

BUILD IT! TIME: 13 hours COST: Varies; all new parts $78.60 DIFFICULTY: Moderate PARTS You can build this “kit” from off-the-shelf parts–no printed circuit boards are needed. Also, you can add, replace, or substitute your own parts for the parts recommended in Polyphemus (e.g., if you don’t have a white LED, try another color of LED).

(1) carrier board (SparkFun Electronics #LCD-00600; $39.95)(1) RBBB Freeduino Kit Plus (Wulfden at Hawk’s Mountain; $14)(1) White LED 10,000 mcd 3.3V ([Mouser #859-LTW-2S3D7; $0.41)(1) Ambient light sensor ([Mouser #513-NJL#7502L; $0.36)(1) 3V rechargeable batteries (SparkFun Electronics #PRT-08818; $4.95)(1) 24mm coin cell holders (DigiKey #BH2430T-C-ND; $0.95)(1) Yellow SPST switch (DigiKey #401-1984-ND; $0.99)(1) Red SPST switch (DigiKey #401-1985-ND; $0.99)I used an obsolete DBX-01PN buzzer; try this buzzer, instead: (1) CEM-1201 1.5V buzzer (DigiKey #102-1152-ND; $0.63)(2) 10K resistors (Mouser #660-CFP1-4CT52R103J; $0.10)(1) 1K resistor (Mouser #660-CFS1-4C102J; $0.05)(1) 22-ohm resistor (Mouser #660-CFS1-4CT52R22OJ; $0.05)(1) SPDT switch (SparkFun Electronics #COM-00102; $1.50)(1) JST right angle connector (SparkFun Electronics #PRT-08612; $0.95)(1) 2-position JST plug housing + pins (DigiKey #455-1165-ND; $0.46)(1) Mini hook test connector, red (DigiKey #461-1014-ND; $1.74)(1) Mini hook test connector, black (DigiKey #461-1013-ND; $1.74)(1) 2 ¾- x 6 1/16-inch perfboard (RadioShack #2761395; $2.79)hookup wire (RadioShack #278-1224; $5.99)

STEPS

  1. Download our Polyphemus project archive. Inside this ZIP file you will find source code, board layout information, datasheets, and image files.
  2. Cut the perfboard into two pieces. One piece will hold the Freeduino, LED, battery holder, and phototransistor, while the second piece will support the Nokia color LCD, pushbuttons, buzzer, analog connector, and power on/off switch.
  3. Mount the Freeduino and support components on the lower piece of perfboard.
  4. Mount the Nokia LCD and support components on the upper piece of perfboard.
  5. Use small lengths of wire to route connections between the Freeduino, the support componets, and the Nokia LCD.
  6. Connect the negative terminal of the battery holder to one terminal of the on/off power switch. Connect another length of wire from the switch to the Freeduino.
  7. Use the free Arduino programming environment for loading the Polyphemus code on the Freeduino.
  8. Insert the battery into the battery holder (watch the holder’s polarity!) and turn on the power switch. In a couple of seconds, the buzzer will beep twice and the main menu screen will be displayed. The complete sketch weighs in at slightly less than 6kb. Feel free to evaluate your own components on Polyphemus. Remember to avoid Port B when adding new components (it’s used for communicating with the LCD). Now don’t let some “geeks” poke your eye out.