Allowing stand-alone and local control of a single led

Abstract

A telephone having key/light control logic which enables independent and dual usage of physical key/light pairs. Firmware within the telephone's key and light control logic is provided access to special tables which have definitions for each key. When a key is depressed, a feature activation code is sent uplink to notify the PBX of the user's action. In response to receipt of the feature activation code, the PBX returns a feature indication. When the telephone receives the feature indication, it scans the tables and turns on all lights for which the feature indication matches the key definition. Within the tables, an extra definition is maintained for the standalone light. This definition is downloaded by the switch at phone initialization time along with the key definitions. If the switch defines a key definition as 'local' then the user programs the definition of that key either via the phone keypad or through an application. The independent or dual usage of a light is achieved by using a special case code in the phone firmware when the lights are being lit via feature indications from the switch. If the feature indication matches the key definition for the key reserved, for example, for Mute, then the light is lit only if the key is a locally defined key. In this way, lights for local keys will always match their key definition. Conversely, if the feature indication matches the definition for the standalone light, the light next to the Mute key is lit only if the key is system defined.