Controllable annunciator using ring signal

Details Controllable annunciator using ring signal Controllable annunciator using ring signal

1987-05-21

1989-07-11

Dwyer, James L.

Telephonic communications

Call or terminal access alarm or control

At substation

379375, H04M 166

Patent

active

048478954

ABSTRACT:
This invention provides a central processing unit having read only memory for storing permanently the firmware and random access memory for storing the protocol which can be changed by user via the keyboard when need, which also has a detector for counting the ring signal inputted from the line and sending it to the CPU. When the count of the ring signal and the interval between the hang-up and dial are all met, the protocol stored in the RAM of the CPU and the control device enabled by the CPU via the output terminal send the tone signal to the ring apparatus for signaling the user.

REFERENCES:
patent: 3876836 (1975-04-01), Langan
patent: 4409439 (1983-10-01), Gumble
patent: 4459435 (1984-07-01), Foldvary et al.
patent: 4674115 (1987-06-01), Kaleita et al.

Affiliated with

Also associated with

Rating

Controllable annunciator using ring signal does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Controllable annunciator using ring signal, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Controllable annunciator using ring signal will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-443204