A summary of Senate Bill 0674 and its companion House Bill 0701 is found at the state legislature’s website.
Update, 9/11/2014: I found the exact manual for the Coinco acceptor, this replaces the previous version. I have also found a manual for the 120VAC relay that the coin acceptor controls.
The next update to this post will contain schematics and some thoughts on where to exploit the relay or Coinco acceptor with a prototyping board.
Update, 11/ 2/2014: I’ve added a schematic below the description of the machine and some more information about the circuit between the coin changer, the Jones plug it uses to interface with the hardware of the vending machine, and the relay that initiates different “states” of the vending machine.
My hypothesis is that the three states that the machine exists in are standby (or ACCEPT COINS), selection mode, and the mechanical delivery/vending of cans. These three modes appear to be controlled by a relay with three switches (a double throw triple pole relay, technically). More information in the Relay section.
Also, I should mention that I am not an electrician. This documentation is for myself and as a reference for people I will be consulting with.
An Overview of the Vending Machine
The Dixie-Narco machine that the Nashville Bitcoin Network is collectively hacking is from the late ’80’s — which is great because it reminds me of the machines I grew up pumping quarters into.
Description of the vending machine:
- Dixie-Narco bubble-front Pepsi machine w/ 8 selections and no LCD display
- Model number on schematic on the internal refrigerator door: F803,822,980.01
- There is another model number on the door facing the coin acceptor: A903.901.150.41
- Measurements: ~80” height x 37” width x 26” depth (approx.)
- 8-column
- circa ’87, according to wiring diagram
For more detail: Tennessee State Legislator Files Bitcoin Bill