I think I CAN, I think I CAN... Topic is solved

[Pete9008]

No problem. Hoping to modify the GVRET code to save settings to Flash rather than EEPROM (as my board doesn't have one) this evening so working on it anyway.

Not sure the nothing for bossa is an issue, I am slightly concerned by the compile warning you also seem to have though - what is that complaining about?

Edit - just seen your latest post, looks like you're missing a library, let me have a look on mine.

[Pete9008]

I have a directory called can_common in my Arduino libraries, downloaded from here https://github.com/collin80/can_common. Are you missing it?

[Gregski]

Bad news, mine works fine. Erased it to blank and reprogrammed over the native port no problem.

Guessing it might be a Windows driver issue. Long shot but it might be worth trying it on a different PC USB port (it sometimes re-installs the USB driver)??

OH my lord after a little due_can-master (good library) swap for due_can (bad library) duplicate libraries it COMPILED on the PC !!!!

and just like that we are GVRETing...

[Pete9008]

So do you have a verdict on all the different CAN tools?

[Pete9008]

That's interesting, you don't get warnings about initialising the SDcard, does your board have a card on it?

[Gregski]

So do you have a verdict on all the different CAN tools?

not yet, I opened a Tech Support case for that black box aka the Microchip as I really want one of them darn things to work, you can follow it's status here: Sending commands using APGDT002 CAN BUS ANALYZER TOOL is not working and I am planning on testing the pink one with the Chevy Volt first gen DC-DC Converter as I believe it only requires a single CAN command instead of two, and I am pretty sure reading that Arber Kramar used that very CANalyst-II gizmo to control his, more as the news develops

I also returned this white one cause it had a horrible UI and all the documentation was in Chinese

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[Gregski]

and now we can make a connection in SaavyCAN, so progress

and we can read the CAN messages from the Chevy Volt first gen onboard charger

and we can send frames successfully using the Frame Sender in SaavyCAN

and we can confirm with a frame Capture that the first message is being sent every 30 milliseconds and the second one every 500 milliseconds

[Gregski]

That's interesting, you don't get warnings about initialising the SDcard, does your board have a card on it?

no it does not

[Gregski]

and here I confirm with a multimeter that indeed my trusty ol' lead acid battery is charging at 13.3 volts cause it drops to 12.5 when not charging


man I really like this Chevy Volt first gen charger, you can test with just the 12 volt battery and not get dead

[Gregski]

a nice overview of Saavy CAN features

[Pete9008]

Good find!

I like the look of those candlelight based CAN dongles, unfortunately I can't find stock anywhere.

[Gregski]

So I just heard back from Microchip Tech Support, the black box thingie regarding their device not working and us not being able to successfully send two back to back CAN messages using it to our Chevy Volt first gen onboard charger, and here's their response:

"Thanks for contacting Microchip Technical Support Team.

We checked the back-to-back transmit scenario and it is working perfectly."

in all fairness they did ask for a bit info...

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[TheSilverBuick]

Oof, I'm just starting to dabble in Arduino coding, and its like learning Greek to me. I'm reading these posts carefully. Thanks for plowing through the garbage to find the gems!

My GS450H transmission and inverter should arrive today. Tracking says its in my city as of last night.

[Gregski]

Oof, I'm just starting to dabble in Arduino coding, and its like learning Greek to me. I'm reading these posts carefully. Thanks for plowing through the garbage to find the gems!

My GS450H transmission and inverter should arrive today. Tracking says its in my city as of last night.

Thank you, and exciting times, I hope it's not Freight Shipping or they will expect a loading dock and a fork lift, good times!

[TheSilverBuick]

It IS freight shipping, and its being delivered to my work's warehouse! Then I'll have them plop it on my utility trailer for the drive home. Good times indeed! Now if it'll quit trying to snow I'll bein good shape.

[Gregski]

Just so you don't think I'm Mr. One n Done here I am having a go at the first gen Chevy Volt DC-DC Converter once again with the CANalyst-II

if you enjoy a fun read: I bought a Chevy Volt Gen1 DC-DC Converter - Now What?

the DC-DC Converter only requires one command to dance, so I thought this one ought to do it and that's how Mr. Kramar beat it into submission on LEAFDRIVEBLOG Ampera/Volt DCDC or APU , but no dice for The Greg

CAN ID is 01 D4

Length is 2

Msg is A0 B2 send every 100ms (B2= 14 volt output)

OR

Msg is A0 AF send every 100ms (AF= 13.8 volt output)

A0 means Start

send 00 to Stop


Pinout Info
Pin 2 (second top left) CAN Low
Pin 3 (third top left) CAN High
Pin 5 (last one top right) Ignition (so to battery positive)
Pin 10 (last one bottom right) Accessory (so to battery positive)

[arber333]

In all fairness you need to play with canalyst some to get communication going. Also termination resistor configuration is important.
I got best results when i opened a bridge between can1 and can2...

[collin80]

Sorry the EVTV board came un-programmed. They shouldn't have sent it like that. Over at savvycan.com there is a binary "updater" which actually just flashes precompiled firmware to the board -> https://www.savvycan.com/GVRETupdate.zip you can use that on basically any Arduino Due based board but as has already been mentioned, the compiled version does expect EEPROM which the Due did not have unless you got the EVTVDue that they sell which does have EEPROM on it.

