15-11-2010, 05:17 PM
i suggest you to read
http://eet.etec.wwu.edu/wanl2/project/do...iption.pdf
may be Dtmf Decoder 1610 Am a simple one to use as
http://eet.etec.wwu.edu/wanl2/project/do...iption.pdf
may be Dtmf Decoder 1610 Am a simple one to use as