Description
This audio recording and playback module is based around the ISD1820 chip, specifically designed for the task. The ISD1820 can record multiple audio clips and store it in internal non-volatile memory for later playback. The playback can be controlled by onboard pushbuttons or via microcontroller. The module also features a “Feed Through” mode which can pass microphone input directly to the speaker and continuous playback mode, where the recordings are played endlessly, making this useful in a variety of projects…. from a friendly voice notification that your lawn sprinklers finished running, an interactive Halloween prop, or the foundation of a PA system in your secret volcano lair – the possibilities are endless!
To use the module, simply connect a small 8 ohm speaker to the SP1 connector and supply 3-4.5VDC to the board. Holding the REC button will record, and releasing the button will store it. Pressing PLAYE will play the next audio clip in que. Holding PLAYL will play until the button is released. Shorting the P-E jumper will continuously play as long as there is power. Shorting the F-T jumper will feed the microphone input directly to the speaker.
The total duration of recording is dependent on the sample rate, which can be configured by changing a single onboard resistor. By default, the device is configured for a balance of recording duration and sound quality, with approximately 10 seconds of recording time at a 4KHz sample rate. Maximum recording time is 20 seconds at 2KHz.