I have a communication problem between the V10/V9 and Mitsubishi QnU series CPU built-in Ethernet.

Please check the settings below:

Screen program settings:

[System Setting] > [Hardware Setting]

• Select [Model: QnU series (Built-in Ethernet)] at [Device Select].

• [Device Select] > [Target Port no.] and select appropriate port to connect.

For the V10/V9's built-in LAN port, select either [Built-in LAN(UDP)] or [Built-in LAN(TCP)].
(For the V10/V9 with an extra LAN port, [LAN2(UDP)] and [LAN2(TCP)] options are also available.
 *Protocol to use for the PLC must be correctly selected as will be described later.

For connection with the V10/V9's optional Ethernet unit (CUR-03), select [LAN unit].
  * Only UDP/IP protocol is supported.

• [PLC1 Property] > [Property] > [Target Setting] > [PLC Table] and set an IP address and a port number of the PLC.
    * Set the same IP address and Host station port No. as the PLC settings
       described in the section below.
  
  
• Select the PLC for connection from those registered on the PLC table at [PLC1 Properties] > [Target Settings] > [Connect To].
  (Valid only for 1 : 1 connection)

PLC settings:

For a CPU's built-in LAN port:

Set [PC parameter] of Mitsubishi's programming tool.