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REVIEW - Rigol DS2072 - First Impressions of the DS2000 series from Rigol
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Mark_O:

--- Quote from: Teneyes on May 06, 2014, 06:41:16 pm ---To do the testing I want to create a specific message,
but I did not have any 'CAN' bus devices to test and that would show a complete message to test with,
so I created my own messages that I can vary parameters (voltages, timing, data, and errors ) and be correct.
I needed to create the CRC for the complete message also.
I did research and tried different software , but no program generated the Correct 15 bit 'CAN' bus CRC.
 
So I went back to basics
and manually formed the CRC for the message I used in Testing
After 4 mistakes, and slow working here is my long division for the CAN bus CRC

I hope you are amused

--- End quote ---

My hat is definitely off to you.   :-+  I've been working with numerous CAN protocols on a daily basis, for about a decade now (J1939, ISO-14229, CANOpen, ISO-15765, etc.), and I've never taken the time to do that by hand.  Of course, I've always had chips available in my product designs that did that work for me.  So I could afford to be 'lazy'.  :) 

In the old days, they were outboard CAN chips (Microchip, Intel, NXP), but now all the MCUs in the embedded space have one or two CAN channels built-in.  Most of the work gets done in the protocol stack sitting on top of the physical transport layer.
Teneyes:

--- Quote from: Mark_O on May 07, 2014, 09:41:54 am ---In theory, that may be interesting.  But in practice, I don't think it's either necessary or reasonable for a diagnostic test device to decode bus traffic that will never occur.
I'd have to dig back into the Bosch defining specs for CAN 2.0 to find all the nitty-gritty details of the state-transitions that occur after a bus-error, but I can tell you for sure that recovery is never instantaneous, and no properly operating CAN transmitter will ever start sending the next frame as soon as you'd like the Rigol to be able to decode it.

--- End quote ---
Thanks  Mark_O, for the feedback ,

As for "will never occur."   but I would say "SHOULD never occur"

I can see Rigol having a test setup of a  CAN Network and running tests.
Then programming the DSO to display the communication traffic.    I suspect extra code was put into the program  to delay the searching for Start of Next Frame in order to duplicate the Norm.
My philosophy is more to look for the odd occurrences. ( stray cat, hardware bug, geeky chick)

I got eNote that Rigol Marketing is sending a report over to R&D
Teneyes:
Here's an Odd Occurance
Mark_O:

--- Quote from: Teneyes on May 07, 2014, 10:24:26 am ---As for "will never occur."   but I would say "SHOULD never occur"

--- End quote ---

Yes, you are correct.  I'd have to agree with you on that distinction.
hans:
Has anyone had any problems with a Rigol DS1074Z(-S) scope not booting up from time to time?

I believe I am running the SP5 firmware (which it came with, not sure if there is a new version 3.0 out yet) , and from time to time the scope just sits there and doesn't boot up. No lights from the front panel light up, and the screen just says Rigol.
If I repower the scope it works fine.

It has happened with both installed and uninstalled options key (still on trial period for a few hours).
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