Temperature controlled LED display

[Rushmere3D]

Hi all,

I was wondering if someone could provide some pointers on a project I want to do?

So I have an E3D toolchanger and I would like to have a strip of RGB LED's read the temp of each tool and then control/changer a section of the strip depending on it's temp, is that possible?

I was originally going to do this with an ESP32 and some code created by another toolchanger user, however they decided not to provide any support for their project and I had an issue even getting it started, so I thought I could do it via firmware instead.

Would I be right in saying I can use the object model and daemon.g file to do this? Any help would be greatly appreciated.

Thanks.

[dc42]

@rushmere3d which Duet does your toolchanger use? If it uses Duet 3 then you can achieve that with no additional hardware, just a Neopixel or DotStar LED strip.

[Rushmere3D]

@dc42 Yes sorry should have said. It's running a Duet3 6HC and 3HC.

[dc42]

@rushmere3d you can create a daemon.g file that runs as a loop. The contents should be something like this (caution: untested code!):

while true
  while iterations < #sensors.analog
    var red = sensors.analog[iterations].lastReading
    var green = 255-red
    var blue = green
    M150 R{var.red} U{var.green} B{var.blue} S10 F{min(#sensors.analog-iterations-1,1)}
  G4 S3

Adjust the colour calc, number of LEDs per sensor etc. as you with. You will find it easier to test if initially you run this as an ordinary macro instead of as daemon.g and you change the initial "while true" to "while iterations < 10".

[Rushmere3D]

@dc42 Thanks for that. So that I could learn something from this and make changes, could you explain what each part means or point me to documentation that would? Thanks.

[dc42]

@rushmere3d here are some links:

https://docs.duet3d.com/en/User_manual/Reference/Gcodes#m150-set-led-colours
https://docs.duet3d.com/en/User_manual/Reference/Gcode_meta_commands#loop

[Rushmere3D]

@dc42 So, trying to get something working today and unfortunately I just can't work it out. I get this error with your supplied code, with the first "while" set to while iterations < 10 in a macro file called LED Test.

Error: 255-redunknown value 'red' of LED Test

Could you explain what and where I need to look to understand this.

Thanks.

[OwenD]

@rushmere3d
Just a typo
Change these lines

var green = 255-red
var blue = green

to

var green = 255 - var.red
var blue = var.green

[Rushmere3D]

@owend Thanks, that error is gone.

Now I get

Error: sensors.analog[5].lastReadingreached null object before end of selector string of LED Test

I guess I need to know how to tell it to read only Sensors 1,2,3,4 (my tool thermistors). Thanks

[Rushmere3D]

Maybe I need to explain better what I would like to see.

I want a strip of LEDs say 20 in total and each 5 would represent a tool of the toolchanger.

I would like the groups of 5 LEDs to change colour based on the tools temp, so say <30°C = Green, temps between 31-80°C = Orange and temps >81°C = Red

Is something like this possible?

Thanks.

[the_K]

@rushmere3d

This is what I've got to change my the colour of my 60 neopixels strip, the first and last ones show blue or red when when when the bed and heater is above 50C and change the brightness of the chamber.

; daemeon.g
; Adafruit #1426 8 led neopixel
 M150 X3
 if heat.heaters[1].current > 50 ; temp
  M150 R255 Y5 S1 F1   	         ; Red 255 Y =Bightness 0-31 S = Number 
  M150 W255 Y5 S19 F1
  M150 W255 Y20 S20 F1
 elif heat.heaters[1].current <= 50
  M150 B255 Y5 S1 F1
  M150 W255 Y5 S19 F1
  M150 W255 Y5 S20 F1
 if heat.heaters[0].current > 50 ; temp
  M150 W255 Y2 S19 F1
  M150 R255 Y5 S1 F0 
 elif heat.heaters[0].current <= 50
  M150 W255 Y2 S19 F1
  M150 B255 Y5 S1 F0

[OwenD]

@rushmere3d said in Temperature controlled LED display:

I would like the groups of 5 LEDs to change colour based on the tools temp, so say <30°C = Green, temps between 31-80°C = Orange and temps >81°C = Red

Something like this would probably work.
I don't have LED strips to test it on, so the M150 commands may need work.
You could call this from daemon.g which runs every 10 seconds by default.

What it SHOULD do is loop through each tool and for each tool get the highest heater temperature of the heaters assigned to that tool.
Usually there's only one heater per tool, but may as well future proof.

