ESP32 RTC Based Camera Using Motion Sensor

This security and surveillance system coordinates timekeeping, motion detection, and image capture using an ESP32 DevKit v1 equipped with a camera module. The circuit relies on a PIR sensor to detect physical movement in the monitored area. When triggered, the PIR sensor sends a digital signal that interacts with a switching circuit composed of a BC547 transistor and an optocoupler, which helps isolate and trigger the processing unit safely. Simultaneously, an I2C-compatible real-time clock (such as a DS3231 or DS1307) provides accurate timestamp data, ensuring that every event is logged with precise date and time information. The system status and operational messages are presented to the user via a compact 0.96-inch OLED display connected over the I2C bus. Once motion is detected and the timestamp is verified, the ESP32 activates its integrated camera to snap a digital photograph. This image file is then written directly to an external SD card via an SPI-based SD card module for later retrieval and review. Power stability is maintained throughout the circuit by an LM1117 3.3V voltage regulator, supported by filtering capacitors to manage current spikes during high-power operations like image compression and wireless transmissions.