Jump to content

Link user CAN help


Recommended Posts

Hi Guys,

Need a little help setting up the G4+ to receive some data from a Compushift Transmission controller.

Adam you helped me with this through facebook, but didn't seem to receive anything, so wanted to make sure I'd done it right or we have the right settings.

In the facebook post you gave me the following settings

20200923215948-ddd196a8-la.png

20200923215950-ac778d88.png

20200923215951-01babdc3-me.png

 

But using these settings I didnt get anything received on CAN DIG #8

Now I had a look at the HGM Compushift Wiki and they have the J1939 CAN spec in Excel format.
The CAN function I want is

IFSKF1K.png

 

Looking at the ID, translating the HEX to dec is 15729152. So is this the correct ID or 217055998? Also having trouble understanding/translating the Signal Byte and Bit.. See you have overlay-ed the numbers for it but how come it seems to go backwards? If somethin in J1939 was on Byte 2 Bit 2 Width 2 would that be Start 21?

Also the TCU has accelerometers (X,Y,Z) and also available on CAN. Is it possible for the Link to capture and log these?

HeWAqI8.png

 

 

Thanks greatly in advance for any advice.

 

 

Link to post
Share on other sites

I think the ID 217055998 is still correct as their document is missing some of the ID.  

But looking at that DBC file again I do see one possible issue, I think we should be looking at byte 0, not byte 1.  So leave everything else the same but try changing the start position for CAN DIG 8 to 3.

 

7 hours ago, wastegate said:

Also the TCU has accelerometers (X,Y,Z) and also available on CAN. Is it possible for the Link to capture and log these?

You could receive them as CAN analogs but they are not all that useful in G4+ as you cant apply filters and units etc to a CAN input.  

Link to post
Share on other sites
7 hours ago, wastegate said:

In regards to the filtering and units for the accelerometers, is that something the G4X can do?

Yes, the G4x is much more flexible with CAN inputs.  But most of the G4X ecu's have a 3 axis accelerometer on board anyhow.

Link to post
Share on other sites

Hey Adam,

I gave Byte 3 a go on both ID 217055998 and 15729152 but didn't get anything during a gearchange. I also tried Byte 11 for giggles on both IDs and nothing as well. I've attached by config and log just incase you would like to see it. But will reach out to Guy @ HGM and see if they can help too.

Cheers

 

Log 2020-10-4 12;12;09 pm.llg Scott's Map 07052019 - Flex Tune - Nick edit 04102020 - cold start better - new VVTI map WIP - Elite Gauge CAN - Cruise Changes - base fp 3bar - Accel Enrich - Idle Ign - IAT Fuel off.pclr

Link to post
Share on other sites

I just had a quick look at their wiki myself and the ID is different than the excel screenshot you attached earlier, It has the C on the front.  There is also a note that you may have to place a 3 where the x is, but that doesnt look right to me so try it without first.

Try the map attached.  Watch CAN Dig 7 & 8 as I have put one in byte 0 and one in byte 1.

RJJYMTr.png

 

Try this1.pclr

Link to post
Share on other sites

Try channel 6 ID as 3472891907, this is with the x replaced with a "3".  Otherwise you are going to have to contact them for a more firm answer or example of an output message. 

Link to post
Share on other sites
  • 2 weeks later...

Just to update, as things get confusing, managed to capture some data. Still working on getting the shifts transmitted but it's certainly in HGMs court now, likely need a input shaft speed to the controller as well to know when it's starting the shift.. They wrote a custom firmware to bypass this but still not getting anything on the shift.

I am getting the following though which just shows something is getting through.
Using Receive CAN ID 217055747 (CF00203) I got from Guy @ HGM
Start Pos 5, Width 2, LS, Unsigned = Torque Convertor Locking Up
Start Pos 7, Width 2, LS, Unsigned = Gear Engaged (Shifting from P to D etc)

From the data HGM supplied, looks like the Shift should be on Start Pos 3 in the Link. Not logging anything on that bit so will see what HGM come back with. They have been more than helpful to try and get it working.



 

HGM CAN1.png

HGM CAN2.png

Link to post
Share on other sites
  • 2 weeks later...

Update, HGM fixed the firmware and now have gear change request. 

Thanks Adam on the torque reduction strategy, works a treat. Just need to fine tune it. I've reduced the IGN trim retard a little as I don't have 20 degrees of timing in some spots and it's getting retarded too much and seems to spike boost. 
image.thumb.png.0d7ba91775fc64058d3182cb758b2133.png
 

Link to post
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.

Loading...
×
×
  • Create New...