[Ovmsdev] OVMS V2.5 production / Renault Zoe support
mark at webb-johnson.net
Tue May 9 07:55:46 HKT 2017
On many modern cars there are multiple CAN buses used for different things. The approach is to separate different parts of the car onto different buses.
For example, the Tesla Roadster has three CAN buses, the Nissan Leaf has two, and the Tesla Model S and X have at least four.
It is helpful for OVMS to be able to connect to multiple CAN buses to be able to have more functionality (control parts of the car not directly connected to a single CAN bus).
> On 9 May 2017, at 6:41 AM, Greg D. <gregd2350 at gmail.com> wrote:
> Hi Mark,
> I'm curious why there would be an issue with using one of the three CAN
> bus ports for a down-stream device? Do some cars require connecting to
> all of them for normal operation? What else would they be used for?
> Mark Webb-Johnson wrote:
>> I’ve seen quite a few of these OBDII-plugin devices in recent years. Not just HUDs, but insurance company driving behaviour monitors, dongles, etc. While most modern cars provide at least some standard OBDII PID support (such as speed, fuel level, etc), Tesla have been notable in their absence of any such support.
>> Navdy, Exploride, Hudly, Garmin HUD, iScout; none work with Tesla cars.
>> Software wise it is quite simple to do. The only issue I see is dedicating one CAN bus port to this (but we’ve got three). On some cars, it might be possible to multiplex this on top of an existing CAN bus (so long as there is no conflict on the CAN IDs used or bus speed).
>> Regards, Mark.
>>> On 2 May 2017, at 7:37 AM, Greg D. <gregd2350 at gmail.com> wrote:
>>> Hi Mark,
>>> I'm really interested in the down-stream OBDII connection (ECU
>>> emulator). I would like to use it to drive a Wi-Fi Hotspot dongle
>>> (T-Mobile's "SyncUp Drive"). Thanks for including this.
>>> Besides providing a hotspot for the car's passengers, and the intended
>>> vehicle telematics, it could also give the OVMS module a Wi-Fi
>>> alternative to the 3G modem, at least when the car is awake. I presume
>>> the modem would be the preferred connection for lower power states.
>>> Mark Webb-Johnson wrote:
>>>> Along with some HUDs, I’ve been experimenting with a little OBDII
>>>> display that costs around US$25 (quantity: 1). Connection is via OBDII
>>>> (CAN bus) - the idea being that we will emulate an OBDII ECU on one of
>>>> our CAN buses that connects to this. So, we can output battery
>>>> temperate where the unit expects coolant temperature, SOC% as fuel
>>>> level, etc. MCU in that unit is a GD32F103 (like an STM32, but
>>>> 108MHz). Input is via a little jog-left, jog-right, push-to-click
>>>> button on the front. Just an idea and something I’m messing around with.
>>> OvmsDev mailing list
>>> OvmsDev at lists.teslaclub.hk
>> OvmsDev mailing list
>> OvmsDev at lists.teslaclub.hk
> OvmsDev mailing list
> OvmsDev at lists.teslaclub.hk
More information about the OvmsDev