Circuit Documentation

Summary

The circuit in question appears to be a complex system involving motor control, audio processing, and wireless communication capabilities. It includes stepper motors controlled by A4988 stepper motor driver carriers, an ESP32-CAM module for wireless camera functionality, an INMP441 microphone for audio input, a MAX98375 audio amplifier for driving a loudspeaker, and an Arduino Nano for general-purpose I/O and interfacing. The system is powered by a 5V battery and includes limit switches for position sensing and a servo motor for additional movement control.

Component List

A4988 Stepper Motor Driver Carrier

• Description: A module for driving bipolar stepper motors.
• Pins: ENABLE, MS1, MS2, MS3, RESET, SLEEP, STEP, DIR, GND, VCC, 1B, 1A, 2A, 2B, VMOT

Stepper Motor (Bipolar)

• Description: A bipolar stepper motor for precision movement.
• Pins: D, B, C, A

ESP32 - CAM

• Description: An ESP32-based module with camera functionality.
• Pins: 5V, GND, IO12, IO13, IO15, IO14, IO2, IO4, VOT, VOR, VCC, IO0, IO16, 3V3

INMP441 FRONT MIC

• Description: A digital I2S output microphone.
• Pins: L/R, WS, SCK, SD, VDD, GND

Loudspeaker

• Description: An audio output device.
• Pins: pin1, pin2

5v Battery

• Description: A power source for the circuit.
• Pins: positive, negative

Rocker Switch

• Description: A switch to control power flow.
• Pins: 1, 2

MAX98375

• Description: An audio amplifier for driving speakers.
• Pins: LRC, BLCK, DIN, GAIN, SD, GND, VIN

FTDI Programmer

• Description: A USB to serial converter for programming.
• Pins: DTR, RX, TX, VCC, CTS, GND

Limit Switch

• Description: A switch that is actuated by the motion of a machine part or presence of an object.
• Pins: C, NO, NC

Arduino Nano

• Description: A small, complete, and breadboard-friendly board based on the ATmega328.
• Pins: D1/TX, D0/RX, RESET, GND, D2, D3, D4, D5, D6, D7, D8, D9, D10, D11/MOSI, D12/MISO, VIN, 5V, A7, A6, A5, A4, A3, A2, A1, A0, AREF, 3V3, D13/SCK

ESP32 Devkit V1

• Description: An ESP32-based development board.
• Pins: 3V3, GND, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, RX0, TX0, D22, D23, EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, VIN

Servo

• Description: A rotary actuator or linear actuator that allows for precise control of angular or linear position.
• Pins: GND, VCC, PWM

Wiring Details

A4988 Stepper Motor Driver Carrier

• ENABLE: Not connected
• MS1, MS2, MS3: Not connected (microstepping configuration pins)
• RESET: Connected to SLEEP
• SLEEP: Connected to RESET
• STEP: Connected to Arduino Nano D6 or D8 (depending on the instance)
• DIR: Connected to Arduino Nano D5 or D7 (depending on the instance)
• GND: Connected to system ground
• VCC: Connected to 5V through Rocker Switch
• 1B, 1A, 2A, 2B: Connected to corresponding pins on Stepper Motor (Bipolar)
• VMOT: Not connected (motor power supply)

Stepper Motor (Bipolar)

• D, B, C, A: Connected to corresponding pins on A4988 Stepper Motor Driver Carrier

ESP32 - CAM

• 5V: Connected to 5V power supply
• GND: Connected to system ground
• IO12, IO13, IO15, IO14, IO2, IO4: Not connected (general purpose I/O)
• VOT: Connected to FTDI Programmer RX
• VOR: Connected to FTDI Programmer TX
• VCC: Not connected (3.3V power supply)
• IO0, IO16: Not connected (general purpose I/O)
• 3V3: Not connected (3.3V power output)

INMP441 FRONT MIC

• L/R: Connected to 5V power supply
• WS: Connected to ESP32 Devkit V1 D25
• SCK: Connected to ESP32 Devkit V1 D33
• SD: Connected to ESP32 Devkit V1 D32
• VDD: Connected to 5V power supply
• GND: Connected to system ground

Loudspeaker

• pin1, pin2: Connected to MAX98375 audio amplifier output

5v Battery

• positive: Connected to Rocker Switch pin 1
• negative: Connected to system ground

Rocker Switch

• 1: Connected to 5V battery positive
• 2: Connected to system 5V power rail

MAX98375

• LRC: Connected to ESP32 Devkit V1 D14
• BLCK: Connected to ESP32 Devkit V1 D27
• DIN: Connected to ESP32 Devkit V1 D26
• GAIN: Connected to 5V power supply
• SD: Not connected (shutdown control)
• GND: Connected to system ground
• VIN: Connected to 5V power supply

FTDI Programmer

• DTR: Not connected
• RX: Connected to ESP32 - CAM VOT
• TX: Connected to ESP32 - CAM VOR
• VCC: Connected to 5V power supply
• CTS: Not connected
• GND: Connected to system ground

Limit Switch

• C: Connected to system ground
• NO: Connected to Arduino Nano D2 or D3 (depending on the instance)
• NC: Not connected

Arduino Nano

• D1/TX: Connected to ESP32 Devkit V1 TX0
• D0/RX: Connected to ESP32 Devkit V1 RX0
• RESET, AREF, 3V3: Not connected
• GND: Connected to system ground
• D2, D3: Connected to Limit Switch NO (depending on the instance)
• D5, D6, D7, D8: Connected to A4988 Stepper Motor Driver Carrier DIR and STEP (depending on the instance)
• D9: Connected to Servo PWM
• D10, D11/MOSI, D12/MISO, D13/SCK: Not connected (SPI interface)
• VIN: Connected to 5V power supply
• 5V: Connected to system 5V power rail
• A7, A6, A5, A4, A3, A2, A1, A0: Not connected (analog inputs)

ESP32 Devkit V1

• 3V3, VP, VN, EN, D34, D35, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, D22, D23, D12, D13: Not connected
• GND: Connected to system ground
• RX0: Connected to Arduino Nano D0/RX
• TX0: Connected to Arduino Nano D1/TX
• D25: Connected to INMP441 FRONT MIC WS
• D33: Connected to INMP441 FRONT MIC SCK
• D32: Connected to INMP441 FRONT MIC SD
• D26: Connected to MAX98375 DIN
• D27: Connected to MAX98375 BLCK
• D14: Connected to MAX98375 LRC
• VIN: Connected to 5V power supply

Servo

• GND: Connected to system ground
• VCC: Connected to 5V power supply
• PWM: Connected to Arduino Nano D9

Documented Code

ESP32 - CAM Code (Instance ID: b48c5a91-c825-4549-af62-cc3ca2f782df)

#include <WebServer.h>
#include <WiFi.h>
#include <esp32cam.h>

const char* WIFI_SSID = "Your SSID";
const char* WIFI_PASS = "Your Password";

WebServer server(80);

static auto loRes = esp32cam::Resolution::find(320, 240);
static auto midRes =