Pressure advance tuning with conditional G-code

Schmart

@t3p3tony Apologies, I was indeed referring to the markdown representation of G-code in the forum. Fortunately, the firmware itself handles comments with single quotes without any issue. @o_lampe I wasn't aware of the 'perl' option, I will try this when I'm back home!

Schmart

@o_lampe @T3P3Tony Tried the 'perl' code block in the markdown of my original post, and changed line 100 briefly to contain "haven't" instead of "have not". But the result doesn't look better then.

Also in the fragments below the rendering issue can be reproduced; notice the "{1}" at line 11.

; Make an inventory of axes that haven't yet been homed
 var axes = ""
 echo "Total number of axes: " ^ {#move.axes}
 while {iterations < #move.axes}
   if {!move.axes[iterations].homed}
     set var.axes = {var.axes ^ move.axes[iterations].letter}
  
 ; Home applicable axes
 echo "Axes to be homed: " ^ var.axes
 G28 {var.axes}

Versus the exact same perl code block with "have not":

; Make an inventory of axes that have not yet been homed
 var axes = ""
 echo "Total number of axes: " ^ {#move.axes}
 while {iterations < #move.axes}
   if {!move.axes[iterations].homed}
     set var.axes = {var.axes ^ move.axes[iterations].letter}
  
 ; Home applicable axes
 echo "Axes to be homed: " ^ var.axes
 G28 {var.axes}

Schmart

@t3p3tony said in Pressure advance tuning with conditional G-code:

This is really very cool. Its awesome to see the concept of gcode meta commands used in this way. I have logged the wishlist items.

Thank you for that, by the way! ️

T3P3Tony

This post is deleted!

T3P3Tony

@t3p3tony

ok so with perl:

; Make an inventory of axes that haven't yet been homed
 var axes = ""
 echo "Total number of axes: " ^ {#move.axes}
 while {iterations < #move.axes}
   if {!move.axes[iterations].homed}
     set var.axes = {var.axes ^ move.axes[iterations].letter}
  
 ; Home applicable axes
 echo "Axes to be homed: " ^ var.axes
 G28 {var.axes}

without perl

; Make an inventory of axes that haven't yet been homed
 var axes = ""
 echo "Total number of axes: " ^ {#move.axes}
 while {iterations < #move.axes}
   if {!move.axes[iterations].homed}
     set var.axes = {var.axes ^ move.axes[iterations].letter}
  
 ; Home applicable axes
 echo "Axes to be homed: " ^ var.axes
 G28 {var.axes}

T3P3Tony

so i can't recreate it with that snippet is if use no specified syntax highlighting.

Schmart

@t3p3tony Editing on my phone is terrible because I can't get out of preview mode anymore, but I've managed to put the entire code in a code block without specifying any language, and changed line 100 to use "haven't". Then on line 106, 110, 114 and 117, I'm spotting some issues.

; This macro generates a test print to determine the best pressure advance factor (M572 S-parameter)
; It uses the test print described in this forum post:
; https://forum.duet3d.com/topic/6698/pressure-advance-calibration

; Author: Schmart

; WARNING: all dimensions, size units and speeds are in mm and mm/s

; Reference for conditional G-code:
; - https://duet3d.dozuki.com/Wiki/GCode_Meta_Commands

; Wishes for conditional G-code:
; - Canceling or stopping running conditional G-code
; - Simulation; logging what commands would be executed/generated without actually executing them
; - Dumping the variables (names and values) in a macro, perhaps also treating variable in a meta-way, e.g. {#var} for count, {var[0].name} and {var['layer_height'].value}
; - Assigning an object or array to a variable. E.g. var axis = move.axes[0]; echo {var.axis.letter}
; - Custom subroutine/function definition, e.g. def print_line(var a, var b)
; - ceiling(), pow() and sq() functions

; TODO:
; - Many optimizations still remaining
; - Perhaps the most important variables (bed and print temperature, filament diameter, extrusion multiplier, PA stepping)
;   can be made into macro parameters, e.g. M98 P"0:/macros/4 - Print Tuning/Pressure Advance" B40 P204 D1.75 X0.95 S0.02 P0.002

