We offer two DTMF shields for Arduino. The basic and the plus models as shown below. Chose the one that fits best your project.
|DTMF Shield BASIC||DTMF Shield PLUS|
|Best for simple DTMF detection projects.||Best for building an IVR (Interactive Voice Response).|
|Send DTMF||two-tone method||playback method|
|Audio Interface||3-pin (TRS)||4-pin Combo port (TRRS)|
|Detect Cell Ringing|
|Answer Call button|
|Play Audio into Calls|
|docs||User Manual, Forum||the basics, getting started, help|
Detect Cell Ringing: the incoming audio from a cell phone is amplified and fed into an Arduino analog port. The Arduino code will monitor the amplitude of this signal and consider the phone is ringing when the signal is above the configured threshold.
Answer Call Button: this feature emulates the button press of a headset.
Play WAV into calls: play files from the MicroSD card – requires conversion to RAW.
Easy Debug: the Basic DTMF shield requires an oscilloscope to measure signal amplitude into the board. The MICO DTMF shield has a built-in signal amplifier that lets you measure the amplitude of the input signal in a provided sample sketch.