How to Build an ESP32-CAM Setup Portal Security Camera

A tiny camera that sets up its own Wi-Fi portal and can recover without rewriting code

ESP32 Security Intermediate35 minutes4 components

Updated June 12, 2026

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How to Build an ESP32-CAM Setup Portal Security Camera — For illustrative purposes only

On this page

What you'll build
Wiring diagram
Components needed
Assembly
Pin assignments
Code

What you'll build

This guide turns an ESP32-CAM into a small security camera that behaves more like a finished gadget than a loose development board. On first boot it creates its own setup Wi-Fi network, serves a browser page for your home Wi-Fi details, then joins that network so you can open the camera locally. If you need to move it to a new network, the sketch has a /reset page that clears the saved credentials and reboots back into setup mode — no USB, no code editing required.

The build uses the AI Thinker ESP32-CAM, its onboard OV2640 camera, and the built-in flash LED on GPIO 4. There is very little external wiring once the board is programmed. The guide pays particular attention to the parts that trip people up: stable 5 V power, how to enter upload mode, reading Serial Monitor, and why FLASH_LED_PIN is driven low on boot.

The result is a workshop or desk camera you can flash from Schematik, configure from your phone, and keep improving later with motion alerts, a printed enclosure, or a better mounting bracket.

What you are building

The firmware has five jobs:

on first boot (no saved credentials), start a Wi-Fi access point named ESP32-CAM-Setup and serve a configuration form at http://192.168.4.1,
save the submitted SSID and password to non-volatile storage using Preferences,
on subsequent boots, read those credentials and join the home network in station mode,
serve JPEG captures at /capture and a simple root page at /,
clear credentials and reboot when /reset is requested, returning the board to setup mode.

Holding FLASH_LED_PIN low on boot prevents an unwanted flash burst during camera initialisation. The RESET_HOLD_SECONDS constant (currently 8) is defined but not used for a long-press reset in this version; the web /reset route is the recovery path.

Upload and calibrate

There are no Wi-Fi credentials to edit before the first flash — the portal handles that at runtime. The two constants worth knowing are:

#define FLASH_LED_PIN     4
#define RESET_HOLD_SECONDS 8

FLASH_LED_PIN is held LOW immediately in setup() to prevent a flash burst on boot. RESET_HOLD_SECONDS is defined for future use; the current recovery path is the web /reset route, not a long press.

After flashing and resetting:

On your phone or laptop, join the ESP32-CAM-Setup Wi-Fi network.
Open http://192.168.4.1 and enter your home 2.4 GHz network name and password.
The board saves the credentials and reboots. Serial Monitor shows the local IP address once it connects.
Open http://<local-ip> from a device on the same network. The root page links to /capture for a single frame and /reset to wipe credentials.

If the stream is slow, the frame size is set to FRAMESIZE_VGA. Reducing it to FRAMESIZE_QVGA in configureCamera() will speed up the response on crowded networks.

Troubleshooting

Board boots into setup portal every time even after saving credentials. The Preferences key "cam-portal" may not have written. Check that the save form posted to /save successfully (Serial Monitor shows a reboot message) and that the board is not browning out mid-save due to an underpowered supply.
"Camera init failed" in Serial Monitor. Wrong board profile selected, or the camera ribbon is not fully seated. Re-select AI Thinker ESP32-CAM and reseat the ribbon.
Cannot connect to ESP32-CAM-Setup network. The board may have silently joined a previously saved network. Check Serial Monitor — if it shows a local IP, the credentials were already saved from a previous session.
/reset page returns a response but the board does not reboot. Supply voltage may be dropping during the reboot. Ensure the 5 V rail can handle the inrush on restart.
ESP32-CAM resets during capture. The camera and Wi-Fi together draw significant current. Switch from USB to a dedicated 5 V supply rated at 1 A or more.
Flash LED turns on during boot unexpectedly. An earlier sketch left GPIO 4 in an unexpected state. The current sketch drives it LOW at the start of setup() — after reflashing this should not recur.

Going further

The setup portal pattern works well for any ESP32 project that needs field-configurable credentials. Once you are comfortable with the Preferences storage and the AP/STA mode switch, you can extend the portal form to capture other settings — MQTT broker address, frame rate, or a device name — without adding any libraries.

