Jump to content

Odo tick in User Defined CAN


007

Recommended Posts

Hi. I'm going to be building a FD2 Civic with a K24 engine and a Link G4+ Thunder. I plan to drive the gauge cluster using the User Defined CAN feature. I've managed to figure out everything except a tiny detail related to the digital odometer.

Honda sends an "odo tick" once every 10 meters to the cluster. This is a 1 byte value that counts up every tick and cycles back to 0 after 255 and repeats. Every 10 ticks, the cluster increments the odo by 0.1. I've searched all the available data items to send in a CAN frame and haven't found a speedo pulse count or anything I could use to enable this feature. I see only speedo out (status), but that won't do. See the attached graphical representation of the CAN data.

Am I missing something here? If not, could this feature be added in a future firmware update?

 

Thanks in advance.

speed.png

Edited by 007
adding graph
Link to comment
Share on other sites

That's weird that the odo signal comes from the engine ECU, you would normally expect it to come from the ABS module?

There is no way to do this at present, unfortunately that is the problem with OEM buses - all manufacturers dream up some different way of transmitting the data, many with arithmetic applied or bit stuffing etc so there are just too many possibilities to cover with a set of generic CAN functions. 

We would typically need to write a predefined stream to get this sort of function working, and that would be weighed against demand.

As luck would have it I believe we are working on a plugin solution for this platform in the near future so there may be some hope.  I will talk to the engineers next week and see if I can get any more info.

Link to comment
Share on other sites

Hey Adam. The ABS module provides individual wheel speeds in a 8 byte frame. However, the speed displayed on the gauge and the odo tick information comes from the ECU utilizing input from the vehicle speed sensor mounted on the gearbox.

I understand that it will take a lot of generic CAN functions to cover all possible OEM strategies, but in the meanwhile, would it not be possible to add a wheel revolution counter for either one or all four wheels, similar to the engine revolution counter that is already available? I feel that is a generic enough function for this purpose.

I would really appreciate it if you could add this in. It is the only fly in an otherwise perfect ointment.

Good to know that you are working on a plugin solution for this platform. I have reverse engineered a fair bit of the CAN structure to drive the gauge cluster, and would be happy to share that information if that will be of any help to you.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...