from pymodbus.client import ModbusSerialClient
client = ModbusSerialClient(
port="COM3",
baudrate=9600,
parity="N",
stopbits=1,
bytesize=8,
timeout=1,
)
if not client.connect():
raise SystemExit("連不上序列埠，請檢查 COM 編號")
result = client.read_holding_registers(address=0, count=2, device_id=1)
if result.isError():
print("讀取失敗：", result)
else:
print("暫存器：", result.registers)
client.close()