; Starting value for pressure advance
var pa_start = 0.0
; Pressure advance increment for each (whole) millimeter print height
; e.g. if var.height = 20, var.pa_start = 0.1 and var.pa_stepping = 0.004, then
; the PA test range is from 0.1 to (0.1 + 20 * 0.004) => 0.1 to 0.18.
var pa_stepping = 0.01
; The extruder to apply the pressure advance factor to
var pa_extruder = 0
; These values specify the center of the print bed
; The default bed center is at (0,0)
var x_center = 0
var y_center = 0
; Print temperatures
var print_temperature = 205
var standby_temperature = 120
var bed_temperature = 40
; Height of the test print
var height = 20
var layer_height = 0.20
; Number of fast segments
var fast_segments = 3
; Slow segments are at the beginning and the end, and in between fast segments, e.g. SLOW FAST SLOW FAST SLOW
var slow_segment_length = 10
var fast_segment_length = 20
; Definition of speeds
var first_layer_speed = 20
var travel_speed = 80
var fast_segment_speed = 60
var slow_segment_speed = 10
; Number of perimeters around the object as a stable base
var skirt_loops = 6
; Height of the skirt in layers
var skirt_layers = 2
; The tool number to print with
var tool_number = 0
; Extrusion width is calculated here, but can also be set with a literal value
; Note that 1.05 and 1.125 are common factors that result in 0.42mm or 0.45mm width respectively
var nozzle_bore_diameter = 0.40
var extrusion_width = {var.nozzle_bore_diameter * 1.125}
var filament_diameter = 1.78
var extrusion_multiplier = 0.93
; Firmware retraction settings
var retract_length = 0.5
var retract_restart_length = 0
var retract_speed = 40
var deretract_speed = 40
var retract_z_lift = 0

; Flow math
var filament_flow = {pi * var.filament_diameter * var.filament_diameter / 4}
var regular_flow = {(var.extrusion_width - var.layer_height) * var.layer_height + pi * var.layer_height * var.layer_height / 4}
var bridge_flow = {pi * var.nozzle_bore_diameter * var.nozzle_bore_diameter / 4}
var line_spacing = {var.extrusion_width - var.layer_height * (1 - pi / 4)}
var regular_flow_ratio = { var.extrusion_multiplier * var.regular_flow / var.filament_flow}
var purge_line_flow_ratio = { 2.0 * var.regular_flow_ratio }

echo "extrusion_width: " ^ var.extrusion_width
echo "layer_height: " ^ var.layer_height
echo "filament_flow: " ^ var.filament_flow
echo "bridge_flow: " ^ var.bridge_flow
echo "regular_flow: " ^ var.regular_flow
echo "line_spacing: " ^ var.line_spacing
echo "regular_flow_ratio: " ^ var.regular_flow_ratio

;M37 S1 ; Enter simulation mode

; Set firmware retraction
M207 S{var.retract_length} R{var.retract_restart_length} F{60 * var.retract_speed} T{60 * var.deretract_speed} Z{var.retract_z_lift}

T{var.tool_number} ; Select tool
M106 S0 ; Turn off part cooling fan
M568 P{var.tool_number} S{var.print_temperature} R{var.standby_temperature} A1 ; Set tool to standby temperature
M190 S{var.bed_temperature} ; Wait for bed temperature to reach setpoint
M116 P{var.tool_number} ; Wait for temperatures associated with the selected tool to be reached

; Make an inventory of axes that haven't yet been homed
var axes = ""
echo "Total number of axes: " ^ {#move.axes}
while {iterations < #move.axes}
  if {!move.axes[iterations].homed}
    set var.axes = {var.axes ^ move.axes[iterations].letter}

; Home applicable axes
echo "Axes to be homed: " ^ var.axes
G28 {var.axes}

;G28 XYZ ; Home the X, Y and Z axes
;G28 XY ; Home the X and Y axes
;G28 Z ; Home the Z axis

G21 ; Set units to millimeters
M83 ; Use relative distances for extrusion

; Calculate object width
var width = {var.fast_segments * var.fast_segment_length + (1 + var.fast_segments) * var.slow_segment_length}
; Calculate starting coordinates and other constant(s)
var x_start = {var.x_center - 0.5 * var.width + var.skirt_loops * var.line_spacing}
var y_start = {var.y_center - 0.5 * var.line_spacing + var.skirt_loops * var.line_spacing}
var travel_feedrate = {60 * var.travel_speed}
var first_layer_feedrate = {60 * var.first_layer_speed}

