20 KiB
Lua Scripting
Introduction
rusEFI strives to offer users as much flexibility as possible, to provide a completely user-defined control strategy for both primary and auxiliary actuators.
Basics
rusEFI provides a number of hooks to interface with the firmware and to manipulate its state and read/write the current configuration.
- Hooks for CAN bus communications; see CAN bus.
- Inputs from sensors can be read directly; see Input. You can also produce sensor values with Lua see https://github.com/rusefi/rusefi/wiki/Lua-Scripting#set-sensor-value
- ECU general purpose outputs see Output.
- Aspects of the engine can be controlled directly; see Engine Control.
- ECU Configurations can be accessed (read/write) via the
getCalibration()
hook, and manipulated via thesetCalibration()
hook.- Configuration names are dynamically updated to match the current firmware; see here for the current list: https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/generated/value_lookup_generated.md.
- ECU internal state, i.e. logic outputs from the firmware can be read via the universal
getOutput()
hook, and some can be altered via correspondingly named hooks i.e.setOutputName()
whereOutputName
is name of the output, e.g.setClutchUpState()
. See also: Output.- Output names are dynamically updated to match the current firmware; see here for the current list: https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/generated/output_lookup_generated.cpp.
- Hooks to read values from SENT sensors; see SENT protocol.
- A set of useful routines is provided; see Utility.
Some example uses are provided in Examples.
Conventions
- The Lua interpreter will trigger an error if there is a mistake in the program, check the rusEFI console to see errors and script output.
- Unless otherwise mentioned, all
index
parameters start with the first element at index at 0.
Writing Your Script
The entire Lua script is read at startup, then a script function called onTick
is called periodically by rusEFI.
Here is a simple script you can run to illustrate this behavior:
print('Hello Lua startup!')
function onTick()
print('Hello onTick()')
end
Controlling the Tick Rate
The function setTickRate(hz)
can be used to configure how often rusEFI calls the onTick
function. If your script does a lot of work in the onTick()
function it may run slower than the desired rate. Since the Lua virtual machine runs at low priority compared to other functions of the ECU, it is impossible to swamp the ECU with too much Lua work, so set the tick rate to whatever is necessary. onCanRx
runs at the same rate as onTick
n = 0
setTickRate(5) --set tick rate to 5hz
function onTick()
print('Hello Lua: ' ..n)
n = n + 1
end
Editing Scripts
To ease editing a LUA script an editor that supports Language Server Protocol (LSP) is highly recommended. For an option see LuaLS/lua-language-server
Hooks/Function Reference
User Settings
getOutput(name)
For example getOutput("clutchUpState")
getOutput("brakePedalState")
See https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/generated/output_lookup_generated.cpp for output names.
setClutchUpState(value)
setBrakePedalState(value)
Use setBrakePedalState to tell rusEFI about CAN-based brake pedal.
setAcRequestState(value)
Use setAcRequestState to tell rusEFI about CAN-based A/C request.
setEtbDisabled(value)
setIgnDisabled(value)
'setIgnDisabled' function for all kinds of cranking safety systems
setAcDisabled(value)
Disable/suppress A/C functionality regardless of what and how enables it, an override kind of deal.
getTimeSinceAcToggleMs()
getCalibration(name)
Gets current calibration value for specified scalar setting name
. For example getCalibration("cranking.rpm")
For complete list of possible calibration names (valid parameter values) and descriptions see https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/generated/value_lookup_generated.md.
setCalibration(name, value, needEvent)
Sets specified calibration setting to specified value. Fires calibration change event depending on needEvent parameter.
For example setCalibration("cranking.rpm", 900, false)
burnconfig
Schedule calibration write to flash once the engine is stopped.
findSetting(name, defaultValue)
Find User Setting with specified name and returns numeric value. Useful when script developer and script consumer are different people, also useful while Lua script editing is available only in TS.
- Parameters
name
: Variable name, as in corresponding 'name' field in configurationdefaultValue
: value to use if specified setting not located by name
isFirmwareError
Returns true if ECU is in state of critical/fatal error.
