Software On ELM Street - OBD2 Software Development

[Tazzi]

Yeah, the AVT cables are like $300+ which for the time being isnt quite what Im after.. would be really useful for this reverse engineer stuff.. but the elms are doing ok so far so why stop with them now haha.

An android app to dump the pcm.. sounds like a great project durahax!. Well I was originally posting bits and pieces of coding and the project at the beginning, but due to a lack of changes or downloads, I just continued pumping out the compiled application for testing.

At first, the application was more heading to being able to communciate only by VPW, But push came to shove and we are now doing VPW, Can 11bit (high and low) and Can 29bit (high and low). And due to the amount of cuts and changes I do to repair any bugs, the coding hasnt been nicely layed out or commented to keep up with what everything does. Still need to go though it all, cleanup any unneeded coding and add a shitload of fault catches.

[Tazzi]

*Sigh*.. Well, possibly done the silliest mistake of all.. after coding in 5 cables worth of info and delegating all tasks between them... I realized that I only have 3 usb ports

Its one of those days you feel like this ->

Also looks like the tech2 VCI module has almost completely crapped it self. Looks like Im up for another module now. Guess I could try pull it apart and attempt to fit a new serial connector onto it since that part is causing the hassles!.

[Tazzi]

Shes alive!.. after reflowing the solder on the serial port pins.. seems to be a happy camper now.

Iv reverted to 2 ELM cables connected for simplicity sake. All seems to be working well going into the tech2's main engine menu screen. Did it very quickly!

Code: Select all

[12:40:20:412]   Tech2 Sent: 6C 10 F1 20 64
[12:40:20:445]   Received: 6C F1 10 60 72 
[12:40:20:663]   Tech2 Sent: E9 3A F1 3C EC
[12:40:20:696]   Received: C8 3B 10 80 5E 
[12:40:20:846]   Tech2 Sent: 6C 10 F1 3C 08 F0
[12:40:20:883]   Received: 6C F1 10 7C 08 00 BA 49 7F E1 
[12:40:20:921]   Tech2 Sent: 6C 10 F1 3C 93 D4
[12:40:20:967]   Received: 6C F1 10 7C 93 41 44 D8 
[12:40:20:999]   Tech2 Sent: 6C 10 F1 3C 0A CA
[12:40:21:046]   Received: 6C F1 10 7C 0A 00 C0 28 CE D0 
[12:40:21:079]   Tech2 Sent: 6C 10 F1 3C 0B D7
[12:40:21:126]   Received: 6C F1 10 7C 0B 00 8E CD 55 C0 
[12:40:21:165]   Tech2 Sent: 6C 10 F1 3C 0D 99
[12:40:21:214]   Received: 6C F1 10 7C 0D 00 8E CB F4 A8 

Will give a go on the DPID section and see what happens *fingers crossed*

[Tazzi]

Well Im stumped. Its not a matter of keeping up now. But Undertsanding what the hell the tech2 wants!
I am mimicing exactly what VX had posted up.. but seems the tech2 isnt happy.

I starting firing off the DPID responses.. and while logging, the tech2 gets to here... waits then beeps at me as if its looking for something but not getting it!

Code: Select all

[13:50:34:001]   Tech2 Sent: 6C 10 F1 22 11 72 01 B9 
[13:50:34:061]   Received: 6C F1 10 62 11 72 00 01 BF   <- I sent to tech2
[13:50:35:173]   No Chatter Detected..1    

I send back a response to that request, and continue sending off the DPID responses. Tech2 pauses for about 1sec, then beeps at me and repeats the whole DPID setup ect. Hmmm.. it seems Iv hit that point that I definitely need a pcm to listen in on whats happening with the tech2. Ebayers seem to only want to sell them from $300+.

My next possibility is now to apply a 3rd ELM cable. Where as soon as the "spam requests" comes from the tech2, I can set the 3rd cable to do its thing. And Cable 1 can continue monitoring and cable 2 can do any other "general" responses.

If that doesnt work... then Im officially stumped!

[VX L67 Getrag]

I know how you feel it feels I've been going backwards with what I've been doing to!

If there's anything I can test out for you let me know!

[Tazzi]

Ah pitty, dont worry.. Im sure everything will just makes sense and click one day and you sort it out!

Anyways.. little bit of progress.. the screen is showing me some data!!... So maybe its down to invalid frames Im sending back? Maybe it wants proper VY V8 info back or something?

*Edit

WoooHoooooooooo
Got it working!
Instead of only beeping at me with no data showing.. it now beeps at me with data showing!
Which the three elms and tech2 all on the poer supply, I had to bump up the voltage as I started getting weird frames due to low power!

Heres the current "master piece" setup... excuse the mass of wires.

[VX L67 Getrag]

LMAO nice mess, good work!

[Tazzi]

I noticed today.. that I can read any info from the tech2 when only attaching pin 2 (VPW pin) to the tech2's corresponding pin. Didnt need ground or 12v power supply.
But.. to write back to the tech2.. I needed ground and power, must need more juice to send then when reading.

Or it could just be I have special elms!

[antus]

nice work

[irad]

I am brand new to this site. I noticed there was discussion about the scantool.net software not working with generic elm327 devices. The scantool.net software was modified after version 1.14 to prevent generic elm327 usb devices. I downloaded scantool.net version 1.21 source and modified it to work on my generic elm327 1.5 device. My changes are in the reset.c file which I am uploading.