[hackerspaces] Open Access Control for Hacker Spaces v1.0

[john arclight]

Hi all,

We've got a preliminary hardware design together finally, along with
the code.  Check out the schematic and download links for everything
at:

http://23bshop.blogspot.com/

This system uses the Arduino Duemilanova board and so far has been
breadboard tested to support:

-DS1307 Real-time clock with battery backup
-(2) Wiegand26 reader inputs (optoisolated)
-(4) Alarm zone monitor ports using Analog0..3 (optoisolated)
-(4) Relay outputs, rated to 10A/220VAC
-Spare pins 10..13 to enable Ethernet shield use
-Built in 12V unregulated, 5V regulated, 12V regulated supplies for
alarm sensors, door hardware
-Built in UPS (smart charger in next design)
-Separate fuse protection for everything

So this will basically allow 2 separate Wiegand26 door readers, 4
independent relay outputs for unlocking doors or alarm sirens, 4
inputs for alarm/other sensors, easy upgrade to Ethernet logging.
(It's currently doing Syslog format via USB serial.) It has a built-in
UPS backup, much like a commercial alarm system and it allows multiple
power buses for motion detectors, fire sensors, etc that are separate
form the logic bus. I also put an EMF kick-back diode in for the door
hardware bus (unregulated 12V).
 I would appreciate any feedback in terms of:

1. What additional features would be nice?
2. Any obvious design flaws.

Thanks!

John