Electronic Status Multiplexer, Discriminator and Timer for Multiple Devices
Original Publication Date: 1981-Apr-01
Included in the Prior Art Database: 2005-Feb-11
A significant increase in packaging efficiency is realized with this arrangement wherein functions accomplished in one of a number of devices that are multiplexed on a controller, and which present status in a polling mode, are transferred from the device to the controller. An example of this is a telephone line pack on an electronic exchange serviced by a controller. The line pack provides to the controller an indication of the telephone being either on-hook or off-hook. These on-hook and off-hook indications are timed for validity before being sent to the controller as an interrupt. False on-hooks and off-hooks are ignored, dial pulses are timed and not sent in flashing indications, and flashes are differentiated from "solid" on-hooks.