Arduino Based Pop Machine

A machine that turns out quite common and very capable and wondered how difficult it would be to add a key-override so you could buy drinks without having to put money in. This idea quickly ballooned into the creator’s mind, to build a full-fledged cash card system that all of us could use.

By digging through the service manual for the machine, the creator found modern protocol that coin changers and credit card readers use to interface with the machine. It has an irritating 9-bit word with an 11-bit transmission protocol. He was able to find the pinout of the port and with 110V right on the same connector. He was able to figure out that shorting Vend NO and Vend COM twice caused the machine to add a credit of $1.00. He also bought a new Arduino, an Adafruit ethernet shield, a Wiznet ethernet module, an LCD screen, and an RFID reader.

Then user scans their card, which is read via the RFID reader. The ID is sent to a piece of software running on one of my servers, which compares it to a database and retrieves the user name and their current credit amount.

Rest of the project