DIALING RESTRICTION SYSTEM FOR LOBBY DOORPHONE DEVICE

摘要

PURPOSE: To reduce man-hours of error check relating to the input of restriction information by restricting dialing by means of part of digits of a call number so as to suppress restriction to be stored for dialing restriction. ;CONSTITUTION: When a call number '1023' is depressed by a call dial 10 of a lobby doorphone device 1, a number is sent to a memory 11 and stored therein for each depression of the call dial 10. The call number, '1023' stored in the memory 11 is given to a transmitter 14. A restricted digit value '0' stored in an address in the memory 11 designated by a signal of a restricted digit from a memory 12 is outputted to a comparator 13. The comparator 13 compares a signal of a restricted value '5' received from the memory 12 with the restricted digit value '0' and gives a level 1 to the transmitter 14 as a comparison signal 20 when they are coincident. When dissident, '0' is given to the transmitter 14 as the comparison signal 20. The transmitter 14 dials the signal '1023' received from the memory 11 when the value of the comparison signal 20 is '1'.;COPYRIGHT: (C)1996,JPO