Telephone operation

Archiver

Hi everyone,

I am wanting to build a telephone screener. The idea I had was to
have a stamp answer the phone. Then use an ISD2560 chip to ask the
caller to enter the access code or hold on the line to leave a
message. If the access code was entered properly then the stamp
would ring the telephone. If the code was wrong or not entered then
the caller would be connected directly to the answering machine and
the phone would have not wrang. (My goal is to completely eliminate
all unwanted calls like telemarketers).

Now for the question. Can anyone provide me with any information on
the operation of the telephone? I have found some info on the
internet but nothing very helpful. I would appreciate any help.

Thanks
Steve