cars with DSC module, so all cars from 2007 onwards.
Byte | Meaning
---- | -------
0 & 1 | together with byte 1 represent the pressure of the braking system
2 | brake siwtch ON/OFF, information contained in bit 0 (MSB, from left)
3 | Not changing
4 | Not changing
5 | Not changing
6 | Not changing
7 | Not changing
Channel name | Equation | Notes
------------ | -------- | -----
Brake pressure | `(3.4518689053*bytesToInt(raw, 0, 2)-327.27)/1000.00` | multipliers are obtained from data from Leisurehound user on miata.net, may be wrong. Unit is kPa
Brake percentage | `min(0.2*(bytesToInt(raw, 0, 2)-102),100)` | this is an alternative to get brake percentage. When not pressed the value is 102, after braking and releasing it goes briefly down to 99 so you may see slightly negative percentage.
Throttle Position | `bytestouint(raw,7,1)*100/255.00` | Scale may need adjustment, doesn't take into account the offset for idle. Same value available in CAN ID 0x215 byte 6
Speed | `((bytestoint(raw,4,2)/100.00)-100)/3.6` | Raw speed data is given in km/h with a 100 km/h offset. The "3.6" at the end of the equation is needed to switch to m/s that is the unit used internally for calculation by RaceChrono. In the calculation RaceChrono will then multiply automatically for the correct value to transform the m/s to your choice of units (i.e. km/h or mph).
Accelerator Position | `bytestoint(raw,6,1)*2.00` | This is a percentage, increments of 0.5%
Throttle Position | `bytestouint(raw,6,1)*100/255.00` | Scale may need adjustment, doesn't take into account the offset for idle. Same value available in CAN ID 0x200 byte 7
spark angle, calculated load, throttle valve position
only interesting bit is the clutch switch
Byte | Meaning
---- | -------
0 | Calculated Load (%)
1 | Engine Coolant Temperature (°C)
2 | WIP: seems related to ignition timing (deg)
3 | Throttle Valve Position (%)
4 | Intake Air Temperature (°C)
5 | Always 00
6 | Always 00
7 | Always 00 (faults?)
Channel name | Equation | Notes
------------ | -------- | -----
Percentage | `100*(bytestouint(raw,0,1)/255.00` | can't find Engine Load on RaceChrono list of channels
Coolant temperature | `bytestouint(raw,1,1)-40` | RaceChrono does calculation in °C then converts to your unit of choice. Same data availble in byte 0 of ID 420
Throttle position | `100*bytestouint(raw,1,1)/255` | Scale may need adjustment. This ID should refer to absolute opening value, i.e. taking into account the opening at idle. Still, the value at idle for my measurements seems too high (11%...)
Ignition advance
Intake temperature | `bytestouint(raw,4,1)-40` | RaceChrono does calculation in °C then converts to your unit of choice
`0x4b0` is dedicated only to wheel speed representation
Byte | Meaning
---- | -------
0 & 1 | Front Left Wheel Speed
2 & 3 | Front Right Wheel Speed
4 & 5 | Rear Left Wheel Speed
6 & 7 | Rear Right Wheel Speed
Channel name | Equation | Notes
------------ | -------- | -----
Vehicle Speed Front Left | `((bytestoint(raw,0,2)/100.00)-100)/3.6` | Raw speed data is given in km/h with a 100 km/h offset. The "3.6" at the end of the equation is needed to switch to m/s that is the unit used internally for calculation by RaceChrono. In the calculation RaceChrono will then multiply automatically for the correct value to transform the m/s to your choice of units (i.e. km/h or mph).
Vehicle Speed Front Right | `((bytestoint(raw,2,2)/100.00)-100)/3.6` |
Vehicle Speed Rear Left | `((bytestoint(raw,4,2)/100.00)-100)/3.6` |
Vehicle Speed Rear Right | `((bytestoint(raw,6,2)/100.00)-100)/3.6` |