;set_led_by_temp.gcode
; set neopixels based on heater temp
 
; define the LED (probably should be in config.g)
M150 X1 Q3000000      ; set LED type to NeoPixel and set SPI frequency to 3MHz
 
 
; adjust these variables temps to suit
var lowHeat = 45
var medHeat = 60
var highHeat = 80
var pixelsPerTool = 5
 
; create other needed variables
var thisHeater= 0
var thisHeaterTemp = 0
var upperTemp = 0
var thisTool= 0
var F=0 ;
 
 
; gather the temperatures
 
while iterations < #tools ; loop through the tools
	set var.thisTool = iterations
	set var.upperTemp = 0 ; reset the upper temp
	while iterations < #tools[var.thisTool].heaters ; loop through the heaters on each tool and get max temp
		set var.thisHeater = tools[var.thisTool].heaters[iterations]
		set var.thisHeaterTemp = heat.heaters[var.thisHeater].current
		if var.thisHeaterTemp > var.upperTemp
			set var.upperTemp = var.thisHeaterTemp
			
	; determine if there will be more commands in this loop
	if iterations = #tools - 1
		set var.F = 0
	else
		set var.F = 1
		
	; Set the group of LEDs based on the temperature
	if var.upperTemp >= var.highHeat
		M150 R255 P255 S{var.pixelsPerTool} F{var.F} ; set pixels to red
		echo "Tool ", iterations , "set to red" 
	elif var.upperTemp >= var.medHeat
		M150 R255 U128 P255 S{var.pixelsPerTool} F{var.F} ; set pixels to orange
		echo "Tool ", iterations , "set to orange"
	else
		M150 U128 P255 S{var.pixelsPerTool} F{var.F} ; set pixels to green
		echo "Tool ", iterations , "set to green"	
 

[Rushmere3D]

@owend Thanks!!! This worked perfectly

[Nightowl]

I really like all these little 'tweaks' people do to their machines!

I'm going to learn from this to control a series of neopixel LEDs to change colour depending on the spindle speed for my CNC machine, and also have 3-colour LEDs to show my machine in Safe (Green: switched on but not in use/file not loaded), Pause (Orange) and Red (Running a project).

It's all pointless, of course, because I can usually tell when the CNC is working (the noise is a good clue!) but it will help me to learn about coding!

[OwenD]

I decided to do some more work on this as a bit of a project.
I don't have any LED strips to test with as yet, but I believe this will work.

I have created two macros.
One that does all the hard work. (set_led_by_temp.gcode)
It will gradually change colours based on the values you set for LOW, MEDIUM & HIGH heat.
Above or below this values it will set a constant colour.
The brightness may also be scaled depending on how close it is to the next break point.

The other macro would be called from your slicer start code after setting the nozzle temp.
It will keep calling the first macro until the target temp is reached and then will set the LED's to white.
You could call it at the end of the print by creating a similar macro waiting for cool down.

Macro to put in start code

; set_LED_while_heating.g
 
; Parameters can be passed for Tool number and target temp
; S = target temperature 
; T = Tool number
; D = delay between checks
 
; example in Prusa slicer start code
; ####
; M568 P[current_extruder] R{"{heat.coldExtrudeTemperature+5}"} S[first_layer_temperature_0] A2 
; M98 P"set_LED_while_heating.gcode" S[first_layer_temperature_0] T[current_extruder] D3
; M116
; ###
 
var toolNumber = 0
var targetTemp = 120
var delay = 3
var heaterNumber = tools[var.toolNumber].heaters[0]
 
 
if exists(param.T)
	set var.toolNumber = param.T
if exists(param.S)
	set var.targetTemp = param.S
if exists(param.D)
	set var.delay = param.D
 
while heat.heaters[var.heaterNumber].current < var.targetTemp
	M98 P"set_led_by_temp.gcode"
	G4 S{var.delay}
 
; done heating, so set to white
M150 R255 U255 B255 W255 P255 F0 ; set pixels

Main macro

; set_led_by_temp.gcode
 
; This macro sets neopixels based on tool heater temp
; It should be called from daemon.g to achieve continual updates
; or by another macro with a loop if you only want to change colours during heatup
 
;example macro called from your slicer start code before after temps, but before M116
; #####
;while heat.heaters[1].current < 120
;    M98 P"set_led_by_temp.gcode"
;    G4 S3
; done heating, so set to white
;M150 R255 U255 B255 W255 P255 F0 ; set pixels
; #######
 
; LED strip pixel count must equal number of tools * pixels per tool 
; For multiple tools the neopixels must be daisy chained or a continuos strip
; The colour will gradually scale from one to the next.
 