And, I am aware that perhaps getting all the tools working and getting SavvyCAN connected might not all be the simplest thing ever. Compiling it all yourself is probably quite the adventure. It's tough for me to get a good baseline of where all the pinch points are because I can compile it all in my sleep at this point. But, even I get frustrated sometimes when trying to get various devices hooked up and working. I obviously have a lot of EVTV boards but I also use PeakCAN and Kvaser tools, I have the Microchip black box thing too. I have lots of CAN adapters, the PeakCAN and Kvaser are the easiest to use but the most expensive too. Really, for me the coolest one is either an EVTV ESP32 or the related Macchina A0 - both of which can connect to SavvyCAN over wifi. The A0 is especially cool in a car where you can slap it onto an OBDII port and away you go.

And, SavvyCAN is probably quite the mountain to climb because it started out as a tool for me (and a way to learn QT programming) and just kind of evolved over the course of years into having everything including the kitchen sink. There's probably like 4 ways to send CAN traffic for instance. You can use the fuzzing window, the frame sending window, you can write scripts in the script window, you can replay captured traffic. Some of them overlap but everything exists because me or someone else wanted to do something it didn't do yet. I wish I had more time to work on all the CAN tools but recently I just haven't been able to. Still, there is some progress. Be sure to check the "continuous" build if you want all the newest toys. It's automatically compiled for all three operating systems supported. Technically people compile SavvyCAN for Raspberry Pi too. But, I don't have compiled binaries for that.

[arber333]

Pinout Info
Pin 2 (second top left) CAN Low
Pin 3 (third top left) CAN High
Pin 5 (last one top right) Ignition (so to battery positive)
Pin 10 (last one bottome right) Accessory (so to battery positive)

Sorry i missed this...
Pin 5 is ignition and also signal for dcdc to wake up
Pin 10 is actually an output. That one becomes live when you provide ignition. I think it is used to turn the cooling fan on.

[Gregski]

Pinout Info
Pin 2 (second top left) CAN Low
Pin 3 (third top left) CAN High
Pin 5 (last one top right) Ignition (so to battery positive)
Pin 10 (last one bottome right) Accessory (so to battery positive)

Sorry i missed this...
Pin 5 is ignition and also signal for dcdc to wake up
Pin 10 is actually an output. That one becomes live when you provide ignition. I think it is used to turn the cooling fan on.

so are you saying we don't need to worry about ie connect Pin 10 to get the converter to convert?

[arber333]

Pinout Info
Pin 2 (second top left) CAN Low
Pin 3 (third top left) CAN High
Pin 5 (last one top right) Ignition (so to battery positive)
Pin 10 (last one bottome right) Accessory (so to battery positive)

Sorry i missed this...
Pin 5 is ignition and also signal for dcdc to wake up
Pin 10 is actually an output. That one becomes live when you provide ignition. I think it is used to turn the cooling fan on.

so are you saying we don't need to worry about ie connect Pin 10 to get the converter to convert?

No that one will work by itself. You only need CANH, CANL and Enable signal. You can use aux contact to run some indication LED so you are aware it is working...
Also i belive CAN is not terminated here. You have CAN input and CAN output lines. So if DCDC does not work reliably you might put 120R across second pair of CAN wires.

[Gregski]

No that one will work by itself. You only need CANH, CANL and Enable signal. You can use aux contact to run some indication LED so you are aware it is working...
Also i belive CAN is not terminated here. You have CAN input and CAN output lines. So if DCDC does not work reliably you might put 120R across second pair of CAN wires.

Thank you so much I really appreciate all your help as does the entire forum I'm sure. Would it be safe to assume termination is fine if we can capture ie read CAN traffic just fine, or would these CAN analyzer tools still read unterminated CAN bus traffic?

[Pete9008]

The ideal is to have a termination at each end but as long as there is a termination somewhere you should be fine on a small network (few m of cable). Too many terminations reduce the signal level, possibly to the point where messages aren't received (but that would need quite a few extra terminations).

If you find a network is really sensitive to terminations there are probably other problems (such as high electrical noise) too.

In general if you are connecting to an existing network (e.g. to debug it) don't add a terminator on the dongle and keep the cables as short as possible. If you are creating a new network with the dongle at one end then add a termination on the dongle.

[arber333]

Would it be safe to assume termination is fine if we can capture ie read CAN traffic just fine, or would these CAN analyzer tools still read unterminated CAN bus traffic?

Yes in general you should be fine if Canalyst is blinking its leds. That means it is receiving CAN traffic. Can you post a screenshot of your send/receive screen? I dont have that DCDC with me anymore, but i can still help...

EDIT: that got me thinking... when you post ID into Canalyst you have to make it in 4 byte length for "standard" length (not extended).
So for ID 0x1D4 you would put it like 00 00 01 D4. Try it...
Msg repeats in 100ms intervals. Example from my AC compressor...

[Gregski]

The ideal is to have a termination at each end but as long as there is a termination somewhere you should be fine on a small network (few m of cable). Too many terminations reduce the signal level, possibly to the point where messages aren't received (but that would need quite a few extra terminations).

If you find a network is really sensitive to terminations there are probably other problems (such as high electrical noise) too.

In general if you are connecting to an existing network (e.g. to debug it) don't add a terminator on the dongle and keep the cables as short as possible. If you are creating a new network with the dongle at one end then add a termination on the dongle.

thank you, great tips