What are dip switches?

Dip switches are small switches that can be found on lots of different circuit boards, from computer motherboards to engine management systems in cars to air conditioning systems. They allow engineers to turn on different operating modes by selecting different combinations of switches. These different modes may may be something simple like a diagnostic mode to something that fundamentally changing how the machine works.

They can also be found in the system boards of arcade machines. Dip switches on arcade machines allow arcade operators to things like how many credits are required to play or turning sounds on and off in attract mode. They often even allowed operators to change the gameplay, with options for how many lives players start with, when to award bonus lives and even difficulty.

Here's a pic of dip switch banks 6K and 6J on a Galaga system board, highlighted by a red border:

As you can see, they are pretty small -- too small to change with your finger tip, so people usually use a small flat screw driver or even a pen, if they're feeling lazy.

If you play games on MAME, go into the options and you will usually find dip switch settings you can change in there too.

MTW