G4+ Integration to OEM CANBUS systems

Hi team,

Whilst not technically new to PCLink in general I am struggling to get my head around the CAN setup section.

Is there a tutorial on converting the hexadecimal figures that a CANsniffer the likes of arduino outputs into the multiplier/divider system that the Link uses?

The Link help file has very limited information on this topic and I cannot find much information in my research.

I say this as im just about to begin wiring a G4+ Thunder into my RX8 and would like the Link ECU to replace the OEM unit to retain control of all of the functions of the dash and ABS/DSC systems ETC.

Adam, when he was at Link was kind enough to add some functions to a map to get most basic functions working on the dash, however I would like to expand on this for more functionality eg: odometer, cruise control light etc.

does the G4+ software tutorial cover CANBUS in any of the modules? I have no problem buying the course and intend to, once the wiring side has been completed.

There is a thread in the Link forum with some background info regarding this project.

https://forums.linkecu.com/topic/7433-g4-mazda-rx8-can-bus/

Thanks.

I saw your post on the Link forum but you didn't actually ask any question there. If you want help it would be best to ask your question there to keep it in context. The G4+ software course doesn't cover any CAN bus reverse engineering. You can use windows calculator to convert between Hex and decimal. Use the test calculator in PC Link to see how the multi/div/offset effects the raw value.

The RX8 CAN map I attached to that post should make most of the car work. From memory the only thing that doesn't work is the odometer. The G4+ ecu does not have a distance channel so the is no way to generate the odometer tick. Cruise control light should be no drama, originally when I done that map it wasn't possible but we have since added cruise control light functionality to the G4+ firmware.

Thanks Adam.

My question here was more to do with the G4 course with regard to CAN setup.

Mostly just trying to find a worked example of setting up as its all a bit intimidating to start with.

The thread on the link forum is a wealth of info so will be keeping that there.

I see that there is a CAN course available now. Do you think that'll be worth taking part in?

Thanks again.

As I mentioned above the G4 software tutorial doesn't cover any CAN stuff. The new CAN course does cover CAN fundamentals and some basic reverse engineering examples which you will probably learn something from. The only Link specific example that I remember from that course was setting up transmit to a motorsport dash so that probably wont help you much, but it seems more like it is the fundamentals you need help with anyway?

Your intent is still not clear to me, what are you wanting to do besides what is already done in the RX8 file on the Link forum?

Thanks again Adam.

I basically just want to know as much as possible about how my car works.

I've watched so many videos on CAN however everything is Hex and I've never found one that shows the calculations that Link uses to setup.

I'd love to get the cruise light working too.

I'm grateful for the work you have put in and taking time for replies here.

Hex and decimal notation and conversion between them is just something you have to get used too. Many CAN tools allow you to display either. If not either windows calculator, one of the many online tools or a hex/dex calculator app on your smartphone. Decimal is often easier for a human to read and interpret quickly as that's what we are used to working in everyday life, but when you start doing multiple byte values and other implementation factors such as endianness come into it then it is often easier to work in Hex.

Decimal is base 10, so your numbers are 0,1,2,3,4,5,6,7,8,9.

Hex is base 16 so your numbers are 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F.

But Im pretty sure that is covered fairly well in Zac's CAN course.

For the cruise light, do you know what ID it is on and what the data needs to look like to control it?

Hi Adam,

I don't have cruise from factory and neither do of any of my friends to check.

the attached image is the only info I have with regards to the cruise light taken from Dave Black's spreadsheet).

He doesn't have cruise either so i assume his info is limited too.

Thanks again.

Did that spreadsheet you got this info from mention if that was the HS or medium speed bus? Im pretty sure I found the log I had from the RX8 and it doesn't have any ID's like 650 on the HS bus.

Anyhow, if you are sure that data is from the engine ecu HS bus, then the set up below would give you: Green light for cruise enabled. Yellow for cruise active, both lamps when cruise is locked out.

Can you please clarify, will this only work with a G4+ and not a G4?

Also where can I get CAN bus info from on a G4x, I’m looking to buy a new ecu but want CAN to be configurable to 3rd party devices so looking for information. The Link website seems very sparse in information regarding this!

G4 hasnt been produced since 2013, it didn't have user configurable CAN, just some fixed streams for displays etc. Back then the G4 was our lower cost ecu brand with some software and hardware removed, configurable CAN was one of the extra features you got in our higher cost Vipec ECU's - although much less capable than today's ecus.

To see what you can do with G4X it would be best to download the software and play around in one of the base maps. The help file has a lot of info as well as the "test calculator" can be used to see how data is enumerated and interpreted etc.