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Setting Up Free-D Systems



This document discusses a more detailed description of the Free-D protocol and its setup process in Aximmetry. 
NOTE: Aximmetry supports the D1 messages of the Free-D specification.

What is Free-D?

Free-D is a protocol that can be used to transfer positional, rotational, zoom, and focus data of cameras or tracking systems. Which data is sent depends on the tracking system's configuration or the camera type. PTZ cameras that provide tracking data usually use the Free-D protocol.

Which Communication Protocol is Needed to Use Free-D?

To use Free-D you must have a live connection between your device and your PC.

The communication can be via

  • UDP/IP protocol
  • RS232 protocol
  • RS485 protocol

Since RS232 and RS485 protocols are rarely used nowadays for Free-D, we will proceed with the UDP/IP protocol.
NOTE: Aximmetry supports analog communication protocols (RS232 and RS485) for Free-D.

Using UDP/IP Protocol

Each tracking system that supports Free-D through UDP has an ethernet port. You can connect the device directly to your PC via an ethernet port or you can connect it into a LAN. You can use any network for this purpose, but we strongly recommend using a dedicated LAN with fixed IP addresses. This helps that the messages arrive with minimal latency and minimizes the chance of port collision.
NOTE: PTZ cameras usually have a fixed IP address by factory default.
NOTE: Port collisions can prevent the camera/tracking system from successfully providing Free-D tracking data to your computer.

On your tracking system's control unit/web UI, you must set the destination IP address where the device will send the Free-D data. You will also have to set the UDP port as well.

Setting Up Free-D on Devices

Mandatory Values

On the tracking device, you will have to set up 2 parameters:

  • IP address - with subnet mask as well.
  • UDP port number.

NOTE: There might be cases when more parameters must be set. Please review your tracking system's manual carefully to learn if there are any additional parameters to set.

Setting Up the UDP Port Number

Most tracking devices have a default UDP port number. We recommend using such default ports to avoid port collision.

For more about UDP ports please take a look at Troubleshooting.

Optional Values

If you have more than one camera in use at a time, then these can use the same UDP or COM port without collision because you can define a Camera ID for each camera in the camera's Web UI or the tracking system's control unit. The camera ID allows Aximmetry to identify which tracking data stream belongs to which camera.
NOTE: Some PTZ cameras do not support specifying the Camera ID. You must define a dedicated UDP port for each camera in these cases.

Setting Up Free-D in Aximmetry

When launching Aximmetry click on the Manage Devices... button on the Startup Configuration window to configure your devices:

NOTE: You can also access the Manage Devices... menu from within Aximmetry Composer. Just navigate on the menu bar to Edit / Manage Devices...

You can find Free-D in the Camera Tracking group:

NOTE: You can also find the Free-D protocol in the Zoom Device group because standalone Zoom Devices could also use Free-D.

Click on the Add... button. A new window named "Add Free-D Channel" will appear:

You can choose between COM and UDP ports, but we recommend choosing UDP when available. UDP is the default choice in Aximmetry.

Using UDP Port

In Aximmetry UDP is the default communication mode in Free-D settings.


You can specify a network adapter where the data will come from. This is not mandatory just an option to avoid port collisions from different VLANs.
When you choose -any- Aximmetry listens to the specified UDP port on all available networks.

UDP Port

You must set the same UDP port you specified in the tracking device.

Join Multicast Group

There can be cases when you need to send the Free-D data to several targets. For example, when using a multi-machine configuration for an LED wall production, where multiple PCs render the content displayed on one or more LED walls. In this case, you must configure a multicast group and align the group's IP address here to broadcast the Free-D data to every PC on the network.

NOTE: You can also send the Free-D packages to the Broadcast address of the subnetwork.

Camera ID

Here you can set the ID of the camera in which Free-D data will be received.
The Camera ID is a numerical value, that starts from 0 to 255 
NOTE: The apellation "Camera ID" is a historious apellation in Free-D protocol. Now it also means the tracking device ID as well.
NOTE: you will have to set up a new Free-D device in case you are using another camera with the same port and a different ID.

Using COM Port

What is a COM port?

COM (communication port) is the original, yet still common, name of the serial port interface on PC-compatible computers. It can refer not only to physical ports but also to emulated ports, such as ports created by Bluetooth or USB adapters.
Several protocols are using COM ports, like

  • RS232
  • RS422
  • RS485

If you want to use COM port you must switch to COM.

COM Port

You can select the port of the RS232, RS422, or RS485 device you are using.


Here you can set the speed of your connection. The value is in bps (bits per second).

Camera ID

Here you can set the ID of the camera in which subchannel the Free-D data will be received.
The Camera ID is a numerical value, that starts from 0 to 255
NOTE: The apellation "Camera ID" is a historious apellation in Free-D protocol. Now it also means the tracking device ID as well.
NOTE: you will have to set up a new Free-D device in case you are using another camera with the same port and a different ID.

After completing the setup process of your Free-D device, you can proceed to test it in Aximmetry.


What if the Device Doesn't Communicate?

Several things can cause a communication failure. Here is a checklist to resolve the most common causes:

  • Check if the ethernet connection physically exists and if the wires are not damaged.
  • Check if the ports are uplinked. You can see the green and yellow LED blinking next to the connector. Please note that some connectors don't have any LEDs.
  • Check if both the PC and the device have an IP address and are on the same VLAN. Check if they can communicate with a Ping command via the Command Prompt. Alternatively, you can use the "arp -a" command to list all the available devices on the network.
  • Check if the target IP address, the UDP port, and the CAM ID (optionally) are set correctly in the Device.
  • Check if the UDP port is permitted on the PC's firewall. 
  • Check if the UDP port and the CAM ID (optionally) are set up correctly in Aximmetry.
  • Check if there is no other program actively using the same port, as specified for the Free-D

What is a UDP Port?

A User Datagram Protocol port is an internetworking software abstraction, not a physical thing like a USB port.
Each device needs an IP address (all different from each other) and a port to communicate through for network communication. There are many ports in use in a simple home network because many protocols have their own officially dedicated ports (e.g. HTTP has 80, and 81. HTTPS has 443. FTP has 20 and 21, etc). 
So when you set up the UDP port you will use for Free-D we recommend using the factory default UDP port number the Free-D device comes with to avoid collisions with other ports that may be in use. 

Permit a Port on Windows Firewall

Windows Firewall is a network security application. Its main purpose is to block ports to prevent illegal penetrations from the Internet. Although some general ports are open (TCP, SSL, SNMP, FTP, etc...), you will have to open your Free-D ports manually by adding an exception to the Firewall.

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