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Receive net_ctrl Packet from FlightGear

Receive net_ctrl packet from FlightGear

  • Receive net_ctrl Packet from FlightGear block

Aerospace Blockset / Animation / Flight Simulator Interfaces


The Receive net_ctrl Packet from FlightGear block receives a network control and environment data packet, net_ctrl, from the simulation of a Simulink® model in the FlightGear simulator, or from a FlightGear session. This data packet is compatible with a particular version of FlightGear flight simulator. This block supports all signals supported by the FlightGear net_ctrl data packet. The block arranges the signals into multiple groups. The block inserts zeros for packet values that are part of inactive signal groups.

The Aerospace Blockset™ product supports FlightGear versions starting from v2.6. If you are using a FlightGear version older than 2.6, the model displays a notification from the Simulink Upgrade Advisor. Consider using the Upgrade Advisor to upgrade your FlightGear version. For more information, see Supported FlightGear Versions.

If you run a model that contains this block in Rapid Accelerator mode, the block produces zeros (0s) and it does not produce deployable code. In Accelerator mode, the block works as expected.

For details on signals and signal groups, see Output.



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Controls information from FlightGear, returned as a 744-by-1 vector.

Data Types: uint8

Received FlightGear packet size, specified as a scalar.

  • 0, if no data is received

  • Size of the packet (744) in bytes.


This port is enabled by the Enable received flag port check box.

Data Types: double


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Enter a valid IP address as a dot-decimal string. This IP address must be the address of the computer from which FlightGear is run, for example,

You can also use a MATLAB expression that returns a valid IP address as a character vector. If FlightGear is run on the local computer, leave the default value of (localhost).

To determine the source IP address, you can use one of several techniques, such as:

  • Use for the local computer (localhost).

  • Ping another computer from a Windows® cmd.exe (or Linux® shell) prompt:

    C:\> ping andyspc
    Pinging andyspc [] with 32 bytes of data:
    Reply from bytes=32 time=30ms TTL=253
    Reply from bytes=32 time=20ms TTL=253
    Reply from bytes=32 time=20ms TTL=253
    Reply from bytes=32 time=20ms TTL=253
    Ping statistics for
        Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
    Approximate round trip times in milli-seconds:
        Minimum = 20ms, Maximum =  30ms, Average =  22ms
  • On a Windows machine, type ipconfig and use the returned IP address:

    Windows IP Configuration
    Ethernet adapter Local Area Connection:
            Connection-specific DNS Suffix  . :
            IP Address. . . . . . . . . . . . :
            Subnet Mask . . . . . . . . . . . :
            Default Gateway . . . . . . . . . :

Programmatic Use

Block Parameter: ReceiveAddress
Type: character vector
Values: scalar
Default: ''

UDP port that the block accepts data from. The sender sends data to the port specified in this parameter. This value must match the Origin port parameter of the Generate Run Script block. It must be a unique port number that no other application on the computer uses. The site,, lists commonly known UDP port numbers. To identify UDP port numbers already in use on your computer, type:

netstat -a -p UDP

Programmatic Use

Block Parameter: ReceivePort
Type: character vector
Values: scalar
Default: '5505'

Specify the sample time (-1 for inherited).

Programmatic Use

Block Parameter: SampleTime
Type: character vector
Values: scalar
Default: '1/30'

Enable a received flag output port. Use this check box to determine if a FlightGear network packet has been received.


Selecting this check box enables the Rx bytes port.

Programmatic Use

Block Parameter: packetFlag
Type: character vector
Values:'off' | 'on'
Default: 'off'

Version History

Introduced in R2012a