documents:de4000:de4000script [Documentation Wiki]

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DE4000 Lua Script API

create_param("index",default,"catergory","description")

creates a user configurable parameter
parameter is stored as index,
default value(If not changed by user) is default
parameters will be grouped on the Global/Params page by category
description is text to describe the parameter to the user

Example:

create_param("NumEngCyl",8,"Engine Params","Num. of Engine Cylinders")

get_channel_val(terminal,channel)

returns current value of analog input channel on terminal module terminal
return value type is numeric

Example:

local sp = get_channel_val(1,5)

reads value of Suction Pressure from Terminal Module #1 , Input #5

get_gbl("index",default)

returns global config setting stored under index or returns default if not defined

note: get_gbl is used to retrieve global CONFIGURATION settings that are typically set when the system is configured and do not change as the system is running. If you want to set and retrieve global STATUS variables use the get_sGbl() and set_sGbl() functions >If you want to create and read virtual channels use the set_sVirt() and get_sVirt() functions.

Example:

local nt = get_gbl("NumTerm",1)

gets the number of terminal boards installed in the system

get_param("index")

return either the default value or the user configured value of the parameter index

Example:

get_param("NumEngCyl")

>gets the configured parameter for number of engine cylinders

get_rpm(channel)

reads the RPM input channel in units of revolutions per minute

note: valid channel numbers are 1 - 10(2 channels per board, up to 5 terminal boards)

Each Terminal Module has 2 RPM inputs (RPM1 and RPM2)

Terminal Module #1 RPM channels are 1,2
Terminal Module #2 RPM channels are 3,4
Terminal Module #3 RPM channels are 5,6
Terminal Module #4 RPM channels are 7,8
Terminal Module #5 RPM channels are 9,10

Example:

local engineRPM = get_rpm(1)
local turboRPM = get_rpm(6)

Read RPM1 channel from terminal module #1 and read RPM2 channel from Terminal module #3

get_sGbl("index", default)

If index is defined in the global status table then it returns the value associated with index
If index is not defined and optional default is provided then returns default

>note: It is recommended to always provide a default value when using this function

Example:

local cp = get_sGbl("calculatedPressure",0)

get the previously stored value "calculatedPressure", Returns 0 if not found.

get_state()

returns the current engine state(possible values currently 0 - 10)

Example:

local engineState = get_state()
if engineState > 7 then
    set_timer("WarmupTimer",1000)
end

get_sVirt("index")

returns the value of virtual channel index or returns default if the virtual channel does not exist.

Example:

local tl = get_sGbl("timeLimit")
local et = get_sVirt("ElapsedTime",0)
if et > tl then
    set_sGbl("timeExceeded",true)
else
    set_sGbl("timeExceeded",false)
end

>Gets the value of virtual channel ElapsedTime and set value of status global "timeExceeded" if ElapsedTime is greater than status global "timeLimit"

get_time()

returns the UNIX "epoch" time (Defined as the number of seconds elapsed since Jan 1, 1970)

Example:

local startTime = get_sGbl("startTime",0)
if startTime == 0 then
    local currentTime = get_time()
    startTime = currentTime
    set_sGbl("startTime",currentTime)
end
local et = get_time() - startTime
set_sVirt("ElapsedTime",et)

>Stores current time if first time through, otherwise calculate elapsed time

get_timer("index")

returns 1 or 2 values
First return value(Boolean) is true if timer is active(counting down) or false if timer is expired or has not been set yet
Second return value is the number of seconds remaining or -1 if timer is not active or has not been set yet

Example:

if not get_timer("myTimer") then
    set_sGbl("timedOut",true)
else
    set_sGbl("timedOut",false)
end

if timer is expired, then set global status "timedOut" to true

local active,remaining = get_timer("myTimer")
if not active then
    set_sVirt("timeRemaining","Expired")
else
    set_sVirt("timeRemaining",remaining)
end

getStateLabel(state)

return the label for the engine state corresponding to the parameter state

Example:

local stateLabel = getStateLabel(get_state())
local active, remaining = get_timer("myTimer")
if remaining > 0 then
    stateLabel == StateLabel.." "..remaining
end
set_sVirt("Countdown",stateLabel)

set_sGbl("index",value)

store value in the global status table under index
value can be a number or string but if storing a boolean use the tostring() function

Example:

local mpe = false
local sp = get_channel_val(1,5)
if sp > 15 then
    mpe = true
end
set_sGbl("minPressureExceeded",tostring(mpe))

store boolean value minPressureExceeded

set_sVirt("index",value)

sets a virtual status channel with channel name index

Note: Once you create a virtual channel, you can add that channel to the dashboard using the channel name index

Example:

local sp = get_channel_val(1,5) --suction pressure
local dp = get_channel_val(1,6) --discharge pressure
local diffPress = dp - sp
set_sVirt("SuctDischDiff",diffPress)

calculate the differential between suction and discharge pressure and assign to virtual channel

set_timer("index",secs)

activate timer index and set countdown time to secs

Example:

set_timer("myTimer",300)

create timer myTimer and start countdown time to 300 seconds