Help needed - BMS canbus log data capture in Leeds for I-Pace

[Jacobsmess]

Hi all,
I'm potentially purchasing an I-Pace pack and hoping to provide some information to Tom91 (of SimpBMS) to help reverse engineer the pack for implementation on the simpBMS, as well as enabling my own use of 32 of the modules (from a 36 module pack).

However, this is something I have zero experience in so I was hoping someone might be able to aid in capturing some Can logs for Tom to work his wizardry on. Is anyone local to Leeds that could spare some time for the greater good?

Or explain to me like I'm 5 how I can achieve this myself.

Pack won't be in a running car unfortunately

[royhen99]

https://openinverter.org/wiki/Getting_s ... th_CAN_bus

[Jacobsmess]

https://openinverter.org/wiki/Getting_s ... th_CAN_bus

Thanks although I'd say that's written for someone more competent than a 5 year old....

[janosch]

Mandatory first steps:
- make sure you have 60 Ohm resistance across the bus
- understand CAN bus speeds
- understand a single CAN device doesn't do anything, you always need two at least
- power up with 12V


Then one or all of the following:
- play around with savvyCAN
- get a CAN crocodile, figure out how it works and hook it up
- connect a RaspberryPi with PiCAN adapter

Pack won't be in a running car unfortunately

this could be a problem as you might need to send it messages to get certain messages back out

Read as much as you can from that wiki page and the videos, see also https://en.wikipedia.org/wiki/CAN_bus

A nice pre-exercise might be to setup two devices on your desk and make them talk to each other and observe the traffic. Once you can do that you have acquired all the skills to read from any CAN device.

And lastly, once you have done all this and the knowledge is all new and fresh in your head, see if the openinverter wiki page could do with more/less information, making something clearer or a howto guide.

Good luck, CAN isn't too hard, you got this.


Edit, haha, I asked ChatGPT and it has some good ideas as well:

Debugging CAN communication can be challenging, but there are several steps you can take to help identify the problem. Here are some suggestions:

Check the physical connections: Make sure all the connectors and cables are properly connected and there are no loose connections. If the connections are good, check if the cables and connectors are damaged or have any signs of wear and tear.

Check the power supply: Ensure that the power supply to the CAN nodes is stable and consistent. Irregular power supply can cause the communication to fail or be unstable.

Check the termination: Make sure that the CAN bus is properly terminated at both ends. Incorrect termination can lead to signal reflections that can cause communication issues.

Check the baud rate: Ensure that the baud rate of all the nodes on the CAN bus is the same. A mismatch in baud rates can cause communication to fail.

Use a CAN bus analyzer: A CAN bus analyzer can help you to monitor the traffic on the bus and identify any errors or issues. It can also help you to isolate the node that is causing the problem.

Use diagnostic tools: Many CAN controllers have built-in diagnostic tools that can help you to diagnose and debug communication issues. Check the documentation for your CAN controller to see if it has any diagnostic tools.

Check for error frames: Error frames indicate that there is a problem with the communication. Use a CAN bus analyzer to monitor the traffic and look for error frames.

Check the software: If you are using custom software for the CAN communication, ensure that it is properly configured and there are no bugs. You can also try using a different software or library to see if the problem persists.

Consult the documentation: Check the documentation for the devices on the CAN bus to see if there are any known issues or limitations that could be causing the problem.

By following these steps, you should be able to identify the cause of the problem and debug the CAN communication.