For the DTMF generator (like the Philips PCD3311C), in order to survive, now include selection between I2C or parallel data input, modem tone generating and even two octave musical note generation. A bit of music while waiting on the phone line for all those "valuable customers".
UM91214B (Tone Generator) & MT8870 (Decoder) is a good match pair unfortunately they are out of date.
But still available in some areas.The UM91214B is more than 15$ & the other is 0.6$.
The circuits are in their data sheets.
Thanks a lot to all...
Actually i wanted to control devices around 10 using 4 digit password for security purpose via wireless...
I deciede DTMF , If you say this an old technique suggest me present tech.
I am little unawareness in this case.
Thanks...
Thanks a lot to all...
Actually i wanted to control devices around 10 using 4 digit password for security purpose via wireless...
I deciede DTMF , If you say this an old technique suggest me present tech.
I am little unawareness in this case.
Thanks...
Check my PIC tutorials, you simply transmit a digital code with one PIC and the receiving PIC decodes and does what's required. It GREATLY simplifies both ends of the system, and adds much greater flexibility.