Drink

Pre-History

One of Computer Science House's longest-running projects (and the one that receives the most outside attention) is our networked drink machine. Some might ask, "Why would you want to put a drink machine on the network?" Normally the appropriate answer to this question would be "Why not?", but in this case there's actually a much more interesting story.

The original idea was simple: Obtain a regular drink machine and place it on floor. However, the company that holds an exclusive vending-machine contract with RIT complained that we were threatening their rights by operating our own independent machine. In a flash of inspiration, the drink machine was hooked up to the computer systems and made to take payment in "credits" over the network. This neatly dodged the complaint, because the modified device was much closer to a high-tech group refrigerator than a vending machine.

Drink Today

Whether due to electronics failure, better designs, or the donation of a newer machine, Drink has been reincarnated several times over the past 20 years. Most notably, in Fall of the year 2000, several House members decided to give the Drink hardware a major overhaul. The new system would not only be more robust and reliable, but it was also an opportunity to test out some newer devices that might be used for future projects.

In this case, we decided on the Dallas Semiconductor TINI and One-Wire-Net technologies. The TINI is a microcontroller designed for networking that has ethernet, serial, parallel, and One-Wire interfaces built-in. One-Wire-Net is a technology that allows you to address various electronic devices (switches, temperature sensors, etc.) on a single data/power line, using a 64-bit unique ID. Since the TINI's native language is a dialect of Java, all of the current Drink software is written in Java. The hardware is all based on One-Wire devices, including a few One-Wire switches and a temperature sensor for each drink slot.