Open source GM OBD2 flash tool using a ELM327 device

They go by many names, P01, P59, VPW, '0411 etc. Also covering E38 and newer here.
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antus
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by antus »

Well, you dont need too, but it saves us a lot of time as we are developing the app. Being stable on the Vehicle for reads is the next goal we are working towards and its looking promising.
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
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by antus »

I just pushed up code to validate the additional block checksums on the large incoming packets, looks the same but seems to be working well and will be more reliable.
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by NSFW »

The good news: We just got a full read from my Corvette. It was mostly just a matter of improving the filtering and retrying logic to handle the part where we tell all of the modules in the car to be quiet and they all respond with "OK I'LL BE QUIET NOW." and "ME TOO" and "SO WILL I" while the app is trying to talk to the PCM. And it still took a couple of attempts to get it to work. But once it got past that step it worked well and produced valid .bin file.

The bad news: I think the AllPro hardware might need a little bit of work. For me it works reliably as long as I have a Y adapter in between it and the PCM. If I hook it up directly it can query the VIN and OS but it tends to miss incoming messages during the read process. That's a little weird, because you'd think that adding stuff between the PCM and the interface would make it all LESS reliable, not more reliable.
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by MudDuck514 »

Hi all;

NSFW, which AllPro are you using? The AllPro USB or the Dev Board like Pete? I find it interesting that his Android App seems to work while yours has a problem - unless he, too is using a Y cable since he seems to be using a BT adapter for his Phone, and a USB Adapter for his PC Monitor App.
I am wondering if there may be some unintended consequences of the design differences between the the two AllPro boards.

Once I can do so (money is tight right now) I want to buy the "Kit" version with the DB9 connector, so I can use the Cable I have from an ELM 327 that never worked. (PC sees the FTDI chip, but apparently the ELM interface is either DOA or NOT connected internally to the FTDI chip).

Mike.
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by NSFW »

I'm using the USB version of the AllPro. You might be tight about the bare-board version being better at tolerating noise. I wonder...
Please don't PM me with technical questions - start a thread instead, and send me a link to it. That way I can answer in public, and help other people who have the same question. Thanks!
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by 160plus »

MudDuck514 wrote:Hi all;

NSFW, which AllPro are you using? The AllPro USB or the Dev Board like Pete? I find it interesting that his Android App seems to work while yours has a problem - unless he, too is using a Y cable since he seems to be using a BT adapter for his Phone, and a USB Adapter for his PC Monitor App.
I am wondering if there may be some unintended consequences of the design differences between the the two AllPro boards.

Once I can do so (money is tight right now) I want to buy the "Kit" version with the DB9 connector, so I can use the Cable I have from an ELM 327 that never worked. (PC sees the FTDI chip, but apparently the ELM interface is either DOA or NOT connected internally to the FTDI chip).

Mike.
I have every version of the Allpro and have yet to notice any differences in the hardware(other then the BT one that doesn't work for this). Android has it's strengths in some area's like making things work with simplicity where Windows takes a bit more precision. At the same time it's much harder to deal with things that happen unexpectedly in Android.

For both tool's it just a matter of getting to the point you are able to send the flash kernel, once that's loaded it's smooth sailing. My app that is able to change a Vin or Serial number was already pretty close to the same point as sending the flash kernel so it was just a matter of adapting code I already had.
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by 160plus »

Had successful readouts in vehicle today with the Avt-852, Obdlink Sx and the Allpro. The Allpro still needs some tweaking but it's getting there.....just takes a couple of tries if there is a lot of chatter on the data bus, but once it's reading it's good to go. Was unable to test the J2534, I've never had it hooked up to my netbook and the drivers for it didn't want to play nice with windows 10...go figure.
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by antus »

We know what the allpro needs (the right timeouts for the multiple responses to the 4x request in car). Thats next on the list.
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
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by MudDuck514 »

Hi all,

Has any progress been made in the past couple of weeks?

Mike.
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Re: Open source GM OBD2 flash tool using a ELM327 device

Post by 160plus »

MudDuck514 wrote:Hi all,

Has any progress been made in the past couple of weeks?

Mike.
NSFW is going to verify the Obdlink Sx in car again to make sure the last of the issues have been resolved hopefully in the next couple of days.

Flash kernel is still being revised but is pretty close to being ready as well :thumbup:
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