[Ovmsdev] SPEEDO feature

Mark Webb-Johnson mark at webb-johnson.net
Sat Feb 25 09:10:28 HKT 2012

> What is the status of the digital speedo feature?

A developer asked about this off-list, and I thought it might be relevant to the wider community, so here it is.

The speedo feature is enabled by defining OVMS_SPEEDO_EXPERIMENT at build time (either in ovms.def, or via configuration parameter). It is currently enabled for the experimental configuration, and off for the other two.

The feature must also be enabled, after the module is powered up in the car, by setting feature #0 to a value >0. The value 5 is recommended as a good starting point. This feature #0 is volatile, and will be set to 0 if the module is powered down or rebooted.

The reason the feature is classified experimental is because while it seems to work, we are really not sure what affect it has on the car. Something unexpected might damage the car. Use it at your own risk.

Our warning is "The feature can transmit a lot of messages on the bus and is spoofing the car message. We can't see any affect (and we've even put an analyser on at the same time to see if any errors come up - they don't), but it is very intrusive to the car. One concern we have is if the car is using that message for anything else (but we can't see how it would as it also contains data for the battery level display, estimated miles, etc - it seems very very specific to that dashboard display). We really don't want anyone breaking their cars with this."

If you do use, please let us have feedback on the ovmsdev mailing list. We really need to know more about this and any impact on cars (good, bad or zero).

Regards, Mark.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openvehicles.com/pipermail/ovmsdev/attachments/20120225/8b7d25f6/attachment.htm>

More information about the OvmsDev mailing list