EE460 Reverse Engineering

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File:Iclicker-top.jpg
The i>clicker wireless voting device.

The i>clicker is classroom voting system that allows many students to submit answers to a computerized system, which instructors can use to evaluate student understanding of material and perform in-class quizzes. The i>clicker remote is a 6-button device with 3 LEDs to display power, battery, and vote status to the user, a 900MHz ISM band transceiver for submitting and receiving votes/status. It runs on 3 AAA batteries, measures 6" x 2" x 0.5", and weighs 3 ounces. It can be purchased from online retailers or in stores for approximately $35.

Teardown/Disassembly Procedure

  • Step 1:
    • Remove the batteries and battery door

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  • Step 2:
    • Remove the three screws holding the case together

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  • Step 3:
    • Lift battery connectors out from case
    • Lift PCB out from case

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  • Step 4:
    • Remove two screws holding the PCB to the chassis
    • Pop out the tab holding the LCD to the PCB

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Improvements

Our group had a discussion on possible improvements to the device according to the SCAMPER method, which provides a list of ways that a product could improve.

  • Substitute: Decrease time to sleep, decrease LED brightness (substitute higher resistor values)
  • Combine: Combine microcontroller and transceiver, example ICs: TI's CC1110F8, which combines a comparable microcontroller and transceiver IC on a single chip at a lower price point (per 1k units)
  • Adapt: Dual use as a Powerpoint or presentation slide controller
  • Modify: Change LED color
  • Put to other uses: Add a question asking queue
  • Eliminate: Make the device shorter and thinner to conserve material and lower costs
  • Rearrange or Reverse: Move LEDs to accomodate the smaller size, use a different antenna, change the number or type of batteries

The following ideas could improve the sustainability of the device:

  • Use rechargable batteries
  • Use a biodegradable casing or make the device easier to disassemble for recycling
  • Add instructions for sustainably disposing of the device

The following ideas could reduce manufacturing costs for the device:

  • Remove screws, change design to a snap-together case
  • Use a lower volume of plastic in the construction
  • Move to a smaller design

IC List

Component Additional Text Manufacturer Function
XE1203FI063 UC439026 Semtech - XE1203F Single chip 433, 868 and 915 MHz ISM band transceiver. Up to +15dBm Output power and -114dBm sensitivity.
G3A Unknown RF Transmit/Receive switch
ATMEGA8L 8AU 1026G Atmel - ATmega8(L) 16MHz 8kB Microcontroller with built in 8-channel A/D and 23 programmable I/O.
L0RB Unknown 3.3V Linear/LDO Regulator
39A000 F0AB Unknown 39MHz Crystal Oscillator
4A000 F0AB Unknown 4MHz Crystal Oscillator

Additional Photos