CDCAM

An ESP32P4-based CDBUS (RS-485) Camera.

Protocol

CDCAM is an open-source serial camera that communicates over an RS485 interface.

• Default baud rate: 115200 bps
• Maximum speed: 50 Mbps
• Default address: 0xfe

The underlying protocol is CDBUS, with the following frame format:
src, dst, len, [payload], crc_l, crc_h

Each frame includes a 3-byte header, a variable-length payload, and a 2-byte CRC (identical to Modbus CRC).
For more information on the CDBUS protocol, please refer to:

• https://cdbus.org

The payload is encoded using the CDNET protocol. For detailed information, please refer to:

• https://github.com/dukelec/cdnet
• https://github.com/dukelec/cdnet/wiki/CDNET-Intro-and-Demo

GUI Tool

CDBUS GUI Tool: https://github.com/dukelec/cdbus_gui

Default sensor: OV5647.

Hardware

Schematic: cdcam_v4.0.pdf

Build Instructions

Based on IDF v6.0-beta1, run source esp-idf/export.sh, then execute src/idf_patchs/patch_all.sh once.
After that, enter the src directory, run idf.py set-target esp32p4 (only required the first time), and then execute idf.py build.

Firmware can be upgraded by:

• Using the CDBUS GUI tool to perform RS-485 IAP with the HEX file in the build directory.
• Running tests/ble_ota.py for OTA upgrade (or OTA via UDP).
• Via the USB debug port.

After reboot, CD-ESP will automatically switch to the new firmware.