From 65a4ae643a00cda0f0a515d4c2fb7a60f0c88874 Mon Sep 17 00:00:00 2001
From: r4 <r4@nobrain.org>
Date: Mon, 11 Apr 2022 19:31:02 +0200
Subject: [PATCH] add readme

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+# Arduino Spy Bug
+
+A simple voice recorder for Arduino using an SD card and an electret microphone amplifier circuit.
+
+Independent of any 3rd party libraries like (unless delayed recording is used).
+
+## Wiring (also documented in spybug/spybug.ino)
+### SD Card Wiring
+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`.
+
+### Microphone Wiring (MAX9814 w/ electret microphone)
+Mic      | Nano
+---------|------------
+VCC      |  5V
+GND      |  GND
+Out      |  A0
+
+Out defaults to A0 (AdcChannel0), but can be set manually in `ADC_CHANNEL`.