MPH through CAN from tesla SDU to speedhut dials

[Kitlacey]

Hi all,

I'm wanting to send CAN messages, using the web interface, to some speedhut gauges to show MPH. I've been told I can use the 'speed' section of can messages but I don't know where to start.

Why tyres are 185 65R15s (it's a vw camper).

Please give answers for the 4 boxers on the web interface.

Thanks

[Bigpie]

Do you know the Can ID the gauges expect to see the speed message on and the format of the message?

[tom91]

https://openinverter.org/wiki/CAN_communication

Towards the bottom section "Mapping Values through the web interface"

This again is open inverter so there is no variable road speed gain at the moment. So you need to bake this into how you setup the RPM / Speed (motor) to convert it to a vehicle speed value.

Did Zero-EV/Fellten stop selling Tesla Drive units?

[johu]

Yes, say the display expects road speed in mph as an integer and the speed to mph ratio were 100 (1000 rpm equals 10 mph) then you'd enter 0.01 as the gain factor. Since 5.27.R the gain can be more or less float so that is now possible.
don't be surprised that after setting it up the gain will show as 0. That's because the print routine is still limited to 5 binary digits (and thus roughly 1.5 decimal digits)

[Kitlacey]

Do you know the Can ID the gauges expect to see the speed message on and the format of the message?

Not sure,

I used to have

CAN ID 599
Position 0
Bits 16
Gain 10

This was under a parameter titled 'roadspeed'

[johu]

And what was "roadspeedgain" ?

[Kitlacey]

And what was "roadspeedgain" ?

Sorry, I didn't have a setting for roadspeedgain

[tom91]

Upload your .JSON for the Zero-EV firmware it is in there for sure.

Line 10 "roadspeedgain"

[jsimonkeller]

Hi guys. I read this post because I have updated my firmware and roadspeed is no longer available and it was really helpful to understand the conversion, but I still have some questions:

I have the same speedhut speedo with the following CAN:

CAN ID 599
Position 0
Bits 16
Gain 10

My roadspeedgain setting was 8.06

Based on this, for speed do I continue to use the:

CAN ID 294
Position 16
Bits 16
Gain 1

and adjust the gain from 1 to 8.06 OR

CAN ID 599
Position 0
Bits 16
Gain 10

and adjust the gain from 10 to ????

I assume my speedo needs the 599 in the SPEED column with the updated gain, but wanted to make sure.

Thanks

[johu]

and adjust the gain from 10 to ????

We now sorted this in a live session. Jordan please correct if I give the wrong numbers.

Code: Select all

can tx speed 599 0 16 0.0818

We used custom command because speed was also mapped somewhere else and the old interface doesn't allow a second mapping of the same item. The new web ui allows that.

[jsimonkeller]

The above information from Johan is correct. My roadspeedgain reading had been 8.18 and this was the correct conversion. I hooked up my GPS speedo and took the 911 out for a spin and compared the readings on the GPS speedo to the CAN Speedo using this code and they were both tracking the same speed, so success!!! Thanks!!!!