
28 Jun MPPI TROUBLESHOOTING
During execution of the PC application, the different channels in the GUI “glitch” and appear as greyed out some instants.
This is a normal behaviour, it is just the GUI main screen refreshing the data in the dashboard. The channels are not switched off or disconnected, this is just a effect of the synchronization of the data refreshing in the GUI.
One or several of the current channels appear with “Status OK” when there is no laser connected, or they appear with “Status Error” when the laser is connected.
You need to “Zero” the voltage value once your laser is connected to the MPPI (but still disabled or biased with 0 mA).
The MPPI detects the status based on some parameters, being the voltage across the laser one of them. If you “Zero” your channel, the voltage drops of the connections of your specific setup are considered in the algorithm and the status will be calculated properly.
Moreover, the measured voltage across the laser when it is enabled will have better precision.
The MPPI has been delivered with DHCP as network configuration and I need fixed/custom IP settings
You can access the network card configuration of the MPPI and change these settings following these steps:
- Connect you MPPI (preferably using directly a network cable or under a DHCP local network).
- Identify the IP of your MPPI in the PC application or in using the command “ipconfig” under “cmd” in Windows.
- Using Internet Explorer (Chrome or Firefox are not compatible with Microsoft Silverlight), access the IP of your MPPI to access the web configuration of your MPPI.
- In the left, select Network adapters, change the settings, save and restart the MPPI.
After a while, the PC application comes back to the initial “Select device” screen
The MPPI has safety measures in case the connection with the PC is lost.
This is caused by network related issues: network micro-cuts, router instabilities, poor Wifi signal…
In this case, the MPPI initiates a safe shutdown that includes:
- Ramping the lasers down to 0 mA.
- Disable the lasers (the output relay will close and anode and cathode will remain shortcut to avoid any ESD related problem).
- Disable the temperature controllers.
- Close connection handlers with the PC and reboot MPPI.
I am having connectivity issues with my MPPI. When I start the PC application, the following error or a similar one about NI System Configuration or target not being accesible appears.

This is one of the most common problems that appears when you are setting up your MPPI.
The SOM/E uses a sBRIO board from National Instruments (NI). The connection to the PC is done using proprietary packages and APIs from National Instruments that can cause different problems and compatibility issues under some circumstances.
1. The system has been working with no problem, but at some time, the error appears when the application is started.
Possible causes:
- The SOM/E (NI sbRIO) has an FPGA and a dual core processor with a RT OS. The RT OS boots in approximately 20-30 s. Sometimes, if you try to access the MPPI before this, some connectivity issues can arise.
- The system has not been properly shutdown. You must close the PC application before switching of the MPPI. When you do this, all the channels are safely disabled and the connection with the PC is properly closed.
Solution:
- Reset the MPPI (switch off, wait 30 s and switch on again) and reset your computer. Usually, if some connection has not properly closed, a reset will solve the problem.
2. I still have the same issue after following the steps in 1.
Possible causes:
- If you are connected in a local network, your Firewall or antivirus may blocked the connections.
Solution:
- First of all, please try another connection method (direct Ethernet cable or USB) to see if this is the case.
- To identify the problem you may also disable antivirus and firewall and check if the application starts without firewall.
- If this seems to be the problem, you can follow the steps from NI to include the adequate rules in the your firewall. Please take in mind that just allowing the MPPI application in the firewall may not be enough, as the connection process is done using several National Instruments APIs.
https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000P7DrSAK&l=es-ES
http://www.ni.com/product-documentation/12402/en/
3. I still have the same issue after following the steps in 1 and I´m connected using USB, so 2 does not apply.
Possible causes:
- The USB driver is incorrect or has not been properly installed.
Solution:
- First of all, connect your MPPI using USB. In Windows Device Manager, you should see the connection as “NI USB to LAN adapter” under Network Adapters category.
- If you don´t see this, you will need to uninstall the device and driver in Device Manager and reinstall the MPPI software again. Do not connect the MPPI again after uninstalling the USB drivers and before reinstalling the MPPI software again.
4. I still have the same issue after following all previous steps.
Possible causes:
- The NI drivers and APIs used for connecting the MPPI are having some compatibility issue with your PC.
Solution:
- Open NI MAX (NI Measurement and Automation Explorer) that is installed in your computer with the MPPI software. Refresh the program, this will force the computer to search for local and remote NI-compatible systems available. If your MPPI now appears in MAX, the MPPI software should work now.
- Although this case should have a minimal occurrence, some users has reported some connectivity issues after following all previous steps. After a deep study of the causes, it seems to be related to compatibility issues of some computers (usually old computers) with the several processes, APIs and drivers from NI that MPPI need to operate. Unfortunately, the best option in this case is just try another PC o a newer PC.