from fastapi import FastAPI from pymodbus.client import ModbusSerialClient import threading import time serial_port = "COM5" baud_rate = 9600 modbus_client = ModbusSerialClient(port=serial_port, baudrate=baud_rate, ) modbus_data = "0" def poll_modbus(): global modbus_data modbus_client.connect() while True: try: response = modbus_client.read_discrete_inputs(0, 1, unit=1) print(response) if not response.isError(): modbus_data = response.registers[0] print(modbus_data) except: pass threading.Thread(target=poll_modbus, daemon=True).start() app = FastAPI() @app.get("/modbus_data") async def get_modbus_data(): return {"modbus_data": modbus_data} @app.get("/") async def root(): return {"message": "Welcome to FastAPI with Modbus"} if __name__ == "__main__": import uvicorn uvicorn.run(app, host="0.0.0.0", port=12345)