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daisychain (bused interface) A means of connecting a number of devices to a controller, or, used as a verb, to connect by this means. A cable is connected from the controller to the nearest of the devices and then a separate cable connects the first unit to the second and the process is repeated as required. This allows a single connector on the controller to serve a variable number of devices. It also reduces cable cost and eases installation when several devices have to be connected. The IEEE-488 and SCSI interfaces are suitable for this sort of connection.

Daisychain connection is also used as a means to prioritize I/O interrupts. In this application there is active logic at the points of interconnection to ensure that the priority accorded to a device is directly related to its place in the chain. The device nearest to the controller has highest priority.