Re: ckt for caller id...hardware
Try a search on Yahoo. I searched on '"caller id" schematic' and
came up with lots of information on this subject.
http://www.zilog.com/docs/dsp/caller_id.pdf gives a sample circuit
and information for building a caller id using a Zilog chip.
The caller id hardware seems to be just a 1200 baud modem and a
display circuit - when you subscribe to the caller-id service, the
telephone company sends the date, time, and telephone number that is