A hardware + firmware prototype developed during my internship at Zebra Technologies. The system uses a Raspberry Pi Pico W to generate a 24V trigger signal for an industrial camera, while displaying status (such as trigger frequency) on a 16x2 LCD. Triggers can be issued over UART (RS232-to-serial cable) and the design is intended to support Wi-Fi control via the Pico W.

• Pico W outputs a 3.3V control signal.
• An MC33078P op-amp stage level-shifts to a 24V trigger for the camera.
• A 24V to 5V converter powers the Pico W and LCD.
• A 16x2 HD44780-compatible LCD displays runtime information.
• UART control is implemented in firmware; Wi-Fi triggering can be added using the Pico W network stack.

• Raspberry Pi Pico W
• 24V to 5V DC-DC converter
• MC33078P op-amp level-shift stage
• 16x2 HD44780-compatible LCD
• RS232-to-serial pin cable (UART control)
• 24V industrial camera trigger input

• src/SerialCommunication.py: UART receive loop + LCD output + trigger pin toggle example.
• src/CustomChar.py: LCD custom character demo.
• src/gpio_lcd.py: GPIO-based LCD driver (4-bit mode).
• src/lcd_api.py: LCD command API.
• TriggerCircuit.png: circuit schematic/diagram.
• Images/: project photos.

Circuit	View 1	View 2	View 3

• UART0 TX: GP12
• UART0 RX: GP13
• UART settings: 9600 baud, 8 data bits, no parity, 2 stop bits, inverted TX/RX
• LCD RS: GP11
• LCD E: GP10
• LCD D4: GP18
• LCD D5: GP19
• LCD D6: GP20
• LCD D7: GP21
• Trigger output example: GP0 (toggled when the string LED is received)

1. Flash MicroPython onto the Pico W.
2. Copy the files in src/ to the Pico W filesystem.
3. Run SerialCommunication.py (or rename it to main.py for auto-start).
4. Connect the UART and LCD according to the pin map above.
5. Send UART commands; received text is shown on the LCD. Sending LED toggles the output pin for triggering.

• The UART is configured with inverted TX/RX to match RS232-level signaling. Use an appropriate RS232-to-TTL interface.
• The 24V trigger domain should share a common ground with the Pico W and be properly isolated if required by the camera.
• Wi-Fi triggering can be added using MicroPython networking on the Pico W (e.g., sockets or HTTP endpoints).