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Products => Test Equipment => Topic started by: klaff on May 22, 2017, 04:10:26 pm

Title: Siglent SDS12102X-E CAN decode/trigger question
Post by: klaff on May 22, 2017, 04:10:26 pm

Hi,

I'm using the CAN features, both triggering and decoding, and I'm a little confused by the setup.  I've got CANH on CH1 and CANL on CH2 and can get the functions to work with Source selected as CANH, CANL, or CANH-CANL.  CANH and CANL each have their own threshold, and that makes sense, although it may not work correctly on a system with large but acceptable common-mode noise level. The CANH-CANL choice would seem to make more sense, but there's no threshold adjustment for the difference. Does anyone know precisely what the scope is doing in that case? Experimentally, it seems to not be different than just using CANL.

There's also an odd bug in which the thresholds for CANH and CANL can't be set to greater than 0.75 V, but selecting 1x instead of 10x probe setting allows setting of a useful value (e.g. 0.34 V), and after resetting the probes to 10x the useful value is scaled correctly (e.g. 3.4 V).

I also notice that the CAN decoding doesn't work for history pages, the decoded values stay on the screen but only reflect the value of the last capture.

Thanks.

Title: Re: Siglent SDS12102X-E CAN decode/trigger question
Post by: tautech on May 22, 2017, 08:15:29 pm

Threshold bug known and you are using the current workaround, 1x probe settings.
New FW is being worked on ATM, hopefully it's not far from coming out.

Title: Re: Siglent SDS12102X-E CAN decode/trigger question
Post by: klaff on May 22, 2017, 09:35:35 pm

Thanks.  Do you know about the CANH-CANL question? I'm trying to figure out if it is not fully implemented or if I don't understand the setup correctly.

Title: Re: Siglent SDS12102X-E CAN decode/trigger question
Post by: tautech on May 22, 2017, 10:07:19 pm

Quote from: klaff on May 22, 2017, 09:35:35 pm

Thanks.  Do you know about the CANH-CANL question? I'm trying to figure out if it is not fully implemented or if I don't understand the setup correctly.

Not right now.
I did have a quick fiddle with Decode and noticed a couple of things "not quite right" and forwarded them to the factory along with other reports of apparent bugs.
I was asked by Siglent to send my test board (STB3) to member Defpom for a wider range of signals to use in his YT reviews so ATM I don't have a signal source to check Decoding until my next stock order arrives.  :(

Maybe others can chime in with their findings.

Title: Re: Siglent SDS12102X-E CAN decode/trigger question
Post by: klaff on May 23, 2017, 05:16:14 am

Thanks. I just got the scope last week and have been breaking it in. Got EasyScopeX running tonight over USB.