; define the LED (should be in config.g as the value is remembered between calls)
;M150 X2 Q3000000      ; set LED type to NeoPixel bit banged type and set SPI frequency to 3MHz
 
var RGBW = false  ; set to true if LED is RGBW type, oherwise set to false
 
var logging = true ; set to true if you want echos to appear in console to help see what the values are.  Otherwise set false
 
; adjust these variable temps to suit requirements.
var lowTemp = 30
var medTemp = 70
var highTemp = 120
 
; brightness will be scaled between lowBrightness and highBrightness according to how close it is the max for range
; eg. between low temp and med temp
; once over high temp it will scale between high temp and max heater temp as set in config.g
; to not scale brightness, set both values the same
var lowBrightness = 100
var highBrightness = 255
 
; number of pixels on the strip that are assigned to each tool e.g first five are tool 1, second 5 are tool 2 etc
; if only one tool is used, set to total number of led's on strip
var pixelsPerTool = 5 
 
; Common RGB colours (R,G,B)
; RED -		255,0,0
; YELLOW -	255,255,0
; ORANGE -	255,165,0
; BLUE -	0,0,255
; LIME -	0,255,0
; GREEN -	0,128,0
; MAGENTA - 255,0,255
; WHITE -	255,255,255
; OFF -		0,0,0
 
 
;adjust values following to achieve desired colors for each range
; this will be so much easier when we have arrays ;-)
; all values must be integers between 0 & 255
 
; high temp values (anything over high temp  will be set to this)
var highRed = 255
var highGreen = 12
var highBlue = 40
var highWhite = 0 ; only used on RGBW type
 
;medium temp values
var midRed = 200
var midGreen = 128
var midBlue = 20
var midWhite = 40 ; only used on RGBW type
 
;low temp values
var lowRed = 0
var lowGreen = 255
var lowBlue = 0
var lowWhite = 60 ; only used on RGBW type
 
; cold temp values (anything under low temp will be set to this)
var coldRed = 0
var coldGreen = 0
var coldBlue = 255
var coldWhite = 0 ; only used on RGBW type
 
 
 
; #############################  SHOULD NOT NEED TO EDIT PAST HERE   ################################
 
; create other needed variables
var thisHeater= 0
var thisHeaterTemp = 0
var upperTemp = 0
var thisTool= 0
var F=0
var maxTemp = 0 
var brightScale = 0
var redValue = 0
var greenValue = 0
var blueValue = 0
var whiteValue = 0
var setBrightness = 0
var redScale= 0
var greenScale = 0
var blueScale = 0
var whiteScale = 0 
var lowValue = 0
var highValue = 0
 
; sanity checks
if (var.lowBrightness < 0) || (var.highBrightness > 255) || (var.highBrightness < var.lowBrightness)
	echo "Invalid brightness settings.  Must be between 0 & 255.  High must be > than low.  Setting to defaults (Low 100, high 255)"
	set var.lowBrightness = 100
	set var.highBrightness = 255
if (var.lowTemp <= 0) || (var.medTemp <= var.lowTemp) || (var.highTemp <= var.medTemp)
	echo "Invalid temp range setings - resetting to defaults (low=50, medium=130,high=180)"
	set var.lowTemp = 50
	set var.medTemp = 130
	set var.highTemp = 180
if (var.logging != true) && (var.logging != false)
	echo "Invalid logging value- must be true or false"
	set var.logging = false
	
; gather the tool temperatures
while iterations < #tools ; loop through the tools
	set var.thisTool = iterations
	set var.upperTemp = 0 ; reset the upper temp
	set var.maxTemp = 0 ; reset the max temp
	set var.lowValue = 0
	set var.highValue = 0
	while iterations < #tools[var.thisTool].heaters ; loop through the heaters on each tool and get max temp
		if var.logging = true
			echo "Checking tool", var.thisTool, "heater", iterations
		set var.thisHeater = tools[var.thisTool].heaters[iterations]
		set var.thisHeaterTemp = heat.heaters[var.thisHeater].current
		if var.logging = true
			echo "Heater", iterations, ". Temp =", var.thisHeaterTemp
		if var.thisHeaterTemp > var.upperTemp
			set var.upperTemp = var.thisHeaterTemp
			set var.maxTemp = heat.heaters[var.thisHeater].max
	if var.logging = true
		echo "Max temp of heaters is" , var.upperTemp		
	; determine if there will be more commands in this loop
	if iterations = #tools - 1
		set var.F = 0
	else
		set var.F = 1	
		