Engine Control
startCrankingEngine()
Start cranking as if physical start button was tapped.
stopEngine()
isEngineStopRequested()
returns true if engine stop was requested by either Lua or start/stop button within the last five seconds
setSparkSkipRatio(ratio)
setSparkSkipRatio(0) to skip 0% of the ignition events, i.e. no skipping setSparkSkipRatio(0.5) would skip half of ignition events. We never skip two consecutive ignitions. #torque
setSparkHardSkipRatio(ratio)
setSparkHardSkipRatio(0) to skip 0% of the ignition events, i.e. no skipping setSparkHardSkipRatio(0.75) would skip 75% of ignition events. #torque
setIdleAdd(percent)
Percent to add to idle (incl. open loop).
setFuelAdd(amount)
Sorry not finished :(
Amount of fuel mass to add to injection, scaled by fuel multiplier (setFuelMult()
); initially 0.
setFuelMult(coeff)
Sorry not finished :(
Amount to scale added fuel mass by; initially 1.0;
setBoostTargetAdd(amount)
Additive for closed loop target boost pressure.
setBoostTargetMult(coeff)
Multiplier for closed loop target boost pressure.
setBoostDutyAdd(amount)
Additive for open loop target boost pressure.
setTimingAdd(angle)
Use negative values to retard timing.
setTimingMult(coeff)
todo add details but ready to test! #torque
setEtbAdd(percent)
Amount of ETB to add, as a percent of the wide-open value: e.g. 10
for +10%. The value is a static amount to add to
the determined value, e.g. TPS of 5% w/ 10
results in 15% ETB. #torque
Timer
yourTimer = Timer.new();
to have a new variable of Timer type
reset
yourTimer:reset();
to reset timer
getElapsedSeconds
yourTimer:getElapsedSeconds();
to get number of seconds since timer was reset
CAN bus
enableCanTx(isEnabled)
enabled by default
use enableCanTx(false) to suppress CAN TX
txCan(bus, ID, isExt, payload)
- Parameters
- bus: hardware CAN bus index, only '1' on most rusEFI boards, '1' or '2' on Proteus
- isExt: 0 for 11 bit mode
canRxAdd(id)
canRxAdd(bus, id)
canRxAdd(id, callback)
canRxAdd(bus, id, callback)
canRxAddMask(id, mask)
canRxAddMask(bus, id, mask)
canRxAddMask(id, mask, callback)
canRxAddMask(bus, id, mask, callback)
- Parameters
- id: CAN ID to listen to.
- mask: Apply a mask to the received ID before comparing to the
id
parameter. For example, passing an id of3
and mask of 0xFF will match any frame whose last 8 bits match3
. If omitted, no masking is applied before comparison, so only a single CAN ID will be received. Use the mask to subscribe to multiple messages with similar IDs with a single call tocanRxAddMask
. - bus: Hardware CAN bus index, only '1' on most rusEFI boards, '1' or '2' on Proteus. If this parameter is omitted, messages will be received from any bus.
- callback: A the callback function to call when the specified ID is received. If this parameter is not passed, the default function
onCanRx
will be used.
Your CAN RX callback should look like this:
function onCanRx(bus, id, dlc, data)
-- Do things with CAN data!
end
SENT protocol
getSentValue(index)
TODO: document parameters, response
getSentValues(index)
TODO: document parameters, response
PID
deltaTime is measured automatically between current and previous "pid:get" invocation.
-- p, i, d, min, max
pid = Pid.new(2, 0, 0, -100, 100)
pid:setOffset(0.3)
pid:get(target, input)
pid:reset()
-- p, i, d, min, max
industrialPid = IndustrialPid.new(2, 0, 0, -100, 100)
industrialPid:setOffset(0.3)
industrialPid:setDerivativeFilterLoss(0.3)
industrialPid:setAntiwindupFreq(0.3)
industrialPid:get(target, input)
industrialPid:reset()
Utility
print(msg)
Print a line of text to the ECU's log.
- Parameters
msg
: The message to print. Pass a string or number and it will be printed to the log.
- Returns
- none
vin(index)
Return VIN setting character at specified index
- Parameters
- index: zero-based index
Usage example
Program:
n = 5.5
print('Hello Lua, number is: ' ..n)
Output:
Hello Lua, number is 5.5
setTickRate(hz)
Sets the rate at which rusEFI calls your onTick
and onCanRx
functions, in hz. On reset default is 10hz.
- Parameters
hz
: Desired tick rate, in hz. Values passed will be clamped to a minimum of 1hz, and maximum of 200hz.
- Returns
- none
mcu_standby()
Stops MCU.
interpolate(x1, y1, x2, y2, x)
Interpolates x
placing it on the line defined by (x1, y1) and (x2, y2)
findTableIndex(name)
Find table index by specified human-readable name.
table3d(tableIdx, x, y)
Looks up a value from the specified Script Table.
