SLA-based routing for EAI middleware

A psychograph, of a type employing a movable indicator to designate indicia on a principal part of the device such as a board, can be constructed so that the indicator will cause a switch to close each time it points to or otherwise designates an indicia. A circuit is used to provide an output in the form of a signal capable of being stored or used by a computer, an electronic typewriter or the like when a switch is closed for a pedetermined time interval. Normally the board or similar part of the device will carry a plurality of indicia and a separate switch will be associated with each so that signals corresponding to all of the indicia can be obtained.