I think that was me....
I went FULL RETARD and...
Bugged smart guys with a problem.... before I painstakingly eliminated every possibility of it being my fault.
How it happened... (mindflowdump)
(With regard to IXXAT dongles going bad, isolated vs non-isolated, counterfeit vs genuine)
When the dongles start going they become inconsistent. Very hard to diagnose (especially) when you are using them to diagnose.
When the knock-off went... it first required USB unplug resets... more and more... then eventually quit completely to where 10 re-plugs would not bring it online. Pretty sure it died while I was operating the Dyno. Probably when something stopped suddenly. Big shoot-thru of some sort.
SubEdit -> I wonder if Terminating more aggressively would sink noise spikes and protect the device from Transients????
Now I have an genuine IXXAT giving up the ghost. Compact V2
I change the baud (reset...) see a few values pop up in DVT... glitch (frozen)... then it traps out.
Anyone reading should be thinking:
1st) His CAN termination is off
2nd) Is there even CAN traffic?
I have the dongle attached to a Dsub-9 connector populated with only CAN_HI, CAN_LO, and GND
Twisted pair for CAN, ground not twisted in
Custom cable - short run - to the 35pin Sevcon Connector
I have the loop-back installed... terminating the loop with 120ohms in one cable... (thats the Sevcon internal termination)
I have a ClearView installed in another... (replacing the loop back) where termination happens out at the ClearView (with its loop back)
I have confirmed traffic by connecting ClearView and monitoring voltage.
I have confirmed no stale data by varying the voltage and monitoring it on the bar graph
No pack voltage goes to the ClearView... only GND, 24V, CANhi, CANlo... so there is a 100.0% chance good data is on the CAN bus
I dial in the ClearView settings to view the Auto-Baud and confirm 500khz...
So... Unknown controller working... spitting out CAN to a known good ClearView... (termination should be reviewed here... hrm...)
I attach a Was-Known-Good IXXAT Compact V2...
Buss gets fouled sometimes - locks up
Sometimes a few bytes hit DVT if I cycle thru different bauds to reset the buffer in the box
Anything from No CAN light, to Solid CAN light, to blinking CAN light.
Pretty sure there are programmable loads in the IXXAT boxes... you can turn termination on and off... (Found my Fail... these are not NI CAN boxes...)
Thinking some nefarious Lukeman may have changed the settings in my tool?
I was gone for like... a month... but usually nobody plays with the dongle but me
Bah... no internal termination that can be turned on and off...
Ok - So I have two CAN networks.
One goes ClearView to Gen4 to Dongle
One goes Gen4 to Dongle
In the Gen4 to Dongle... Termination is at the Sevcon via Loopback
Termination at the Dongle is... eh... eh hem... uh... well you see boss...
Oh... Yea... eh... I see...
On the setup where the ClearView is attached... we have Termination at the Clearview, semi-short run to the Sevcon, then super short run to the Dongle
Single ended again
Anybody see how hard I failed?
This is one of the biggest take-homes you should take home from any of my blatherings...
You can develop a process..
A detailed and disciplined procedure...
You can follow it for days, weeks, months, or even years.......
Then one day something changes.
Maybe the weather
Maybe the ... position of the moon relative to your work space (almost serious here...)
And that luck suddenly runs out.
It runs out sometimes.
Best to recognize it when it does...
In my case I was running without CAN termination for EVAR... I mean for a real long time.
It just worked
Out of luck... and my good looks...
Then something changed. (du know... maybe blew out some protection diodes or something...)
Now... Termination seems mission critical.
I suspect... that when I go back in to work today... that when I plug in the DB-9 that I will pick up at Santa Cruz Electronics (with the built in Termination)... that my problems... will dissolve away.
Ok - how do we write it up?
Pfffftttt... Lessons learned
Expensive Lessons... on the importance of CAN termination.
NOw... if I go in and that termination DOES NOT get me rolling again... and I DO have another jaked Dongle... Grrrr..... That will really suck
Place your bets
I was trapped in IXXAT hell for a couple days....
Increasing battery voltage and controller current limit will result in a non linear experience