	; Set the group of LEDs based on the temperature
	
	; high temp range so just set to high temp colour values, bt scale brightness up to max heater temp
	if var.upperTemp >= var.highTemp
		set var.brightScale = (var.highBrightness - var.lowBrightness) / (var.maxTemp - var.highTemp)
		set var.setBrightness = floor((var.brightScale * (var.thisHeaterTemp - var.highTemp)) + 0.5) + var.lowBrightness ;
		set var.redValue = var.highRed ;
		set var.blueValue = var.highBlue
		set var.greenValue = var.highGreen
		set var.whiteValue = var.highWhite
		if var.logging = true
			echo "Temp is > ", var.highTemp
			echo "RGB(W) values set to -" , var.redValue, var.greenValue, var.blueValue, var.whiteValue
			echo "Brightness set to", var.setBrightness
		
		; medium range - colours will be scaled between lowtemp and medium tempas will brightness
	elif var.upperTemp >= var.medTemp
		set var.brightScale = (var.highBrightness - var.lowBrightness) / (var.highTemp - var.medTemp)
		set var.setBrightness = floor(var.brightScale * (var.thisHeaterTemp -  var.medTemp) + 0.5) + var.lowBrightness ;
 
		set var.lowValue = min(var.highRed,var.midRed)
		set var.highValue = max(var.highRed,var.midRed)
		set var.redScale = (var.highValue - var.lowValue) / (var.highTemp - var.medTemp)
 
		set var.lowValue = min(var.highGreen,var.midGreen)
		set var.highValue = max(var.highGreen,var.midGreen)		
		set var.greenScale = (var.highValue - var.lowValue) / (var.highTemp - var.medTemp)
 
		set var.lowValue = min(var.highBlue,var.midBlue)
		set var.highValue = max(var.highBlue,var.midBlue)		
		set var.blueScale = (var.highValue - var.lowValue) / (var.highTemp - var.medTemp)
 
		set var.lowValue = min(var.highWhite,var.midWhite)
		set var.highValue = max(var.highWhite,var.midWhite)		
		set var.whiteScale = (var.highValue - var.lowValue) / (var.highTemp - var.medTemp)
				
		if var.midRed < var.highRed
			set var.redValue = floor((var.redScale * (var.thisHeaterTemp - var.medTemp)) + 0.5) + var.midRed
		else
			set var.redValue = var.midRed - floor((var.redScale * (var.thisHeaterTemp - var.medTemp)) + 0.5) 
		if var.midGreen < var.highGreen
			set var.greenValue = floor((var.greenScale * (var.thisHeaterTemp - var.medTemp)) + 0.5) + var.midGreen
		else
			set var.greenValue = var.midGreen -  floor((var.greenScale * (var.thisHeaterTemp - var.medTemp)) + 0.5)
		if var.midBlue < var.highBlue
			set var.blueValue = floor((var.blueScale * (var.thisHeaterTemp - var.medTemp)) + 0.5) + var.midBlue
		else
			set var.blueValue = var.midBlue - floor((var.blueScale * (var.thisHeaterTemp - var.medTemp)) + 0.5)
		if var.midWhite < var.highWhite
			set var.whiteValue = floor((var.whiteScale * (var.thisHeaterTemp - var.medTemp)) + 0.5) + var.midWhite
		else
			set var.whiteValue = var.midWhite - floor((var.blueScale * (var.thisHeaterTemp - var.medTemp)) + 0.5)
		
		if var.logging = true
			echo "Temp is > ", var.medTemp, "but < ", var.highTemp
			echo "RGB(W) values set to -" , var.redValue, var.greenValue, var.blueValue, var.whiteValue
			echo "Brightness set to", var.setBrightness
		
		; low temp range - colours will be scaled between cold tempand medium temp range, as will brightness
	elif var.upperTemp >= var.lowTemp
		set var.brightScale = (var.highBrightness - var.lowBrightness) / (var.medTemp - var.lowTemp)
		set var.setBrightness = floor(var.brightScale * (var.thisHeaterTemp -  var.lowTemp) + 0.5) + var.lowBrightness ;
 
		set var.lowValue = min(var.midRed,var.lowRed)
		set var.highValue = max(var.midRed,var.lowRed)
		set var.redScale = (var.highValue - var.lowValue) / (var.medTemp - var.lowTemp)
 
		set var.lowValue = min(var.midGreen,var.lowGreen)
		set var.highValue = max(var.midGreen,var.lowGreen)		
		set var.greenScale = (var.highValue - var.lowValue) / (var.medTemp - var.lowTemp)
		
		set var.lowValue = min(var.midBlue,var.lowBlue)
		set var.highValue = max(var.midBlue,var.lowBlue)		
		set var.blueScale = (var.highValue - var.lowValue) / (var.medTemp - var.lowTemp)
		
