Connection slow error

[Hinchewortu 0]

I have to receive data via serial port from a device and I am using a FX5U with RS232 port. 

The only baud rate which seems to work is 2400, which is very low in my opinion. I have tested the serial comm on the device with a PC, same cable and it works flawlessly at 57600 baud rate.

The FX5U and device serial settings are similar.

[Gambit 326]

The FX5 works fine on higher Baudrates. 
How are you using the RS232 port. Non protocol , pre -defined protocol , Modbus ????
What is the Scan time of the PLC ?