Hi RealDash Team,
I am using an ESP32 as a CAN-to-USB bridge to display data from a Renault vehicle in RealDash using the RealDash CAN protocol.
The vehicle provides an 8-bit rolling counter (0-255) for fuel consumption. Each increment represents exactly 80mm³ of fuel. Because it is only 8 bits, the value rolls over from 255 back to 0 very frequently (every 20.48 ml of fuel consumed).
My questions regarding the best implementation are:
- If I map this 8-bit value to TargetID 258 (Fuel Consumed), does RealDash internally detect the rollover (255 → 0) and continue to accumulate the total volume? Or will the “Total Fuel Consumed” value reset or glitch when the byte wraps around?
- Given that I have a fixed increment of 80mm³ per pulse, would you recommend:
- A) Sending the raw 8-bit counter and letting RealDash handle it (if rollover detection exists).
- B) Linearizing the value in the ESP32 (sending a continuous 32-bit float/int representing total Liters) and mapping that to ID 258.
- C) Using TargetID 490 (Fuel Flow)? (Though my data is a volume counter, not a flow rate).
- For long-term stats (average consumption, trip fuel), does RealDash persistence for ID 258 work better if the “Total Consumed” value is an ever-increasing number provided by the hardware?
Setup Details:
- Connection: USB (Serial) @ 921600bps.
- Protocol: RealDash CAN.
Thank you for your time and for such a great tool!