- Parameters
tableIdx
: Index of the table to use. Currently 4 tables are supported, so indices 1, 2, 3, and 4 are valid.x
: X-axis value to look up in the table (this is often RPM)y
: Y-axis value to look up in the table (this is often load)
- Returns
- A number representing the value looked up from the table.
findCurveIndex(name)
Finds curve index by specific curve name
curve(curveIdx, x)
Looks up a value from the specified Script Curve.
- Parameters
tableIdx
: Index of the script to use, starting from 1.x
: Axis value to look up in the table
setDebug(index, value)
Sets a debug channel to the specified value. Note: this only works when the ECU debug mode is set to Lua
.
- Parameters
index
: the index of the debug channel to set, 1 thru 7 inclusive.value
: the value to set the channel to
- Returns
- none
mcu_standby
Puts MCU into standby low current consumption mode.
Input
getSensor(name)
Reads the specified sensor. For instance getSensor("AcceleratorPedal")
- Parameters
name
: Name of the sensor to read. A list of sensor names can be found here.
- Returns
- A reading from the sensor, or
nil
if the sensor has a problem or isn't configured.
- A reading from the sensor, or
getSensorByIndex(index)
Reads the specified sensor.
- Parameters
index
: Index of the sensor to read. A list of sensor indices can be found here.
- Returns
- A reading from the sensor, or
nil
if the sensor has a problem or isn't configured.
- A reading from the sensor, or
getSensorRaw(index)
Reads the raw value from the specified sensor. For most sensors, this means the analog voltage on the relevant input pin.
- Parameters
index
: Index of the sensor to read. A list of sensor indices can be found here.
- Returns
- The raw value that yielded the sensor reading, or 0 if the sensor doesn't support raw readings, isn't configured, or has failed.
getAuxAnalog(index)
More or less like getSensorRaw but always voltage of aux analog input.
- Parameters
index
: Index of aux analog sensor to read. From 0 to 3
- Returns
- Voltage of sensor reading, or nil if sensor isn't configured.
hasSensor(index)
Checks whether a particular sensor is configured (whether it is currently valid or not).
- Parameters
index
: Index of the sensor to check. A list of sensor indices can be found here.
- Returns
- A boolean value,
true
if the sensor is configured, andfalse
if not.
- A boolean value,
getDigital(index)
Reads a digital input from the specified channel.
- Parameters
index
: The index of the digital channel to read. See table below for values.
- Returns
- A boolean value representing the state of the input pin.
true
= high voltage (above ~2 volts),false
= low voltage (below ~3 volts)
- A boolean value representing the state of the input pin.
Valid index
parameter values:
Index | Channel Name |
---|---|
0 | Clutch down switch |
1 | Clutch up switch |
2 | Brake switch |
3 | AC switch |
getAuxDigital(index)
Reads a digital input from the configurable list.
- Parameters
index
: The index of the digital pin to read. Valid values are 0 through 7, one for each of the 8 user-defined digital pins. See "Lua Digital Aux Inputs" table under "Advanced" settings tab.
- Returns
- A boolean value representing the state of the input pin.
true
= high voltage (above ~2 volts),false
= low voltage (below ~3 volts)
- A boolean value representing the state of the input pin.
readPin(pinName)
Reads physical value of arbitrary MCU pin
- Parameters
pinName
: string name of MCU pin, for examples "PD15"
Output
Not to be confused with internal logic 'Live View'/Log data points/gauges 'outputs'. Not to be confused with GPPWM feature.
selfStimulateRPM(rpm)
Positive value would start clicking injectors at specified RPM, zero value would stop self-stimulation.
startPwm(index, frequency, duty)
Initializes PWM on the specified index, starting at the specified frequency and duty cycle. The index selects which config field pin to use, see "Lua PWM Outputs" page in TunerStudio.
- Parameters
index
: The index of the PWM channel to start. Valid values are 0 through 7, one for each of the 8 channels.frequency
: Initial frequency of the output, in hertz (cycles per second). Valid values are between 1 and 1000hz.duty
: Initial duty cycle of the output.0.0
= fully off, and1.0
= fully on.0.25
= on 25% of the time, off 75% of the time.
- Returns
- none
setPwmDuty(index, duty)
Set the duty cycle of the specified PWM channel.
