DIP switch
From Wikipedia, the free encyclopedia
A DIP switch is a manual electric switch that is packaged in a group in a standard dual in-line package (DIP) (the whole package unit may also be referred to as a DIP switch in the singular). This type of switch is designed to be used on a printed circuit board along with other electronic components and is commonly used to customize the behavior of an electronic device for specific situations. They were extensively used in older ISA PC cards to select IRQs and memory addresses.
DIP switches often come in packages of seven or eight. Seven switches can be used for standard ASCII characters and offers up to 128 total combinations, while eight is the size of one computer byte and has a total of 256 combinations.
DIP switches are an alternative to jumper blocks. Their main advantages are that they are quicker to change and there are no parts to lose, although jumper blocks are more often used due to lower cost.
DIP switches were also often used on arcade games in the 1980s and early 1990s to store settings, before the advent of cheaper, battery-backed RAM and were very commonly used to set security codes on garage door openers as well as on some early cordless phones. This design, which used up to twelve switches in a group, was used to avoid interference from other nearby door opener remotes or other devices. Current garage door openers use rolling code systems for better security.
These type of switches were used on early video cards for early computers to facilitate compatibility with other video standards. For example, CGA cards allowed for MDA compatibility.
DIP switches are still used in few of today's eletronics such as some computer parts.

