How to Hacka A Coffee Machine

[zbeng]

At work we got new coffee machines. The supplier is the Dutch company Douwe Etters. It immediately became apparent that the coffee was not up to spec compared with our former supplier. Complaints did not result in better coffee, so I decided to try to do something about the weak coffee with froth (foam) on top of it. After all, everybody knows that foam should be on top of beer, not on coffee! On the plus side, the coffee is free.

The machine

Our new machines are from Wittenborg, a Danish manufacturer of vending machines. It is an FB7100, featuring a plethora of beverages. Of course the most important is the freshly brewed coffee. When selected, a small amount of ground coffee is put on a filter and water is applied. After a little while the resulting coffee is led to a valve and dispensed. Other beverages (chocolate etc.) are made by adding water to powder.

The crash hack

A software bug can be used to let the machine crash. When this happens, the "whipper" is not activated but the coffee already brewed is dumped in the eagerly waiting cup. This is the procedure:

1. Place cup.

2. Press the coffeepot button (see photo). Display sez: two cups or something similar.

3. Select extra strength (optional).

4. Press "coffee (black)".

5. Now remove cup. The machine goes through its brewing cycle, the progress bar in the display showing its progress.

6. The whipper starts whirring, but no coffee appears.

7. Replace the cup. After about half a minute the display blanks, then briefly shows total dispensed beverages.

8. Now a little tune is played, twice. During the second time the coffee slowly is dispensed into your cup. With no foam!

The menu hack

Incredibly, after I discovered this hack I found a similar hack on i-hacked.com involving a Coke machine! In any case, the crash hack was too troublesome to be exploited on a regular basis. So when I observed a menu appearing when the door (front) of the machine was opened to refill coffee and powder, I tried to get into the menu without using a key. This proved to be shockingly easy, thanks to a incredibly stupid design flaw. The "door open" switch, used to tell the software to enter the "menu" mode, is a long way from the lock. To activate the switch, all you have to do is pull the upper left corner of the door towards you. See the arrow on the photo. About an inch (2-3 cm) should be sufficient. Now the procedure is as follows:

1. Pull the corner. The displays shows a selection.

2. Press button "4" (see photo). Now you're in the menu.

3. Release corner.

4. Use "up" and "down" (1 and 2) to navigate to the Operator menu, then press OK. Don't use the Technician menu. You can seriously fuck up the machine with that.

5. Each beverage has its own setup. Go to the "Coffee, black" entry.

6. Now select the "Powder" entry. The buttons change to "-", "+", "->" and "OK". Place the cursor under the number to be edited with "->" and press "+" or "-" to change it. Adjust the number from 006600 (6.6 g) to something stronger. I set it to 009600 (almost 10 grams), which is much better. When finished press "OK". The setting of this value is buggy, sometimes the wrong numbers change. Oh well...

7. Set "Whipper 5" and "Whipper 5 speed" to 000000. I'm absolutely clueless as what these values stand for. Maybe they're seconds. But since we don't want foam on our coffee, zero is fine.

8. Now press "ESC" (4) to return to the beverage selection. Do your thing with other beverages as needed. You will find that these have different settings, like milk, sugar and powder.

9. Other fun settings include beverage pricing, which is not applicable to my situation as there is no coin safe in my machine, contrary to the one on the photo.

10. Press "ESC" until the menu disappears and the display says "<<<INITIALIZING>>>".

11. Done!

I could not find a way to actually change the beverages. Maybe there is a menu setting for that, it could also be pre-programmed into the machine. The Technician menu only concerns the pulps, valves and heaters in the machine. Don't mess with its settings, but the some of the tests could be fun.

When I told a colleague about it he blabbed it to a representative of Douwe Etters. He didn't believe it, so my colleague asked me to demonstrate. Rep: "But you're damaging the machine!" Me: "No, I'm hacking it!". My colleague almost shat his pants.