; Absolute position for purge line in X and Y space, 50 mm behind model
G90 ; Use absolute coordinates
G1 X{var.x_start} Y{var.y_start + 50} F{var.travel_feedrate}

; Set heater to final temperature and wait
M568 A2
M116 P{var.tool_number}

; Absolute position of nozzle at first layer height
G1 Z{var.layer_height} F{var.travel_feedrate}

; Relatively print two fat purge lines
G91 ; Switch to relative coordinates
G1 X{var.width} E{var.width * var.purge_line_flow_ratio} F{var.first_layer_feedrate}
G1 Y{-(2 * var.line_spacing)} F{var.travel_feedrate}
G1 X{-var.width} E{var.width * var.purge_line_flow_ratio} F{var.first_layer_feedrate}

G10 ; Retract to prevent oozing

; Move to the start of the model in X, Y and Z space
; The skirt code also moves to the start, but the skirt can be disabled.
; Also, the skirt code does not set Z, and there may be no purge line for which Z is set. Safety first.
G90 ; Use absolute coordinates
G1 X{var.x_start} Y{var.y_start} Z{var.layer_height} F{var.travel_feedrate}
G91 ; Switch to relative coordinates

G11 ; Advance/unretract/deretract in preparation to print

; Routine for printing the test object
var layers = {floor(var.height / var.layer_height)}
echo "Total number of layers: " ^ var.layers

while {iterations < var.layers}
  ; Track current layer
  var layer = {iterations + 1}
  ; Current height in mm
  var z = {var.layer * var.layer_height}
  ; Calculate pressure advance factor
  var pa = {var.pa_start + floor(var.z) * var.pa_stepping}
  ; Set pressure advance
  M572 D{var.pa_extruder} S{var.pa}

  ; Output some statistics while printing
  echo "Layer " ^ iterations ^ " (" ^ {iterations + 1} ^ " of " ^ {var.layers} ^ " at " ^ {var.z} ^ "mm)"
  echo "Pressure advance: " ^ {var.pa}

  ; Pre-calculate feedrates for first layer and other layers
  var slow_segment_feedrate = {60 * (var.layer == 1 ? var.first_layer_speed : var.slow_segment_speed)}
  var fast_segment_feedrate = {60 * (var.layer == 1 ? var.first_layer_speed : var.fast_segment_speed)}

  ; Print skirt
  if {iterations < var.skirt_layers}
    G90 ; Use absolute coordinates
    ; Move to absolute XY start coordinates
    G1 X{var.x_start} Y{var.y_start} F{var.travel_feedrate}
    G91 ; Switch to relative coordinates

    ; Print all loops of the skirt
    while {iterations < var.skirt_loops}
      var skirt_loop = {var.skirt_loops - iterations}
      var x = {var.width + 2 * var.skirt_loop * var.line_spacing}
      var y = {var.line_spacing + 2 * var.skirt_loop * var.line_spacing}
      ; Print one full skirt loop
      while iterations < 2
        var direction = {iterations == 0 ? 1 : -1}
        G1 X{var.direction * var.x} E{var.x * var.regular_flow_ratio} F{var.fast_segment_feedrate}
        G1 Y{var.direction * var.y} E{var.y * var.regular_flow_ratio} F{var.fast_segment_feedrate}
      ; Travel to the start of the next skirt loop
      G1 X{var.line_spacing} Y{var.line_spacing} F{var.travel_feedrate}

  ; Print two perimeters back and forth of alternating slow and fast segments
  while iterations < 2
    var direction = {iterations == 0 ? 1 : -1}
    ; Slow starting segment (X)
    G1 X{var.direction * var.slow_segment_length} E{var.slow_segment_length * var.regular_flow_ratio} F{var.slow_segment_feedrate}
    ; Remaining fast and slow segments (X)
    while iterations < var.fast_segments
      G1 X{var.direction * var.fast_segment_length} E{var.fast_segment_length * var.regular_flow_ratio} F{var.fast_segment_feedrate}
      G1 X{var.direction * var.slow_segment_length} E{var.slow_segment_length * var.regular_flow_ratio} F{var.slow_segment_feedrate}
    ; Print the side perimeter (Y)
    G1 Y{var.direction * var.line_spacing} E{var.line_spacing * var.regular_flow_ratio} F{var.slow_segment_feedrate}