- Parameters
index
: The index of the PWM channel to set. Valid values are 0 through 7, one for each of the 8 channels.duty
: Desired duty cycle of the output.0.0
= fully off, and1.0
= fully on.0.25
= on 25% of the time, off 75% of the time.
- Returns
- none
setPwmFreq(index, frequency)
- Parameters
index
: The index of the PWM channel to set.frequency
: Initial frequency of the output, in hertz (cycles per second). Valid values are between 1 and 1000hz.
- Returns
- none
setLuaGauge(index, value)
In an ideal world one would be using Sensor.new("LuaGauge1") but looks like that's not the way at the moment :(
- Parameters
index
: The index of the Lua gauge to set. Valid indices are '1' and '2'.value
: Desired gauge value.
- Returns
- none
setDacVoltage(index, value)
Not enabled on most boards since most boards were not developer with DAC in mind! See https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/examples/dac.txt for more info.
Misc console commands
luamemory
luareset
Examples
Read VSS from CANbus for gear detection see honda-bcm.txt
timer
t = Timer.new();
timingAdd = 0;
function onTick()
auxV = getAuxAnalog(0)
tps = getSensor("TPS")
-- todo: check for NIL value which is a sign of analog input not assigned in TS
if auxV > 2 then
t:reset();
end
val = t:getElapsedSeconds();
if t:getElapsedSeconds() < 3 then
timingAdd = 10;
else
timingAdd = 0;
end
setTimingAdd(timingAdd)
print('Hello analog ' .. auxV .. " " .. val)
end
PWM
-- index 0, 100Hz, zero duty initially
startPwm(0, 100, 0)
function onTick()
enable_pump = getSensor("RPM") > 700 and getSensor("BatteryVoltage") > 13 and getSensor("VehicleSpeed") <60
-- lua does not have ternary ? : operator, this here means "1 if enable_pump and 0 otherwise"
setPwmDuty(0, enable_pump and 1 or 0)
end
CAN transmit
function onTick()
tps = getSensor("CLT")
print('TPS ' .. tps)
voltage0 = getSensor("aux0")
txPayload = {}
// first byte: integer part, would be converted to int
txPayload[1] = voltage0
// second byte: fractional part, would be converted to int, overflow would be ignored
txPayload[2] = voltage0 * 256;
txCan(1, 0x600, 1, txPayload)
end
set sensor value
A list of sensor names can be found here.
-- make sure physical input is NOT configured to avoid 'one was already registered' conflict
vssSensor = Sensor.new("VehicleSpeed")
-- any value would be considered valid for three seconds
vssSensor:setTimeout(3000)
function onTick()
injectedVssValue = 123.4;
vssSensor : set(injectedVssValue)
-- here we would read the value we have just injected into the sensor.
valFromSensor = getSensor("VehicleSpeed")
-- we expect output to be "VSS 123.4"
print ("VSS " .. valFromSensor)
end
CAN receive
canRxAdd(0x500)
canRxAdd(0x570)
function onCanRx(bus, id, dlc, data)
print('got CAN id=' ..id ..' dlc=' ..dlc)
if id == 0x500 then
-- Check can state of BCM
canState = data[1]
end
if id == 0x570 then
mcu_standby()
end
end
function decimalToHex(num)
if num == 0 then
return '0'
end
local hexstr = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, "A", "B", "C", "D", "E", "F" }
local result = ""
while num > 0 do
local n = num % 16
result = hexstr[n + 1] ..result
num = math.floor(num / 16)
end
return result
end
function print_array(arr)
local str = ""
local index = 1
while arr[index] ~= nil do
str = str.." "..decimalToHex(arr[index])
index = index + 1
end
return str
end
table
tableIndex = findTableIndex("duty")
TurbochargerSpeed = getSensor("TurbochargerSpeed")
tps = getSensor("Tps1")
dutyCycle = table3d(tableIndex, TurbochargerSpeed, tps)
sparkCutCurve = findCurveIndex("sparkcut")
sparkCutByTorque = curve(sparkCutCurve, torque)
See also
BMW iDrive
See https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/examples/bmw-idrive.txt
More examples at https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/examples/
See also a library for CAN data manipulation https://github.com/rusefi/rusefi/blob/master/firmware/controllers/lua/lua_lib.h
See also test driven development approach https://github.com/rusefi/rusefi/tree/master/unit_tests/tests/lua