Circuit Documentation

Summary of the Circuit

This circuit integrates a Raspberry Pi Zero W with an HC-SR04 Ultrasonic Sensor and an RTC DS3231 Real-Time Clock module. The Raspberry Pi Zero W serves as the central processing unit, controlling the ultrasonic sensor to measure distances and utilizing the RTC module to keep track of the current time. The ultrasonic sensor is powered by the Raspberry Pi and is triggered by one of its GPIO pins, while the echo pin is used to receive the signal reflected back. The RTC module is connected via I2C to the Raspberry Pi, allowing for time synchronization.

Component List

Raspberry Pi Zero W

• Description: A low-cost, compact version of the Raspberry Pi with wireless LAN and Bluetooth connectivity.
• Pins: 5V, 3V3, multiple GPIOs, Ground, CSI for camera module.
• Purpose: Acts as the main controller for the circuit, interfacing with the sensor and RTC module.

HC-SR04 Ultrasonic Sensor

• Description: A sensor that uses ultrasonic waves to measure distance.
• Pins: VCC, TRIG, ECHO, GND.
• Purpose: To measure distances by emitting ultrasonic waves and detecting the reflected signal.

RTC DS3231

• Description: A highly accurate I2C real-time clock with an integrated temperature-compensated crystal oscillator (TCXO) and crystal.
• Pins: 32K, SQW, SCL, SDA, VCC, GND.
• Purpose: To provide a real-time clock for timekeeping purposes.

Wiring Details

Raspberry Pi Zero W

• 5V connected to HC-SR04 Ultrasonic Sensor VCC
• 3V3 connected to RTC DS3231 VCC
• GPIO2 (SDA) connected to RTC DS3231 SDA
• GPIO 3 (SCL) connected to RTC DS3231 SCL
• GPIO 23 connected to HC-SR04 Ultrasonic Sensor TRIG
• GPIO 24 connected to HC-SR04 Ultrasonic Sensor ECHO
• GND connected to HC-SR04 Ultrasonic Sensor GND and RTC DS3231 GND

HC-SR04 Ultrasonic Sensor

• VCC connected to Raspberry Pi Zero W 5V
• TRIG connected to Raspberry Pi Zero W GPIO 23
• ECHO connected to Raspberry Pi Zero W GPIO 24
• GND connected to Raspberry Pi Zero W GND

RTC DS3231

• VCC connected to Raspberry Pi Zero W 3V3
• GND connected to Raspberry Pi Zero W GND
• SCL connected to Raspberry Pi Zero W GPIO 3 (SCL)
• SDA connected to Raspberry Pi Zero W GPIO2 (SDA)

Documented Code

There is no code provided for the microcontrollers in the circuit. Typically, the code would be used to initialize and control the interactions between the Raspberry Pi Zero W and the connected peripherals (HC-SR04 Ultrasonic Sensor and RTC DS3231). The code would include initializing the GPIO pins, setting up the I2C communication, and implementing the logic for triggering the ultrasonic sensor and reading the distance measurements, as well as retrieving the current time from the RTC module.