DAQ Troubleshooting
Last updated
Last updated
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Problem: The OCT Host executable fails to launch.
Solution: Check that the AxsunOCTControl.dll and and LibUsbDotNet.dll files are present in the same directory as the OCTHost.exe application. If these libraries were inadvertently moved or deleted, reinstall OCT Host.
Problem: Fonts on the Hardware Control Tool or Image Capture Tool GUIs are rendering incorrectly and causing text to be clipped, for example:
Solution: Adjust your Windows 10 Display settings as shown:
Axsun GUI tools such as the Hardware Control Tool or the Image Capture Tool will present an error message to the user on application launch if a software dependency is missing or has not been installed correctly. Repeat the instructions in the Integrated Engine Getting Started Guide for Installing Software.
Dependencies for the AxsunOCTCapture.dll library are installed during the Image Capture Tool installation process.
Dependencies for the AxsunOCTControl_LW.dll library (and the Hardware Control Tool when configured to use AxsunOCTControl_LW.dll) are described here.
Problem: When launching the Image Capture Tool, an error states: axStartSessionPCIe Call Library Function Node in axStartSessionPCIe_wrapper.vi->Advanced Image Capture Application.vi
Solution: PCIe DAQ drivers have not been installed correctly. Repeat these instructions for installing the PCIe device drivers.
NOTE: Dependency Walker or Dependencies can be useful tools for identifying missing dependencies on Windows OS. Run one of these tools on a binary file like AxsunOCTCapture.dll to help identify if dependencies are not present in the appropriate search path due to incomplete installation.
Problem: The installAxsunPCIeDAQwd____.bat batch file will not run, or it briefly flashes a cmd prompt window and immediately closes without performing any installation as described in the Installing the PCIe Device Driver instructions.
Solution #1: You may not be logged into Windows with Administrator privileges. To overcome this, right-click on the batch file's icon and select "Run as administrator" rather than simply double-clicking on the batch file icon:
Solution #2: You may not have previously run the OCT Host installer, which includes the Axsun USB driver and creates an "Axsun OCT Devices" class hierarchy in the Device Manager.
Problem: Windows OS complains that the drivers are not digitally signed and the drivers are subsequently disabled in Device Manager after restarting the computer.
Solution: Some versions of Windows are configured to require digitally signed drivers. Change the Windows startup settings to disable Windows 10 Driver Signature Enforcement according to one of the following links, or by searching online for "disabling windows driver signature enforcement":
Problem: An Axsun DAQ or Laser device is powered-on and physically connected via USB cable, but a successful device connection is not indicated in OCT Host (or in client code based on the AxsunOCTControl API):
Solution: Check if the connected Axsun USB device is correctly listed in Device Manager as an Axsun OCT Engine in the "Axsun OCT Devices" class hierarchy (note that a USB-connected Axsun DAQ board will also be listed as Axsun OCT Engine in this list):
...If the USB device IS NOT listed as shown above, try the following until the problem is solved:
Check the physical cable connection (e.g. is the USB cable damaged or partially plugged? does the same cable work with other USB devices? does the USB port on the PC work with other USB devices?).
Cycle power to the Axsun device. Wait for it to restart and then show up in Device Manager and in OCT Host.
Uninstall and then reinstall the USB device driver according to the OCT Host installation instructions.
If none of these steps fix the problem, contact Axsun technical support.
...If the USB device IS listed in Device Manager as shown above, this indicates the problem is not likely related to the USB device driver or Axsun hardware but rather OCT Host or the operating system. Try the following until the problem is solved:
Quit and then relaunch OCT Host.
Unplug and then re-plug the USB cable connecting the Axsun device.
Turn off the Axsun device and shutdown the PC. Reboot the PC and wait for the OS to load. Launch OCT Host and then power-on the Axsun device and wait for it to successfully connect.
If none of these steps fix the problem, contact Axsun technical support.
Problem: An Axsun DAQ or Laser device is powered-on and physically connected via USB cable, a successful device connection is indicated in OCT Host, but is not indicated in the Hardware Control Tool devices list (or in client code based on the AxsunOCTControl_LW API).
Solution: The Hardware Control Tool can use either AxsunOCTControl or AxsunOCTControl_LW for USB communication with an Axsun device. If the USB-connected Axsun device is not successfully connected to the Hardware Control Tool when using AxsunOCTControl_LW, insure that the correct USB device driver is installed by following the instructions here.
Problem: An Axsun DAQ has been powered-on and physically connected via Ethernet cable for at least 30 seconds, but a successful device connection is not indicated in OCT Host or in the Hardware Control Tool (or in client code based on the AxsunOCTControl or AxsunOCTControl_LW APIs):
Solution: Check if the DAQ will respond to ICMP pings by launching a command prompt or terminal window and executing ping 192.168.10.2 (this is the static IP address of the DAQ board).
