Can bus monitor with avt

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Vampyre
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Can bus monitor with avt

Post by Vampyre »

How hard would it be to build a basic monitor for the Can bus, I just want to see the traffic and get some data from it for now. I'm putting a ctsv dash and electronics package in a 86 fiero. The dash won't shut up about airbag or traction control. Eventually I want to build an arduino setup to send the signal that those 2 modules are present. For now I just want to get data for button presses and other random info.
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antus
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Re: Can bus monitor with avt

Post by antus »

Its not terribly hard, its a well documented protocol, and you could probably base it on some bits of the code in pcmhammer to init the avt and start pulling data. Would need to adapt it to the can frame format. You would also need to add some kind of filtering. The can bus is fast and full pass through can easily overwhelm anything but the very fastest pc code. The latest 'user manual' (developer guide i'd call it) is available at http://www.avt-hq.com/download.htm#AVT-852

Also look at the "script files for the AVT-84x" they have there, I think they might also do what you want out of the box with their hexterm app. Just open the dwn files in notepad to see what they do, adjust the filter or other settings if need be with information from the user manual.
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
Vampyre
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Re: Can bus monitor with avt

Post by Vampyre »

Thanks antus I'm only hooking up 2 or 3 modules at a time, so hoping that won't over whelm system

I tried act hex term and it doesn't have option for 33.3k baud
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Gatecrasher
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Re: Can bus monitor with avt

Post by Gatecrasher »

Which generation CTS-V? I'm messing with an XTS uplevel cluster right now, and I figured out how to shut all those messages off. I'll bet yours uses the same messages if it's a gen 2.

I'm interested in hearing more about your project in general. It sounds pretty interesting.
Vampyre
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Re: Can bus monitor with avt

Post by Vampyre »

09 electronics first year of the 2nd gen, fiero is getting an ls4. Ill be using most of the ctsv electronics to run the lighting and interior systems
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Gatecrasher
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Re: Can bus monitor with avt

Post by Gatecrasher »

See if this works.

Airbag system status. Set to repeat with 2 sec frequency.
10324058 00 00 09 CF 00 00

Airbag indicators. Send once to turn off lights.
10330058 73 F3 73 00 00 00

Vehicle stability status. Send once to turn off lights.
10240040 80 02 88 01 FF 7D 00 04

Does AVT have a J2534 driver? I've done almost all of my work with the free DrewTech bus tool. It works with anything that has a J2534 driver. It's got a few rough edges, but in general it's really good.

If you're looking for steering wheel control input, those are probably on a dedicated LIN bus rather than CAN.
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Re: Can bus monitor with avt

Post by antus »

AVT is not a J2534 device, it runs its own protocol. I guess you mean bus speed?

So without spending much time on it, looking in the AVT manual it says can4 speed is configured in hardware, and later in the guide

Code: Select all

7.12.9.1
Type2 Example Want to send three messages on CAN4 at 33.333 kbaud.
One message every 2.5 seconds. 
Using CAN4, Group2, Type2 operations, here is a sequence of commands to do this. 
It is assumed that this is from a reset condition. 
1.
; Enter CAN mode 
E1 99 2.
; Set CAN4 baud rate to 33.333 kbps
73 0A 04 0A 
3.
; Enable CAN4 normal operations
73 11 04 01 4.
; Enable CAN4 SWC transceiver for normal operations
72 12 03 
So I am going to assume that 33.333 baud is SWC (single wire can) and there is a sample script in the link above for that. And your AVT may or may not have been optioned with the hardware. Dont confuse the PC side speed (pick the fastest available for that) with the can bus speed (configure that in the dwn script)
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
Vampyre
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Re: Can bus monitor with avt

Post by Vampyre »

Thank you both antus I'll try that, ive got a vcx nano also so I'll try the drewtech tool also
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Re: Can bus monitor with avt

Post by Vampyre »

Built an arduino setup to monitor the swlan bus got some data. I can't find anything on line that actually helps decode it though. So much conflicting information its crazy.
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Gatecrasher
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Re: Can bus monitor with avt

Post by Gatecrasher »

Check this out.

https://github.com/commaai/opendbc/blob ... 818125.dbc

Whoever leaked that is a bonafide hero.
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