For a version of the camera with a physical doorbell button, a passive buzzer chime, and a ring counter in the browser page, see the ESP32 Video Doorbell guide.

Wiring diagram

Loading diagram…

Components needed

Component	Type	Qty	Buy
ESP32-CAM Development Board	board	1	$0.00
Industrial USB to TTL Converter (FT232RNL)	other	1	$6.49
5V 2A Power Supply w/ 20AWG 6' MicroUSB Cable - International	other	1	$14.95
M3 x 10 Hexagonal Standoffs Mounting Kit (10 Sets)	other	1	€3.50

Supplier links, prices, and availability are shown as a guide and may change. Schematik may earn a commission from purchases made through affiliate links.

Assembly

Prepare the ESP32-CAM

Fit the OV2640 camera ribbon firmly into the ESP32-CAM socket and mount the board so the antenna is not boxed in metal.

Connect the USB serial programmer

Wire programmer 5V to ESP32-CAM 5V, GND to GND, U0R to programmer TX, and U0T to programmer RX. Link IO0 to GND only while flashing.

Flash and open Serial Monitor

Upload the sketch, remove the IO0 to GND link, press reset, and watch Serial Monitor at 115200 baud.

Join the setup portal

On first boot, connect to the camera setup Wi-Fi network, open http://192.168.4.1, and save your 2.4 GHz Wi-Fi name and password.

Power and place the camera

Move to a stable 5V supply. Use the printed local IP address from Serial Monitor or the setup page to open the private camera stream.

Pin assignments

Pin	Connection	Type
5V	esp32-cam 5V	POWER
GND	esp32-cam GND	GROUND
GPIO 3	esp32-cam U0R	UART
GPIO 1	esp32-cam U0T	UART
GPIO 0	esp32-cam IO0	DIGITAL
GPIO 4	esp32-cam FLASH_LED	DIGITAL
GPIO 0	esp32-cam XCLK	DIGITAL
GPIO 26	esp32-cam SIOD	I2C
GPIO 27	esp32-cam SIOC	I2C
GPIO 5	esp32-cam Y2	DATA
GPIO 18	esp32-cam Y3	DATA
GPIO 19	esp32-cam Y4	DATA
GPIO 21	esp32-cam Y5	DATA
GPIO 36	esp32-cam Y6	DATA
GPIO 39	esp32-cam Y7	DATA
GPIO 34	esp32-cam Y8	DATA
GPIO 35	esp32-cam Y9	DATA
GPIO 25	esp32-cam VSYNC	DATA
GPIO 23	esp32-cam HREF	DATA
GPIO 22	esp32-cam PCLK	DATA
GPIO 32	esp32-cam PWDN	DIGITAL
5V	usb-serial 5V	POWER
GND	usb-serial GND	GROUND
GPIO 3	usb-serial TX	UART
GPIO 1	usb-serial RX	UART
GPIO 0	usb-serial IO0_FLASH_LINK	DIGITAL
5V	power-supply 5V_OUT	POWER
GND	power-supply GND	GROUND

Code

Arduino C++

OpenOpen in Schematik

#include <WiFi.h>
#include <WebServer.h>
#include <Preferences.h>
#include "esp_camera.h"

#define FLASH_LED_PIN 4
#define RESET_HOLD_SECONDS 8

// AI Thinker ESP32-CAM pin map
#define PWDN_GPIO_NUM 32
#define RESET_GPIO_NUM -1
#define XCLK_GPIO_NUM 0
#define SIOD_GPIO_NUM 26
#define SIOC_GPIO_NUM 27
#define Y9_GPIO_NUM 35
#define Y8_GPIO_NUM 34
#define Y7_GPIO_NUM 39
#define Y6_GPIO_NUM 36
#define Y5_GPIO_NUM 21
#define Y4_GPIO_NUM 19
#define Y3_GPIO_NUM 18
#define Y2_GPIO_NUM 5
#define VSYNC_GPIO_NUM 25
#define HREF_GPIO_NUM 23
#define PCLK_GPIO_NUM 22

