Open Bitcoin ATM




Introduction: Open Bitcoin ATM

The world's first completely open-source Bitcoin ATM for Education and Experimentation. for more information.


Step 1: Fabricate Box and Faceplate

Out of a piece of 12″x12″ aluminum sheet metal, cut two rectangles and drill six rivet holes and four holes to attach the bill acceptor.

Cut aluminum angle into two 11 1/2″ lengths.

For each aluminum angle, drill and tap two holes; drill three faceplate rivet holes.

Rivet the two aluminum angles to each side of the faceplate. Allow room (about 1/8″) to overlap with the front of the box to create flush surface; make sure aluminum angles are positioned to lie flush on the inside of box.

Drill four holes through the box that exactly align with tapped holes in aluminum angle.  (tip: if using acrylic, set drill to reverse, and gently apply pressure to prevent cracking).

Measure 16″ leads, solder  one end to barrel plug and other end to J2 connectors.  Attach barrel plug to back of box. Tape leads to base of box.

Step 2: Attach Bill Acceptor and Printer

Position printer in faceplate and attach using bracket provided.

Position bill acceptor and attach using four screws, washers and nuts.

Step 3: Provision Arduino

Download and install Arduino environment from here.

Download openbitcoin.ino from here

Attach Arduino Uno to computer USB port.

Upload openbitcoin.ino to Arduino Uno. for more information.

Step 4: Attach Resistor and Leads

Solder resistor and leads to SD shield as shown (note updated circuit diagram with pull up resistor)

Step 5: Attach SD Shield and Components

Attach SD shield to Arduino Uno.

Cover back of Arduino Uno with insulating tape.

Attach 5V power supply to back of faceplate (high strength velcro works well).

Attach Arduino/SD shield to back of faceplate with (high strength velcro).

Connect J2 connectors.

Step 6: Create QR Codes

Create a few dozen private keys at

Convert private keys to 176 x 176 pixel QR codes (sample pictured above).

Convert QR codes to thermal printer format. Sample QR code in thermal printer format:  BTC_4.btc (see for more information)

Here’s a hack that makes this process a snap:

Here’s a wallet that can read the QR code:

Step 7: Provision SD Card

Copy logo.oba to root directory of SD card. (file is here

Name QR code files sequentially, then copy to root directory of SD card.

Step 8: Configure Bill Acceptor

Print the a configuration card at the end of the Apex 7000 manual

Using a dark marker, fill in the ovals on the configuration card.

Hold the reset button down for at least ten seconds.

When the lights on the front of the acceptor blink, feed the configuration card (pictured above) into the acceptor bill slot.

Acceptor will reject the card.

Acceptor will blink rapidly if successfully configured.

Step 9: Watch the Magic!

Load up the Bitcoin addresses created in step six, stand back and watch the magic!

For more information and updates see:

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    32 Discussions

    Couldn't you just take oout the money and do it again for endless bitcoin

    So you would need to have a fixed BTC<->USD exchange rate. Not easily able to change it without resetting the whole thing and using new QR codes, right?

    2 replies

    Two ways to handle exchange rates:

    1) charge a reasonable conversion rate buffer

    2) datestamp the BTC with future dates and adjust the amount of BTC in the wallet as the rates change (this requires small change in the arduino program)

    Neither option requires resetting with new QR codes.



    I don't quite understand option 2. How would one go about doing this? Could you explain it further?

    Couldn't I just re-feed the same bill in over and over? Its a good idea, but I see why its only for education xD

    hello can i purchase this unit for a thesis project prototype can you ship it on the phillipines

    Has anyone built this? I have had problems with the dollar bill interfacing with the Arduino. The unit never delivers pulses. It acts wierd (finds pulses and crashes) if I make the resistor a PULL UP resistor. Nothing happens if it is a pull down resistor. Is the diagram correct?

    3 replies

    While the photo is accurate there was an error in circuit diagram ver 1.5. This is fixed in diagram ver 1.6.0. Note: pull up resistor is shown; removed violet connection to pin 3 (this will eventually be needed to turn off bill acceptor when BTC inventory is depleted).

    While the photo is accurate there was an error in circuit diagram ver 1.5. This is fixed in diagram ver 1.6.0. Note: pull up resistor is shown; removed violet connection to pin 3 (this will eventually be needed to turn off bill acceptor when BTC inventory is depleted).

    are you using the right bill acceptor?

    you should probably use the 12 volt pulse, however there are may may more like 120v single price, executive, 24v MDB, etc.

    so would this be able to recognize different bills? like you're using a $1 in this, but could it also accept $20 bills?

    1 reply

    I was looking on their website and the qr code assigner has a form you fill out to tell it what to accept, long-story-short the bills it will accept are completely customizable

    Hey would you have any interest in designing a similar device for a special education setting? I need something to assign currency to a credit card that can be swiped in exchange for goods. willing to compensate generously as it is very important to my school. Let me know

    are you using the Pyramid technologies "phoenix" thermal printer?

    the bill validator he is using, the apex 7000, is used in many commerical machines, so it will be able to detect counterfeit currency

    Please inform everyone that this is a proof-of-concept prototype and not meant for actual public use. There's no security for the currency inside it.

    1 reply

    you cuold probably get a cheap "coffee inns" brand quarter changer from ebay for less than 100, use that as cabinet, it also come with a bill acceptor, just rip the quarter dispensing guts out and replace the cheap lock with a better one.

    You could also replace your stackerless style validator with a stacker, that is, one with a bill box, and get the lockable bill box for more security.

    the downsides of a stacker is that they can only hold 200-1000 bills depending on what size box you get, are generally more expensive, and are bulkier.