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no CAN card installed

I have a USB-8473 high-speed CAN device setup in my machine.  When I look at this device in MAX and go to Devices and Interfaces/USB-8473 and self test the device I get a passed for this test.  I downloaded the examples file to setup a configuration for the CAN Channels and now see a Transmission Fluids and a Instrument Panel for a grouping of channels and I can see that they were associated with the examples file for each group.  When I click on one of the channels, say Clutch Pressure I get a panel with the properties associated with the channel.  However, when I click the Test Panel button I get a popup dialog box, Test Panel Error, stating "The Test Panel cannot run since no CAN ports are available.  Be sure to have at least one NI CAN card inserted into your machine".  This is strange since the 8473 card is attached to the USB port!  Any ideas?

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What examples are you talking about?

 

Remember that the 8473 has a limited functionality. It can't work with XNET or Ni-CAN Channel API, only NI-CAN Frame API will work. 

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As dkfire says, this is because USB CAN uses the Frame API not the Channel API, and therefore you cannot see channel data. The reason for this decision in our products is down to hardware limitations, the channel API requires the use of periodic objects stored on the memory of the microprocessor. The microprocessor in our USB devices are unfortunately unable to process these objects.  


For more information on the two API's available and how to use the Channel API with USB devices, please see the articles linked below.  

NI-CAN Channel and Frame API  
http://digital.ni.com/public.nsf/allkb/10A5BBC9B096A34186256F940002C659?OpenDocument  

How to use the NI-CAN Channel API with USB-CAN Hardware?  
http://digital.ni.com/public.nsf/websearch/7A7875C000F205DD862572640073B8CF?OpenDocument  

Which NI-CAN Frame API Functions does the NI USB-847x Device Support?  
http://digital.ni.com/public.nsf/allkb/E1A44077DA6C819186257288006B76D7  

CAN Frame to Channel Conversion Library User Guide 
http://digital.ni.com/manuals.nsf/websearch/247EBF8EF4661015862576D600526455 

We also have a CAN feature comparison table which may also be of use to you:

http://zone.ni.com/devzone/cda/tut/p/id/5859

 

I hope you find this helpful!

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It seems strange that NI would supply Channel APIs when they can't be used for the USB devices since everything I've done so far with CAN is with a USB device and I've even written a project that uses CAN through a USB connection in 68HC12 assembly. Even the interface into a car uses a USB connection.  And what good is the frame to channel conversion library if all we can do is use frames!  It seems like a bit of a project to test any code for the CAN VIs since so far all I've found is the CAN Device Simulator which looks like it might be a nice tool to use for developing a CAN project, but the price sure puts it out of range for the home hobbyist.  This seems like the article from one of your magazines about making a nice automotive diagnostic VI for the home hobbyist and then we found out that the Automotive Diagnostic Command Set was $1000. Nice price for a home hobbyist.

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