		set var.lowValue = min(var.midWhite,var.lowWhite)
		set var.highValue = max(var.midWhite,var.lowWhite)		
		set var.whiteScale = (var.highValue - var.lowValue) / (var.medTemp - var.lowTemp)
		
		if var.lowRed < var.midRed
			set var.redValue = floor((var.redScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5) + var.lowRed
		else
			set var.redValue = var.lowRed - floor((var.redScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5)
			
		if var.lowGreen < var.midGreen
			set var.greenValue = floor((var.greenScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5) + var.lowGreen
		else
			set var.greenValue = var.lowGreen - floor((var.greenScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5)
			
		if var.lowBlue < var.midBlue
			set var.blueValue = floor((var.blueScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5) + var.lowBlue
		else
			set var.blueValue = var.lowBlue - floor((var.blueScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5)
 
		if var.lowWhite < var.midWhite
			set var.whiteValue = floor((var.whiteScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5) + var.lowWhite
		else
			set var.whiteValue = var.lowWhite - floor((var.whiteScale * (var.thisHeaterTemp - var.lowTemp)) + 0.5)
 
		
		if var.logging = true
			echo "Temp is > ", var.lowTemp, "but < ", var.medTemp
			echo "RGB(W) values set to -" , var.redValue, var.greenValue, var.blueValue, var.whiteValue
			echo "Brightness set to", var.setBrightness
						
	; cold temp range, so just set colour to cold value but scale brightness between zero and low temp value
	else
		set var.brightScale =   (var.highBrightness - var.lowBrightness) /(var.lowTemp - 0)
		set var.setBrightness = floor(var.brightScale * (var.thisHeaterTemp - 0) + 0.5) + var.lowBrightness ;
		set var.redValue = var.coldRed
		set var.greenValue = var.coldGreen
		set var.blueValue = var.coldBlue
		set var.whiteValue = var.coldWhite
		if var.logging = true
			echo "Temp is < ", var.lowTemp
			echo "RGB(W) values set to -" , var.redValue, var.greenValue, var.blueValue, var.whiteValue
			echo "Brightness set to", var.setBrightness
	
	; finally, set the LED strip to the desired colour and brightness
	if var.RGBW = true
		M150 R{var.redValue} U{var.greenValue} B{var.blueValue} W{var.whiteValue} P{var.setBrightness} S{var.pixelsPerTool} F{var.F} ; set pixels
	else
		M150 R{var.redValue} U{var.greenValue} B{var.blueValue} P{var.setBrightness} S{var.pixelsPerTool} F{var.F} ; set pixels
 

set_led_by_temp.gcode set_LED_while_heating.gcode

[Rushmere3D]

@owend That's awesome, I've not had a chance to try the new code yet because 1) it's still quite hot in my small workshop and 2) I don't currently use PrusaSlicer for my toolchanger so haven't changed the code for S3D yet.

But I will give it a go.

Thanks.

[Rushmere3D]

@owend

Hey, had a go at using this today and It's not quite working. Below in my start gcode for single T3 printing, bare in mind on the toolchanger homing and ABL need to be done before a tool is picked up. What's happening is it basically get's to the point where the temp has been set and heating begins but even once at temp it just sits and does nothing but cycle through checking the tools/heaters.

I have both macros in the macro folder for ref.

M104
T-1
M140 S[first_layer_bed_temperature]
;M568 P0 A2 R[standby_temperature_delta] S[first_layer_temperature] ; set active and standby temps
;M568 P1 A2 R[standby_temperature_delta] S[first_layer_temperature] ; set active and standby temps
;M568 P2 A2 R[standby_temperature_delta] S[first_layer_temperature] ; set active and standby temps
M568 P3 A2 R[standby_temperature_delta] S[first_layer_temperature] ; set active and standby temps
M98 P"/macros/set_led_while_heating.g" S[first_layer_temperature] T[current_extruder] D3
G28 ;
G29 ; enable mesh
M116

[OwenD]

@rushmere3d
I'll have a look, but probably not before the weekend

[Rushmere3D]

@owend No problem, no rush.

Shall I try the set_led_by_temp as a daemon.g? rather than being called from a macro.

Thanks for your help.

[OwenD]

@rushmere3d
You could call it in daemon.g
Perhaps set up a global variable so that you can only call it when you've set that variable to true.
So in your slicer have

set global.WarmUp = true
// set all temps etc
// do homing
Set global.WarmUp = false

Then in daemon.g

If global.Warmup= true
M98 P"path-to-macro.g"