Jeff's winter Corvette thread.

[Jeff V.]

On of the really cool things Chevy offers on the C7 is the Performance Data Recorder (PDR) from Cosworth. It's an integrated video and data acquisition system paired with a version of Cosworth's data analysis software that's scaled down from what they use on pro race cars. It takes data from an onboard camera, high speed GPS sensor, onboard accelerometer, and the car's CANbus. It saves all of this to a dedicated SD slot in the glovebox, complete with the graphic overlays and the performance data.

You can also use it as a dashcam and it has a valet mode.





Unfortunately, it wasn't available in 2014 at all. And from 2015 on, it was only bundled with the factory nav system.

Early on I had some ideas about trying to add it to my car, but I gave up due to the complexity and the high cost of the parts. Mainly the control module itself.

Then two things happened. First was a guy on the Corvette forum claimed to have a dead 2015 PDR that failed a software update. Second was some 6th gen Camaro guys successfully retrofitted PDRs to their cars. Now I don't have any need of this at all, but I figured it might be interesting to poke around with.

I got in touch with the guy who had the part and picked it up for $50, shipped. These things normally go for $500-900 in working order. Brand new they're $1400.



I hooked it up to my bench harness, and sure enough, I was able to pull some diagnostic data via the scan tool



I also managed to find a serial diagnostic port on the board. That's the first time I've ever found one of those on my own

Code: Select all

*LOAD**LOAD*Uncompressing Linux... done, booting the kernel.
Linux version 3.2.0+ (afarrell@CNT1BS1) (gcc version 4.7.2 20120731 (prerelease) (crosstool-NG hg+default-0dfc9c1fcb34) ) #1 Mon Feb 9 12:40:20 GMT 2015
CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=50c53c7d
CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
Machine: Marlin PDR
bootconsole [earlycon0] enabled
vram size = 4194304 at 0x0
reserved size = 4194304 at 0x0
FB: Reserving 4194304 bytes SDRAM for VRAM
Memory policy: ECC disabled, Data cache writeback
On node 0 totalpages: 74752
free_area_init_node: node 0, pgdat c0355498, node_mem_map c0375000
  Normal zone: 728 pages used for memmap
  Normal zone: 0 pages reserved
  Normal zone: 74024 pages, LIFO batch:15
omap2_set_globals_tap 81000081
omap2_check_revision 81000081
OMAP chip is TI8148 2.0

etc etc etc

I can see when it boots up that it crashes when it tries to pull some data off the main flash memory.

Code: Select all

VFS: Mounted root (romfs filesystem) readonly on device 31:4.
devtmpfs: error mounting -2
Freeing init memory: 140K
Kernel panic - not syncing: No init found.  Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
Function entered at [<c000f325>] from [<c021d2a9>]
Function entered at [<c021d2a9>] from [<c021d143>]
Function entered at [<c021d143>] from [<c02f45c7>]

It looks like this thing has two processors. One to handle communications with the car and scan tools, and one to run the actual PDR interface, video capture, and data acquisition tasks. It's this second CPU that's fragged.

I only had access to the 2016 firmware with my GM subscription, but Matt was generous enough to send me some 2015 firmware update files he got his hands on.

With all that in hand, I just might be able to resurrect this thing.

[DCIV]

Wow. That’s kick ass.


Coop

[mjannusch]

Hopefully you can reflash it and be back in business. I think the files just go on the root of a usb drive formatted as FAT, but if it doesn’t boot to the display then it might have to be flashed another way.

[Jeff V.]

The files just go on the root, like you said. GM's programming software formats a USB drive and downloads the files directly do it. The HMI and instrument cluster work the same way. Don't ever load a USB update for your HMI or cluster though. Unlike the PDR, you need to do a calibration step after the firmware is loaded. You need an SPS subscription and an MDI for that part.

I'm 99% sure this thing has standardized TI JTAG ports on it. It's not all hidden and obscured like so many other automotive parts. So I should be able to do a super low level reflash on it once I figure out how to extract the firmware image from the files. It's compressed with a different method than the HMI files. I haven't spent much time on it yet. I'll figure it out.

[ChargerX3]

Back door Jeff.

[tabasco122]

[quote=""ChargerX3""]Back door Jeff. [/quote]

thats what they called him in high school :d ontknow:

[Chris GTO TT]

[Jeff V.]

[Chris GTO TT]

Bumper already fell off? GM build quality!

[ChargerX3]

Don’t scratch that paint! Is this all for the front lip install?

[vr4]

[quote=""Chris GTO TT""]Bumper already fell off? GM build quality![/quote]

No that would be a VW problem

[DCIV]

Fuck. I would never get that back on correctly.


Coop

[Jeff V.]

I had to take it off to put my Z06 grille on. I'm also doing the splitter, and a few other things.

[Chris GTO TT]

[quote=""DCIV""]Fuck. I would never get that back on correctly.


Coop[/quote]

honestly modern bumpers are usually pretty easy to reinstall without changing the gaps. I had the bumper off our old Legacies countless times.

[Jeff V.]

There's two really annoying clips up where the bumper, fenders and hood all come together on each side. But once you know the trick to it, it's not bad. I only had to make one adjustment to get it back into alignment.

[mjannusch]

What’s the trick? Spyder should be off the lift soon so I can tafkle the same project on mine...

[Jeff V.]

Damn. I knew I should have taken pictures of that.

Basically you remove or release every fastener except those. Then you can lift the bumper upwards and open a gap between the bumper and the inner edge of the headlights. That gives you enough room to sneak a 1/4 drive 7mm socket in there. You can loosen the metal clips and release the bumper tabs much more easily.

That's where I had to make an adjustment on mine when I put it back together. I lined up those metal clips with the witness marks from the bolts. Then I just snapped the bumper back into place. The driver's side lined up nicely, but the passenger side needed some adjustment. So I loosened the bracket again and slid it over where it needed to go.

You don't really need a lift if you're only doing the grille. But it does make it a whole lot easier.

[mjannusch]

After some of the crazy shit I had to do on the Spyder to make little adjustments or fix things, I’m not worried at all about the Stingray. There’s no way it can be worse than trying to get a clamp tightened on the return line to the tank.

I agree that a lift isn’t needed to do the grille, but I promised my wife that only one car at a time can be taken apart.

[Jeff V.]

See if this helps. Put painters tape in the green areas. Once all the fasteners are removed, pull out at the edges by the wheels. Then lift the whole bumper straight up. That'll open a gap just big enough to slide the socket into the path marked in red.

[mjannusch]

OK, thanks for the tip, I'll try that!