First logic analyzer for canbus work - Page 1
Forum section: electronics / testgear

author: rockdude14
author_rank: Newbie
timestamp: May 22, 2022, 10:40:14 pm
content: I'm a mech engineer and using an automotive canbus project as a way to brush up on both my EE and programming skills. I know these kind of posts suck but did a lot of research so hopefully you can help fill the last couple gaps and I'll have my first LA soon.Problem- Working on three canbus networks (not all at the same time) with just an arduino and canbus shield. First two networks are 33.3kbps and 500 kbps and I'm having no problems there but the last is 1000kbps and for some reason it seems like I'm getting nothing from it. I can tone out the wires with my DMM and that seems fine but now I'm stuck. Figure this is a good excuse to buy a new tool. Eventually I could imagine doing tome i2c or spi work, but nothing specific right now.Since this isnt the most demanding application I think the actual LA probably wont be the most important part but probably the software and how usable it is (especially since this isnt my area of expertise so I can focus more on my problem less on the tool). Also any features that might be handy for me that I dont even know I want yet.Currently considering (my best guess at ranking)Digilent Digital Discovery - Seems like the signal generator and integration with matlab could be really nice. I think this would probably be my top choice, but like I said I know next to nothing about this.Saleae Logic 8 bit lower hardware specs, no signal generator, but sounds like both a good company for support and nice softwareDSlogic Plus - bit cheapear but still seems plenty capable for what I needLots of options + sigrok - pretty much anything on herehttps://sigrok.org/wiki/Supported_hardware, doesnt sound as easy to use but price is really niceJust curious if given this info if there's anything I'm missing or which would be a good choice to push me towards. No specific budget, but I dont mind spending a little if its going to either save me some time or give me something I'll have a chance at growing into, currently looking around the 100-400$ range or so but if I can save some cash, that just gets to go to some other cool tool.Thanks for any advice.

author: nctnico
author_rank: Super Contributor
timestamp: May 22, 2022, 10:52:16 pm
content: Get an oscilloscope preferably with CAN protocol decoding. With a logic analyser you'll be flying blind if you can't at least see the shape of the signals. Assuming the signal waveforms are OK is often not a good idea.For CAN bus specific, you are better off buying a CAN interface with some software. I had good results with this device:http://www.can232.com/?page_id=16together with this software:https://www.wgsoft.de/can-monitor-canusb

author: rockdude14
author_rank: Newbie
timestamp: May 22, 2022, 10:59:22 pm
content: When you say oscilliscope with decoding would that be considered an MSO or are there differences between the two? Still learning all the differences.I did have the pico 2000 on the list, but the MSO version was around $550, so getting a little pricey but still might make sense.

author: nctnico
author_rank: Super Contributor
timestamp: May 22, 2022, 11:10:13 pm
content: Quote from: rockdude14 on May 22, 2022, 10:59:22 pmA regular digital storage oscilloscope (DSO) will do just fine; decoding works on the analog channels just fine. MSO means an oscilloscope has additional digital channels.

author: PaulAm
author_rank: Frequent Contributor
timestamp: May 23, 2022, 04:18:22 pm
content: You can try a Saleae clone (~ $10USD or so) with sigrok and a CAN decoder to look at stuff, although a scope is definitely useful as well.Here's a link to a CAN decoder and some other stuff that may be of interest:https://kentindell.github.io/can2