I’m going to be switching my project from using WiFi and RealDash CAN data format to wired using a supported usb to CAN adapter.
I’m doing this because the sensor hardware I’m using (esphome project) has recently added support for can bus.
They use the standard 11-bit or 29 bit CAN address format - https://en.m.wikipedia.org/wiki/CAN_bus
This may be sort of a noob question, but I’m trying to reconcile how realDash copes with the CAN standard addressing scheme versus what seems to be a different address bit length in RealDash can format (and associated required “header” I’m sending now). I perused the XML files for other ECU’s on GitHub and it seems straightforward. Does RealDash just expect the addressing scheme to be different when connected via USB?
Different CAN addressing schemes are handled by the adapters, so they are transparent to RealDash. The logic that handles the incoming data is exactly the same regardless if data comes from USB, Bluetooth or TCP.
What about the 0x44,33,22,11 sequence that I currently manually send now in my code that a standard CAN device is not going to send?
If you are using RealDash CAN protocol for custom comms, then always send the packages per docs:
Note that you cannot use the CAN adapters with RealDash CAN protocol as every adapter has their own serial protocol to communicate with.
I want to use a standard can protocol like will be sent by these devices:
Currently, I’m using these sensors to talk to MQTT and wrote some middleware in node-red to convert that to realdash can. I’m looking to eliminate the need for the middleware AND wifi in one fell swoop here, greatly enhancing the reliability of my system.
They can do analog to digital conversion of various sensors ,etc. I can define the address and frame and data that will be sent using their config file. I’m thinking I’ll define the corresponding frame and target in the XML file for realdash.
Can you take a peek at this and tell me if this seems like a viable direction? My main concern is if the data being sent by esphome will be understood by realdash.
Sounds like a good plan. Use one of the supported CAN adapters to read data from your CAN device:
Then write a XML that describes the CAN frames to RealDash. The CAN XML format is the same for all CAN connections and RealDash CAN protocol.
Excellent, thank you. I’ll get to work on it and let you all know how it works out.