...If the ping was unsuccessful ('Request timed out.' or '100% loss' or similar message):
this indicates a problem with physical connection, with the DAQ device or its firmware, or with the network adapter configuration. Try the following until the problem is solved:
Insure any VPNs or other network routing or firewall software which might interfere with a network connection is disabled.
Check the physical cable connection (e.g. is the Ethernet cable damaged or partially plugged? does the same cable and Ethernet port on the PC work with other devices like a network router?).
Check the status of the large green LED on the corner of the DAQ board. If this LED is not steadily blinking, contact Axsun technical support.
Cycle the power to the Axsun DAQ board off and then back on via the DC power cable. Wait for the DAQ to reboot and then attempt the ping operation again about 30 seconds later.
Re-check the network adapter configuration and IP address according to the instructions.
(Windows OS) Flush your DNS by executing ipconfig /flushdns in a command prompt. Also, confirm the correct IP address for the network adapter by executing ipconfig /all to list the settings of all active network adapters.
(Windows OS) Disable and then re-enable the network adapter via its icon in the Network Connections control panel:
If none of these steps fix the problem, contact Axsun technical support.
...If the ping was successful (packets received with '0% loss'):
but the DAQ will not connect successfully in OCT Host or the Hardware Control Tool, this indicates a problem with the GUI software configuration (or AxsunOCTControl or AxsunOCTControl_LW API calls in a client application). Try the following until the problem is solved:
If using OCT Host, go to the Devices tab and confirm that the setting Scan for Network Devices is checked ON:
If using the Hardware Control Tool, go to the Miscellaneous tab and confirm that the setting Listen for Network Devices is checked ON:
Quit and then relaunch the relevant GUI tool (OCT Host or the Hardware Control Tool).
If using the AxsunOCTControl API, make sure your client code calls the StartNetworkControlInterface() method before polling for connected devices with the GetNumberOfOCTDevicesPresent() method.
If using the AxsunOCTControl_LW API, make sure your client code calls the function axNetworkInterfaceOpen() before polling for connected devices with axCountConnectedDevices().
If none of these steps fix the problem, contact Axsun technical support.
The Ethernet DAQ uses the UDP/IP protocol for transmission of digitized image data from the FGPA to the AxsunOCTCapture library (and thus the Image Capture Tool). UDP is efficient and enables real-world bandwidths in the range of 850 Mbps on a wired 1 Gbps Ethernet connection, but packet delivery is not guaranteed by the UDP protocol and therefore packet drops (data loss) are possible in some pathological circumstances. A cumulative count of dropped packets since the DAQ's last transition from Imaging-Off to Imaging-On mode can be determined using the axGetStatus() function in the AxsunOCTCapture library, or the Buffer tab on the Image Capture Tool:
The AxsunOCTCapture library has been designed to optimize the data throughput and minimize or eliminate packet loss on modern PC hardware, but OS and other 3rd-Party processes can contend for network and processor resources in a detrimental fashion.
Problem: You are experiencing Dropped Packets during image transmission from the DAQ.
Solution: Try the following steps:
Quit unrelated applications which are unnecessary to run the Axsun OCT system, especially those which are constantly accessing network resources in the background. Some applications which are known to be particularly problematic include:
Microsoft Teams (main app as well as all background daemons)
Google Chrome
Video Conferencing or Remote Desktop Software
Dropbox, OneDrive, or other cloud-based file syncing utilities
Disable or reconfigure anti-malware software, especially that which interrupts and scans incoming network traffic.
Disable your Sound Card or Sound Output Device at the device driver level. This seems unrelated and is counterintuitive, but Window OS has a strange interaction (bug?) wherein playing sounds temporarily interrupts network traffic. If you experience a burst of dropped packets when a Windows alert chime occurs, disabling the sound card is the likely solution.
In the Windows Control Panel item for your Ethernet adapter, you will see a checklist of allowed protocols. Selectively disable items which are unrelated to the Axsun OCT operation, such as Windows file/printer sharing and network discovery. Be sure to leave enabled items like IPv4 and anything related to the installed packet capture library like Npcap.
Insure your Gigabit Ethernet network adapter driver is up to date.
Your network adapter hardware may provide some configurability which can be adjusted in the Advanced Properties tab in the driver's properties dialog (via Device Manager). For recommended properties to adjust, review these recommendations:
NOTE: when the AxsunOCTControl or AxsunOCTControl_LW libraries communicate with the DAQ via Ethernet interface, this is via a TCP/IP connection where packet delivery is guaranteed by the protocol and therefore the low-bandwidth command and control messages cannot be dropped during transmission.