Preferences prefs;
WebServer server(80);
String ssid;
String pass;

void startSetupPortal();
void startCameraServer();

bool configureCamera() {
  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer = LEDC_TIMER_0;
  config.pin_d0 = Y2_GPIO_NUM;
  config.pin_d1 = Y3_GPIO_NUM;
  config.pin_d2 = Y4_GPIO_NUM;
  config.pin_d3 = Y5_GPIO_NUM;
  config.pin_d4 = Y6_GPIO_NUM;
  config.pin_d5 = Y7_GPIO_NUM;
  config.pin_d6 = Y8_GPIO_NUM;
  config.pin_d7 = Y9_GPIO_NUM;
  config.pin_xclk = XCLK_GPIO_NUM;
  config.pin_pclk = PCLK_GPIO_NUM;
  config.pin_vsync = VSYNC_GPIO_NUM;
  config.pin_href = HREF_GPIO_NUM;
  config.pin_sscb_sda = SIOD_GPIO_NUM;
  config.pin_sscb_scl = SIOC_GPIO_NUM;
  config.pin_pwdn = PWDN_GPIO_NUM;
  config.pin_reset = RESET_GPIO_NUM;
  config.xclk_freq_hz = 20000000;
  config.pixel_format = PIXFORMAT_JPEG;
  config.frame_size = FRAMESIZE_VGA;
  config.jpeg_quality = 12;
  config.fb_count = psramFound() ? 2 : 1;
  config.fb_location = CAMERA_FB_IN_PSRAM;
  return esp_camera_init(&config) == ESP_OK;
}

void handleRoot() {
  server.send(200, "text/html", "<h1>ESP32-CAM</h1><p><a href='/capture'>Capture frame</a></p><p><a href='/reset'>Reset Wi-Fi setup</a></p>");
}

void handleCapture() {
  camera_fb_t *fb = esp_camera_fb_get();
  if (!fb) {
    server.send(503, "text/plain", "Camera capture failed");
    return;
  }
  server.sendHeader("Content-Disposition", "inline; filename=capture.jpg");
  server.send_P(200, "image/jpeg", (const char *)fb->buf, fb->len);
  esp_camera_fb_return(fb);
}

void setup() {
  pinMode(FLASH_LED_PIN, OUTPUT);
  digitalWrite(FLASH_LED_PIN, LOW);
  Serial.begin(115200);
  delay(200);

  prefs.begin("cam-portal", false);
  ssid = prefs.getString("ssid", "");
  pass = prefs.getString("pass", "");

  if (ssid.length() == 0) {
    startSetupPortal();
    return;
  }

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid.c_str(), pass.c_str());
  Serial.print("Joining Wi-Fi");
  for (int i = 0; i < 40 && WiFi.status() != WL_CONNECTED; i++) {
    delay(250);
    Serial.print('.');
  }
  Serial.println();

  if (WiFi.status() != WL_CONNECTED || !configureCamera()) {
    startSetupPortal();
    return;
  }
  startCameraServer();
}

void startSetupPortal() {
  WiFi.mode(WIFI_AP);
  WiFi.softAP("ESP32-CAM-Setup");
  server.on("/", HTTP_GET, []() {
    server.send(200, "text/html", "<form method='post' action='/save'><label>Wi-Fi name <input name='s'></label><br><label>Password <input name='p' type='password'></label><br><button>Save</button></form>");
  });
  server.on("/save", HTTP_POST, []() {
    prefs.putString("ssid", server.arg("s"));
    prefs.putString("pass", server.arg("p"));
    server.send(200, "text/plain", "Saved. Rebooting into camera mode.");
    delay(500);
    ESP.restart();
  });
  server.begin();
  Serial.println("Setup portal: http://192.168.4.1");
}

void startCameraServer() {
  server.on("/", handleRoot);
  server.on("/capture", handleCapture);
  server.on("/reset", []() {
    prefs.clear();
    server.send(200, "text/plain", "Wi-Fi settings cleared. Rebooting.");
    delay(500);
    ESP.restart();
  });
  server.begin();
  Serial.print("Camera page: http://");
  Serial.println(WiFi.localIP());
}

void loop() {
  server.handleClient();
}

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