RaceChronoDiyBleDevice/can_db/ft86_gen2.md

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FT86 gen2 cars (2022 Subaru BRZ, Toyota GR86)

For details on how to connect to the CAN bus, as well as more information on the information available on the CAN bus, see https://github.com/timurrrr/ft86/blob/main/can_bus/gen2.md

Special thanks to Ken Houseal for his early legwork on finding some of these data mappings!

Here are CAN IDs and RaceChrono equations for data channels that should be enough for most people:

Channel name CAN ID Equation Notes
Accelerator position (%) 64 E / 2.55
Brake position (%) 313 min(F / 0.7, 100) The 0.7 divider seems to be a good value to get 100% at pressure slightly higher than those you're likely to use on the track for cars with no aero. You can use 0.8 or 0.9 if you see 100% too often.
Brake pressure 313 F * 128 Coefficient taken from 1st gen cars, seems to match fine?
Coolant temperature 837 E - 40
Engine RPM 64 bitsToUIntLe(raw, 16, 14)
Engine oil temperature 837 D - 40
Speed 313 bitsToUIntLe(raw, 16, 13) * 0.015694 You may want to check the multiplier against an external GPS device, especially if running larger/smaller diameter tires
Steering angle 312 bytesToIntLe(raw, 2, 2) * -0.1 Positive value = turning left. You can remove the - if you prefer it the other way around.

Advanced CAN IDs

Below is a table with a few more data channels that might be useful for more detailed analysis. When adding more channels, be aware that it will increase the file size of your RaceChrono sessions, and might negatively affect the update rate of the more essential channels, due to limited Bluetooth bandwidth. However, the communication protocol in RaceChrono is smart enough to optimize Bluetooth usage if multiple channels share the same CAN ID. As a general rule, if a new channel has the same CAN ID as an existing channel (such as "Yaw rate" using the same CAN ID 312 as "Steering angle"), then adding it should not affect the update rates. Adding a channel based on a new CAN ID (such as "Clutch position") will likely negatively affect the update rates of all other channels.

Channel name CAN ID Equation Notes
Clutch position (%) 577 (F & 0x80) / 1.28 100 is "clutch pedal depressed", 0 is "clutch pedal released"
Lateral acceleration 315 bytesToIntLe(raw, 6, 1) * 0.2
Longitudinal acceleration 315 bytesToIntLe(raw, 7, 1) * -0.1
Combined acceleration 315 sqrt(pow2(bytesToIntLe(raw, 6, 1) * 0.2) + pow2(bytesToIntLe(raw, 7, 1) * 0.1))
Yaw rate 312 bytesToIntLe(raw, 4, 2) * -0.2725 Calibrated against the gyroscope in RaceBox Mini. Gen1 used 0.286478897 instead.

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