PIC-based IE-Bus (AVC-LAN) interpreter

BUMP!

There certainly are a lot of open-ended posts on this, looks like there are a lot of people getting nowhere on the topic.

For those who have expressed an intrest in learning a bit about the AVC LAN, and potentially making your own goodies or hacking some existing goodies, I have been spending a few hours doing just that. As posted in many other areas of this forum, there seems to be minimal information on what is actually going on, presumably because Toyota wants it that way.

To that end, I have put together a snooper based on the above code and written some simple software to give a bit of a clue as to whats going on. I have spent considerable time scouring the different websites I stumbled across, and extracted as much info as I could in an effort to make heads or tails of the protocol.

I would be happy to make available pre-programmed PIC chips and a circuit which would allow snooping, prehaps if there is enough interest, I could put together a kit or pre-assembled unit if it isn't too price prohibitive.

Plans and software are still in the devemopement stage, but have a look at the attached picture to get an Idea of where this going.

My goal is to get enough understanding to allow myself (and others) to do things similar to what the commercial products (like the lockpic, and others) do, or at least understand how they work. This snooper should be compatible with most Toyota products, just some of the addressing changes by model, this can be filtered out in the software later in developement.

There is limited sample information on the internet, To continue with development, I need some more samples to analyze and help from anyone who wants to assist in "breaking the codes".

The package is in no way comprehensive, but if you take a bit of time, you can start to see how things start to come together.

Discussion on potential code meanings is welcome, I can post a short tutorial about what I have learned so far if anyone is interested.

Thanks to Marcin with his informative website (link in previous post), William Rouesnel who's project this is based on, and many others who have posted snippets of info that have gone into this.

Please let me know if there is interest in this or am I just re-iterating previous dropped projects.

Thanks,
Ken

 

Just a note on the 4 resistor setup: I tried it out with a 16F628A, got it to decode no problem, Nice easy circuit for a sniffer, I just could not get it to send back to the bus. On my scope it looks like there is not enough drive and the waveform is distorted, looks like there is a capacitive component involved somehow, got curves instead of square waves no matter which way I adjusted the circuit.

I'm going to see what else I can come up with. At this point it looks like the CAN-BUS chip might be needed for transmit.

I'll keep you posted. In the mean time at least the sniffer only is now very few parts.

Ken

 

Repeated below ...

 

I saw that site a while back, I didn't see more pins used, I did see two pins for the comparitor and two for the output part of the circuit but maybe I missed something, I'll look again.

I tried various combinations that were similar with no luck. After looking a bit closer at the ATMega8 datasheet, it indicates that the outputs are similar to FET drive whereas the PIC chips have what appears to be a standard TTL type output. At least it gives me something else to try, maybe if I setup a FET switching circuit on the out put it'll be enough to do it. I'm going to look at the CANBUS IC specs to see if that's what the outputs there are configured like.

Just got to find the time to do some more work on it ...