Open Bitcoin ATM




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


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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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    34 Discussions


    4 weeks ago

    Hey there, I know this post is sort of dated but I’m kind of needing help with the wiring. I think I have got it but I am having an issue of seeing which wires connect to what exactly. I’m having trouble reading the photos given but am trying my best but it doesn’t even turn on, maybe I wired something incorrectly. Im using the apex 7600. I might need to resolder. maybe someone could send a clear pic especially on how they connect the power adapter. its my first time using a solder and sd shield. I connected the brown apex wire to the 5v buck converter while the black apex wire to the arduino ground. I could also send a pic or video showing exactly what I did. Any help would be really great I’ve been tinkering with this for more than 10 hours but super excited about this. If you want to email me that would be cool too :-)

    1 reply

    5 years ago on Step 9

    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

    Reply 5 years ago on Step 9

    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.




    Reply 5 years ago on Step 9

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


    5 years ago on Introduction

    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


    5 years ago on Introduction

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


    5 years ago on Introduction

    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

    Reply 5 years ago on Introduction

    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).


    Reply 5 years ago on Introduction

    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).


    Reply 5 years ago on Introduction

    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.


    5 years ago on Introduction

    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

    Reply 5 years ago on Introduction

    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


    5 years ago

    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


    5 years ago on Introduction

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


    Reply 5 years ago on Introduction

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