Beginner Qs: Vending Build Process

After the latest news of a tech company in Wisconsin partnering with Biohax to enable injectable access/vending access transcoders, a few colleagues and I would like to do a similar use case in our technology lab. After reading through 50 or so threads in the form, I have built out the following process but wanted to ask a few questions to fill in the blanks:

1.) Confirm use case + technical requirements

? - We are looking to do a vending experience either by partnering with a company or by customizing our own vending machine (as we already have with our own native app).

Can someone please provide more details around what sort of technical specs will need to be ironed out prior to moving forward? I would assume that we would either use the xEM transcoder for it’s writable UID, or the xNT/FlexNT for its 32 bit password protection feature…

2.) Purchase transponder
+ This will be determined by use case, as well as preferred fit/form factor.

3.) Confirm professional to help with piercing
+ Partners map available within DT website

4.) Write specific ID on to chip, reflecting user ID to facilitate access/purchase

? - I assume that either the EM Access Controller or the PN532 would be needed. Any other details and/or information available on implementation/testing?

Thanks to everyone in this community and I’ll apologize ahead of time if I missed any articles that flat our answer my questions above.

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It all really depends on what you want to do… I mean, if this is a one-off in a controlled environment, and you don’t need to build a whole backend for managing payment etc. then I would look into using the PN532 with your own custom antenna winding (to get batter performance with the xNT)… wire that into an Arduino … or use a Raspberry Pi with ACR122U (which does pretty well with the xNT already) that you can also connect to an external network for management purposes… and then interface some I/O pins with the vending machine’s “acceptor/validator” in some way to allow the vend to proceed after successful scan.

If this is a business idea, then I would need to know more about the concept before proceeding… PM me and I can help consult on the idea.

Thanks Amal.

This is not a business idea, more of a proof of concept for us to show off in our lab. It would be nice if we could fully integrate payments into the project, but obviously it’s a bit early for that.

I believe we may be looking to include some sort of access validation into the room itself, but I will follow up within this thread if we move forward with that requirement as well.

Thanks again.


I think payments could be done easily if you used a credit system where people bought credits which were stored in your own database… then chips were used to debit the credits. They could then top-up credits using some external method like paypal or stripe.

How about post your project updates here! I’d love to follow along and give tips… learn about how you converted your vending machine, etc. I can probably even donate some implants to the cause… or maybe you guys could arrange a “chipping party” for the space?

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The more i think about it, you will probably need to go around the bill validator and kind of build your own emulator to talk to the vending machine itself… that way you can set prices on various things you want to vend and debit the credit account appropriately.

Hey Amal,

Thanks for the thorough response. It looks like this system will only be used by our team during presentations within our lab, so I don’t think that the validator/credit system would be necessary for this particular project, but thanks for thinking through it. (It sounds like we’re already having a lot of trouble with the specific vending company we work with, and they even noted that other companies/people have made these requests, and that they are holding firm on “opening up” their system.)

All of this being said, I do have a clarifying question in regards to your initial response, specifically:

or use a Raspberry Pi with ACR122U (which does pretty well with the xNT already)

Are you stating that the xNT could work with a Rasberry Pi, or we would need to go with the ACR122U to do so?

Thanks Amal.


No problem… Basically I know very little about vending machines but I did some research years ago that lead me to believe there is a standard protocol for communicating data between the bill validator and the vending machine control system… that’s where I would focus… or by removing the control system completely and inserting your own “brain” into it… it would be difficult… you’d have to deal with power electronics of course… switching large currents and controlling vending motors and getting position sensor data and position switch data from the mechanical components within the vending machine… but it would give the highest reward.

The Pi is just a computer… it has no reader built int… so you would need to interface one. You could use the I/O pins and tie in the PN532, but doing so would be difficult compared to simply plugging in an ACR122U and loading the drivers for Linux.

Sooo did it work? :stuck_out_tongue_winking_eye:

Wow, Ryu, I didn’t know you were a necromancer (nice hat by the way :arrow_heading_down: )

I do hope you get an answer though