Flash the ESP32-P4

This guide walks through setting up the ESP-IDF toolchain and flashing the SmartPot firmware onto an ESP32-P4-NANO module for the submerged vision unit.

Legacy Hardware

For flashing the original ESP32-CAM submerged unit, see the archived flash guide.

Prerequisites

• Waveshare ESP32-P4-NANO module
• OV5647 NoIR camera module with MIPI CSI flex cable
• MicroSD card (for model and calibration data)
• USB-C cable (data-capable)
• Computer with ESP-IDF installed (v5.4+ required for P4 support)

Hardware Setup

MIPI CSI Camera Connection

1. Locate the MIPI CSI connector on the P4-NANO (labeled “CAM” on the board)
2. Lift the connector latch gently
3. Insert the OV5647 NoIR flex cable with contacts facing down
4. Press the latch closed — it should click

Caution

MIPI CSI flex cables are fragile. Do not bend sharply at the connector junction. When routing inside an enclosure, use strain relief (adhesive cable clips or potting) to prevent fatigue failure from vibration. See Waterproof Enclosure for protection guidelines.

MicroSD Card

Insert a FAT32-formatted MicroSD card containing:

• species_detect.espdl — the detection model (see Train the Species Model)
• calibration.bin — camera calibration data (see Train the Species Model)

Tether Connection

Caution

Pin assignments for the tether UART on the ESP32-P4-NANO are TBD — needs hardware validation. The GPIO mapping differs from the ESP32-CAM. Do not wire the tether until pin assignments are confirmed and documented in the Submerged Unit Reference.

Install ESP-IDF

The ESP32-P4 requires ESP-IDF (not Arduino). Follow the official installation guide:

# Clone ESP-IDF (v5.4+)
mkdir -p ~/esp && cd ~/esp
git clone -b v5.4 --recursive https://github.com/espressif/esp-idf.git
cd esp-idf && ./install.sh esp32p4

# Activate the environment (add to your shell profile)
. ~/esp/esp-idf/export.sh

Verify the installation:

idf.py --version
# Should show v5.4.x or later

Build and Flash

cd firmware

# Set the target to ESP32-P4
idf.py set-target esp32p4

# Build the firmware
idf.py build

# Flash via USB-C (no FTDI adapter needed)
idf.py flash

# Monitor serial output
idf.py monitor

Tip

Unlike the ESP32-CAM, the P4-NANO has a built-in USB-C port for programming. No GPIO0-to-GND jumper, no external serial adapter, no reset button dance. Just plug in and flash.

Verify

The serial monitor (115200 baud) should show:

SmartPot Trap Unit v0.2-p4
Camera initialized: OV5647 NoIR (MIPI CSI)
Calibration loaded: focal=500.0px dist=350mm img=320x320
ESP-DL model ready
Door default: UNLOCKED
Tether UART initialized
Waiting for tether connection...

If the camera fails to initialize, verify:

1. MIPI CSI flex cable is fully seated and latch is closed
2. The OV5647 module is a NoIR variant (no IR-cut filter)
3. ESP-IDF MIPI CSI driver is enabled in sdkconfig

If the model fails to load, verify:

1. MicroSD card is FAT32-formatted and inserted
2. species_detect.espdl is at the card root
3. calibration.bin is at the card root

PlatformIO Alternative

The trap_p4 environment in platformio.ini is configured for ESP-IDF framework:

cd firmware
pio run -e trap_p4
pio run -e trap_p4 --target upload
pio device monitor -e trap_p4

Note

PlatformIO ESP32-P4 support may lag behind ESP-IDF releases. If you encounter build issues, try the native ESP-IDF toolchain first (instructions above).

Next Steps

• Load the detection model (see Train the Species Model)
• Connect to the smart buoy via tether cable (after pin validation)
• Configure keeper thresholds for your target species in species_rules[]