[Python] Python pymodbus can't read Mitsubishi Parameters

I have to read 1 parameter from my Mitsubishi Melservo J4, more specifically it is a MR-J4-40A-RJ. I can actually read parameters from a program called QModMaster. The settings for the connection are these:

Settings image 1

Settings image 2

Summarized are:

• Modbus mode: RTU
• Slave addr: 1
• Scan rate: 1000 ms
• Function code: Read Holding Registers (0x03)
• Start Address: 2103 Hex
• Nuber of registers: 2
• Serial device: COM
• Serial port: 7
• Baud: 115200
• Data Bits: 8
• Stop Bits: 2
• Parity: None
• RTS: Enable

My python code is this, and is not working because it goes in timeout before getting some data:

from pymodbus.client import ModbusSerialClient as ModbusClient
from pymodbus.payload import BinaryPayloadDecoder
from pymodbus.constants import Endian
from pymodbus.exceptions import ModbusIOException

# Create Modbus client instance
client = ModbusClient(
method='rtu',
port='COM7',
baudrate=115200,
parity='N',
stopbits=2,
bytesize=8,
timeout=1,
rtscts=True
)

# Connect to the serial port
connection = client.connect()
if connection:
print("Connected to the Modbus server")
else:
print("Failed to connect to the Modbus server")

# Register address and number of registers to read
register_address = 0x2103 # 2103h in hexadecimal
num_registers = 2

# Reading the registers
try:
response = client.read_holding_registers(register_address, num_registers, unit=1)
if not isinstance(response, ModbusIOException):
# Decode the response
decoder = BinaryPayloadDecoder.fromRegisters(response.registers, byteorder=Endian.Big, wordorder=Endian.Big)
parameter_value = decoder.decode_32bit_int()
print(f"Parameter PC03 value: {parameter_value}")
else:
print(f"Error reading registers: {response}")
except Exception as e:
print(f"Exception: {e}")

# Close the client
client.close()


And i get this error from the "response": Error reading registers: Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 4 bytes (0 received)

From the documentation this is the 2103h parameter: Parameter Image

I hope i was clear, ask any question i will give further info.

Thanks.

I tried my python code, i was expecting at least some byte, but i'm getting 0 bytes.

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