AVT 852 Commands and Trifecta Tuning

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morecircles
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Re: AVT 852 Commands and Trifecta Tuning

Post by morecircles »

antus wrote:How are you collecting that data? I dont think you are interpreting it correctly. I think you might have lost sync and be looking a mid parts of can messages, not AVT commands. 50 60 and 50 60 00 look like the same fragment, just with the break in different places. Just the same I dont think you can rely on the start being the start either. The AVT commands are in the manual, so if they dont line up then there is a problem with your process.
I have a software called "Device Monitoring Studio" running prior to starting the Trifecta datalogging software. It is a serial monitor that captures each frame sent through the COM 6, which is the FTDI usb-serial chip in the AVT-852.

I do believe that I am collecting my data correctly. Device Monitoring Studio time stamps each packet sent out. So far, most of the data collected looks robust, and I have interpreted them in accordance with the AVT manual as follows: http://pastebin.com/nneHfYZM (please pardon the mess, it looks much better in excel).

So aside from the previous commands I mentioned earlier, I will have to interpret the CAN bus commands as well. This seems particularly daunting as I do not believe a universal standard exists. Some direction in this regard would be appreciated.

Thank you again for the help.
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Tazzi
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Re: AVT 852 Commands and Trifecta Tuning

Post by Tazzi »

morecircles wrote: I have a software called "Device Monitoring Studio" running prior to starting the Trifecta datalogging software. It is a serial monitor that captures each frame sent through the COM 6, which is the FTDI usb-serial chip in the AVT-852.

I do believe that I am collecting my data correctly. Device Monitoring Studio time stamps each packet sent out. So far, most of the data collected looks robust, and I have interpreted them in accordance with the AVT manual as follows: http://pastebin.com/nneHfYZM (please pardon the mess, it looks much better in excel).

So aside from the previous commands I mentioned earlier, I will have to interpret the CAN bus commands as well. This seems particularly daunting as I do not believe a universal standard exists. Some direction in this regard would be appreciated.

Thank you again for the help.
Its not this mob is it?
trif.PNG
trif.PNG (44.9 KiB) Viewed 6914 times
Deceiving little app. Gets alot larger after it decompresses at runtime.

So first up, if you want to learn/understand what they are sending. You will need to start leaning some programming your self. Make an app that will read the AVT commands properly and actually display them on screen in a legible manner rather than have a mash of serial bytes from the serial monitor. You will need to figure out how to connect two ports at one though ;)

Or, next, simply grab an OBD2 device like an ELM, set it up for CAN 11bit 500kb/s and then log away!
Alternatively, if you want to actually use an AVT, you will need to start learning the AVT protocol and might as well make a simple program to monitor the bus chatter and just watch what is sent by the software :thumbup:
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RoninDusette
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Re: AVT 852 Commands and Trifecta Tuning

Post by RoninDusette »

I know this is an old thread, but I too have a Trifecta tune (elite) for my 2015 cruze (1.4t, e78). Here is a candump log of the entire process start to finish. You can see where it requests mode 27 access, and it's granted, and when you arbitration ID stays the same for thousands of lines is where the file is being transferred. Just throwing this up here for reference, and maybe someone can help me decipher some of it? I am really just looking to understand how it works. I put their app and calibration file through hexdump and binwalk, and was able to see that they use at least in part, code from Palmer Performance. This is likely how they are able to flash their tune and turn it off and on; pretty sure some of it is going to the BCM (dashlogic is palmer's product, which communicates with the BCM. Also they brag about their transparency feature and that a dealer cannot tell it was tuned, nor does it increment the read/write count of the PCM... I am almost sure that it's because they are putting the calibration elsewhere, and that the dealer wouldn't check the BCM. Couple with the fact that they are running some of palmer's code for dashlogic, I'd say this is a fair assumption.). Your thoughts, please? :)

It's huge, so it's zipped.

https://drive.google.com/file/d/1VK4T7V ... sp=sharing
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antus
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Re: AVT 852 Commands and Trifecta Tuning

Post by antus »

I think those companies and others have licensed tunercat software variations, so the similarities can be expected.
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