  ; Move one layer up
  G1 Z{var.layer_height} F{var.travel_feedrate}

G10 ; Retract

G91 ; Relative positioning
G1 F3000 Z20 ; Move gantry up 20mm
G90 ; Absolute positioning
G28 X ; Home X axis
;M104 S0 ; Turn off nozzle heat block
M568 P{var.tool_number} S0 R0 A2 ; Set required heater temperature off
M140 S0 ; Turn off bed
M106 S0 ; Turn off part cooling fan
M18 ; Disable stepper motors

;M37 S0 ; Leave simulation mode

T3P3Tony

@schmart ok thanks. its obviously dependent on both the syntax used and the other lines.

OwenD

@t3p3tony
Nice work! @Schmart

The forum highlighting problem is long standing
https://forum.duet3d.com/post/225020
.
Sometimes you need yo try a few different language formats to get one that works.
Try python, bash, Java, json, pascal etc

Heartleander81

Hi. I test this today but I become with the duet3 6c Board and tool board 1lc in sbc Modus a error.

What can I Do?
I have test it with .g and .gcode and as Macro

With macro I become a another error Code

izeman

I wanted to try the code as well, and it doesn't seem to work as expected. The nozzle and bed heat up, and then the heater is turned off again as it starts printing it seems.

Schmart

@heartleander81 As far as I know, the conditional G-code works in a macro only, not in a .gcode file.

The second problem I suspect is a copy error. Conditional G-code is indentation sensitive; with indented text (consistently using either spaces or tabs) you essentially define the sections that run conditionally or in a loop.

In other errors I spot that the word line in purge_line_flow_ratio was somehow replaced with the line numbers 139 and 141 the variable is used on, so perhaps something's going wrong in the process of copying the text from the forum post into the macro editor.

I've just copied the code from the first post again in my editor (VS Code) and performed a difference/diff/compare with the code in my actual printer to verify that the code in this post is sound. There's no differences that explain what I'm seeing on your end

Schmart

@izeman I'm missing text like 'Axes to be homed' in the console, so I'm assuming you had to modify the code for the topology of your printer.

Can you verify that the code still contains the T{var.tool_number} and M568 P{var.tool_number} S{var.print_temperature} R{var.standby_temperature} A1 statements? This selects the current tool, respectively sets the active and standby temperatures and requests to go to the standby temperature.

If that's still in there, according to the documentation, the M568 A2 on line 131 should use the current tool (which should be selected with T{var.tool_number}) and therefore M568 should not require the P parameter, but you can try if changing the code M568 A2 (originally on line 131) to M568 P{var.tool_number} A2 helps mitigate the error.

Heartleander81

@schmart hi.

When I write a echo for purge_line_flow_ratio become I the error on line 88 not in line 139 and line 141.
I have check it on vs code to and notepad ++ ther looks All good but doun't work

PCR

@chrishamm

Via privat chat @Heartleander81 and I tried to solve his problem.

He is using a D3 with SBC. I am using a D3M+ standalone. I sent him my macro and he tried to simulatet it. He got this error:

GetFileInfo: Cannot convert Z parameter to float (value {var.layer_height})

We both are running 3.4 B5. Could this be a DSF Problem?

@oozeBot i know you have some printer running D3 with SBC. Can you try to simulate it?

Best

Heartleander81

I have copy second time the Code from first comment.

I have the error with the line 139 and 141 but the test run now.

chrishamm

@pcr Can you please send me the full G-code file?

PCR

@chrishamm here ya goPA.g

oozeBot

Here is the console output. This was tested on a 6HC with attached SBC running 3.4b5.

After simulation:

M37 P"0:/gcodes/1636019653286-pa.g"
Error: Operation failed (Reason: ArgumentException in SimpleCode: Cannot convert Z parameter to float (value {var.layer_height}))

After upload:

Failed to get file info for 1636019653286-pa.g
Operation failed (Reason: ArgumentException in GetFileInfo: Cannot convert Z parameter to float (value {var.layer_height}))

Heartleander81

Am I correct that the SBC scans the file and since it does not find a clear layer height, the error is there? Is only a guess, since without sbc the error is apparently not there

The test run now at my printer with the 2 error line 139 and 141. Nice work.