USB Auth1.2

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  • Troubleshooting note: If the USB Auth system is unresponsive, cycle the laptop (located above the fridge as of 11/27/09). What has possibly happened is that the script believes the Arduino is at a different location than it actually is, and does not know to scan for an update. When the script initially runs at boot-up it will scan for the device. Omegix 17:46, 27 November 2009 (CST)
    • Short term fix for this is to have the script self cycle every 30 minutes until it can be figured out why it's loosing track of the Arduino.
  • 1.2 design is currently using the 1.5 AVR Protocol
  • Need to figure out how to up the output voltage from the arduino pin from 3v to the 5v that the radioshack reed relays need in order to close properly. There are two of these installed on the blank arduino sheild Omegix 15:10, 18 June 2009 (CDT)
  • Can't find the blank Arduino shield that was purchased from Preauxphoto. Lost somewhere in a box from the move most likely. Omegix 15:10, 18 June 2009 (CDT)
  • Omegix is not available to work on 1.2 till next week, Ratmandu may have 1.2 functional by the next meeting, possibly operating as well. No promises. Omegix 15:03, 17 June 2009 (CDT)
  • Have gone back to using an Arduino for the purposes of getting it done sooner than having better features. Will concentrate on features in V 2.0 Omegix 15:03, 17 June 2009 (CDT)
  • Awaiting availability from Ratmandu for the week of the 22nd Omegix 13:24, 16 June 2009 (CDT)
  • Ratmandu has hardware started (where in the shop is the hardware located?)
    • Selected Atmega644 chip as microprocessor

Parts List


  1. Two Reed switches (provided from Ratmandu's collection of parts)
  2. AVR Atmega644 (provided by Ratmandu
  3. USB to Serial(TTL), uses an FTDI chip (provided by Ratmandu)
  4. USB Cable
  5. USB Hub (leftover from implementation of USB_Auth 1.0)
  6. Prototyping board
  7. Enclosure

Pin Assignments

  • On the Atmega644, PortA is being used for inputs
    • Reed Switch sensor
    • Manual Override
  • On the Atmega644, PortB is being used for outputs
    • RGB LED to be mounted outside for the user to see whether a command was issued to unlock the door
      • Good troubleshooting indicator
    • Open Door Signal
    • Close Door Signal
  • On the Atmega644, PortD is being used for Tx/Rx serial communication
    • Rx is Pin14
    • Tx is Pin15

Design Notes

The Powerbolt1000 has a mechanical override (regular deadbolt latch), however that would take all the fun out of it, so we will be implementing an electrical override in the design as well.

A piezoelectric speaker is built into the original design of the Powebolt, which will create noise when it receives and open or lock signal.