Re: JTAG(ish) access to IPC V850
Posted: Wed Dec 21, 2022 2:45 am
very well done. good solution!
Electronic Fuel Injection - Developement & Tuning
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Gatecrasher wrote:Decided to make this a little less ghetto. I took some measurements and 3D printed a pogo pin jig that fits into the back of the cluster housing. I'm pretty sure this is how Visteon would have programmed these during manufacture. I was really lucky that the PCB contacts used exactly the same spacing as generic perfboard.
It was tedious as hell getting this thing assembled without breaking the pogo pins. I'm even worse at CAD than I am at writing code, and there's enough slop in my printer that everything was a really right fit. But somehow, miraculously, it actually works. I dumped another cluster without opening it. I've also got the serial console for the IMX chip hooked up and working. If I can get flash access to the IMX, this thing will be completely jailbroken.
Gatecrasher wrote:The V850 does CAN, power control, backlighting, and the analog gauges and indicators. The IMX handles the LCD, MOST, LIN bus, and HUD.
The Dx4 series has been close enough to the Fx4 series that I've been able to find all the registers I need. But obviously "close enough" won't cut it when you're trying to write something like a kernel.
CS+ ships with definition files for 77 different V850s. They're not in plain text, but they're close. It has register locations, along with a ton of other stuff I haven't figured out. I only just got it loaded up today, and I've barely glanced at this stuff. It was just dumb luck that I saw a reference to the file in the UI and decided to check it out.
Here's an example from DF3524.800. There's the register name in plain text FCN0GMCSPRE (FlexCAN0 global clock selection register) and then the register address a little later. FF480008.
These are installed at C:\Program Files (x86)\Renesas Electronics\CS+\CACX\Device\V850E2\Devicefile.
It might be worth figuring out how to parse those definition files and translate them into Ghidra scripts to label the registers.