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Breaking up a CAN Frame

I Have a Frame that I am trying to brake up 

The Frame contains an Array containing:  Time stamp, 64 bit pay load, CAN ID, Type and if extended.

I Need to extract just the 64 bit pay load but am not finding a good way to do it.

The 64 bit pay load contains 2 32 bit IEEE 745 floating point numbers.

I am using the example CAN FRAME INPUT STREAM.VI with data coming from a TI. Launch pad.

It is generating all the required data 

I have tried some of the ARRAY icons ARRAY SUBSET etc without any luck.

Anyone got a good idea 

 

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  1. Are you using a NI CAN interface and NI-CAN?
  2. Do you have the devices' "secrete decoder ring"  to decode the CAN frame?

Here's an example of a CAN bus "sniffer" I write for a Toshiba Lithium Battery pack. It should give you an idea of how to do it...

 

TCanMon.png

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=== Engineer Ambiguously ===
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Thanks for the VI

The Bus is being handled by an NI-USB8502 which uses NI-XNET.

I found that I am having a little luck using the Delete From Array Icon then use the deleted output.

Next I need to split up the pay load into 2 32 bit binary sections.

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Hi John,

 


john@crane wrote:

Next I need to split up the pay load into 2 32 bit binary sections.


So the payload contains 8 bytes and you want to create 2 numbers from it.

Are those numbers integers, FXP or SGL entities? (SGL because of your other thread where you also forgot to provide useful information.)

 

You may use UnflattenFromString:

(You may also use a typedefined cluster instead of the SGL array constant…)

Best regards,
GerdW


using LV2020 on Win8.1+cRIO
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