[Noisebridge-discuss] door code keypad idea times two

Jake jake at spaz.org
Fri Feb 10 04:36:53 PST 2012

Rachel Lyra wrote:
> What about a code being required in order to operate the buzzer from 
> the inside, ie you need to know a code to let other people in?

I like this idea the best.  It is basically Kelly's hot-tub code idea 
extended to the button at the top of the stairs (inside) as well.

what we need is a keypad terminal that operates over a serial connection 
to a computer like minotaur (the circuitboard screwed to the Wall O Tubes 
above the "server room" door).  minotaur has several serial ports already, 
and also happens to be the computer that activates the door-opener through 
its USB parallel port.

the terminal would be a boarduino connected to a (metal payphone) numeric 
keypad, a few LEDs, and a speaker.  It would accept keypresses and make a 
pleasing beepy noise as they're entered, and then make a happy or sad 
noise depending on the response from the other end of the serial line.

It would be a simple hardware terminal for this purpose, and if someone 
else will code up the software, i will build the hardware.

and we can put one at the upstairs buzzer by the door, and another one at 
the sidewalk by the gate!  two birds with one stoned!


P.S. the serial interface would be simple - keypresses (including * and #) 
are passed from the terminal to the computer as ascii, when they happen. 
The computer sends single-byte commands to the terminal to make tones of 
different frequencies and durations, or to turn on or off the LEDs.

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