An interactive subscriber telephone terminal, comprising: a display screen; a plurality of temporarily definable response/data entry keys; and local control means for selectively causing the display screen and/or the response/data entry keys to be controlled by one of: remote signals transmitted to the...http://www.google.es/patents/US5615257?utm_source=gb-gplus-sharePatente US5615257 - Screen-based telephone set for interactive enhanced telephony service
Screen-based telephone set for interactive enhanced telephony service
