A simple voice recorder for Arduino using an SD card and an electret microphone amplifier circuit.
Independent of any third-party libraries.
| SD | Nano |
|---|---|
| D0 (DO) | D12 (MISO) |
| VSS | GND |
| CLK | D13 (SCK) |
| VDD | 5V or 3V3 |
| CMD (DI) | D11 (MOSI) |
| D3 (CS) | D10 (SS) |
WARNING: SD cards are not designed for 5V; I have been using 5V anyways and everything seems fine, but beware that there is a significant risk of immediate or premature failure when not using a buffer circuit.
SD pin D3 is the chip select pin. It can be set manually in PIN_SS.
| Mic | Nano |
|---|---|
| VCC | 5V |
| GND | GND |
| Out | A0 |
Out defaults to A0 (AdcChannel0), but can be set manually in ADC_CHANNEL.
| Mode | Unmodified | No voltage regulator | No TTL module or voltage regulator |
|---|---|---|---|
| Waiting | ~10mA | ~5.8mA | ~6μA |
| Recording | ~30mA | ~25.1mA | ~25mA |