Auxy Wiring Guide

Complete wiring reference for the Phase 1 prototype

System Diagram

How all four components connect together.

TP4056 USB-C Charger B+ B- OUT+ OUT- USB-C IN LiPo Battery 3.7V 500mAh + - red (+) black (-) ESP32-CAM AI-Thinker Module OV2640 CAM Top row: 5V GND IO13 IO15 IO14 IO12 Bottom row: 3V3 IO16 IO0 GND UOR UOT OUT+ → 3V3 OUT- → GND INMP441 I2S Digital Microphone VDD GND SCK WS SD L/R 3.3V power Ground Clock signal Word select Audio data out GND = left ch L/R → GND What we did: 1. Soldered battery (red/black) wires to TP4056 B+/B- pads 2. Soldered jumper wires to TP4056 OUT+/OUT- pads 3. Connected OUT+ → ESP32 3V3 pin (not 5V — LiPo is 3.7V) 4. Connected OUT- → ESP32 GND pin 5. Camera ribbon: gold contacts face the board, clipped in 6. Firmware flashed via USB-to-serial (TXD→UOR, RXD→UOT, IO0→GND for flash mode) 3 4 1
Power (red)
Ground (black)
Clock (orange)
Word Select (yellow)
Data (green)

Connection 1: Battery + Charger

Battery → TP4056 (Soldered)

The LiPo battery wires are soldered directly to the TP4056 charging board pads.

Battery WireTP4056 PadNotes
Red (+)B+Solder to pad — JST connector doesn't fit
Black (-)B-Solder to pad
Polarity matters! Red to B+, black to B-. Reversing this can fry the ESP32-CAM (we learned this the hard way).
LED indicators: Red = charging, Blue = fully charged. Both on = loose connection.

Connection 2: Charger → ESP32-CAM

TP4056 → ESP32-CAM (Soldered jumper wires)

Jumper wires are soldered to the TP4056 OUT pads, then plugged into the ESP32-CAM pins.

TP4056 PadESP32-CAM PinNotes
OUT+3V3Use 3.3V, NOT 5V — LiPo outputs ~3.7V
OUT-GNDAny GND pin works
Why 3V3 not 5V? The LiPo battery outputs 3.0-4.2V. The 5V pin's voltage regulator needs >4.5V input. Feeding 3.7V to the 3.3V pin works because it bypasses the regulator and the ESP32 runs on 3.3V natively.

Connection 3: Camera

OV2640 Camera Module → ESP32-CAM

The camera connects via a ribbon cable to the white connector on the ESP32-CAM board.

  • Lift the brown/black clip on the connector (gently pull up)
  • Slide the ribbon cable in — gold contacts face the board (down)
  • Push the clip back down to lock it in place
Do NOT insert a microSD card while using GPIO 13, 14, 15 for the microphone — these pins are shared with the SD card slot.

Connection 4: Microphone

INMP441 → ESP32-CAM (Jumper wires via breadboard)

The INMP441 is a digital I2S microphone. It needs 5 wires to the ESP32-CAM plus one self-connection.

INMP441 PinWire ColorESP32-CAM PinPurpose
VDD Red 3V3 Power (shared via breadboard rail)
GND Black GND Ground (shared via breadboard rail)
SCK Orange IO14 Clock — ESP32 sends timing pulses
WS Yellow IO15 Word Select — tells mic when to send data
SD Green IO13 Serial Data — actual audio signal
L/R Black GND Tied to GND = left channel (just a setting)
Sharing 3V3: Since 3V3 is already used for power, use a breadboard — run 3V3 to the + rail, then connect both the TP4056 OUT+ and the mic VDD to that rail.

Flashing Firmware

USB-to-Serial → ESP32-CAM (Temporary for programming)

Only needed when uploading new firmware. Disconnect battery power first or use the USB-to-serial for data only (GND + TXD + RXD, no 5V).

USB-to-SerialESP32-CAM
5V5V (only if not using battery)
GNDGND
TXDUOR (GPIO 3)
RXDUOT (GPIO 1)

To enter flash mode: Connect IO0 → GND, then press reset or re-power the board.

To run normally: Remove the IO0 → GND wire, then press reset.

Auxy — Built by Iliiaz Akhmedov