Monthly Archives: September 2022

Misc: MKS Monster8 Board Configuration with Marlin for Ashtar K & C

by · published Technology , , ,

Update:

  • 2022/11/20: Linux DFU upload details added
  • 2022/09/19: adding Ashtar C M503 dump beside Ashtar K
  • 2022/08/24: extending with part cooler fan and extruder fan connection
  • 2022/08/14: starting with the notes

Introduction

MKS Monster8 V1.0 board

These are just my notes for configuring Makerbase (MKS) Monster8 V1.0 for Ashtar K and Ashtar C:

  • STM32M407VET6 (ARM Cortex M4), 168MHz, 512KB Flash, 192KB RAM
  • 8 stepper drivers TMC2209, configured in UART mode
  • MKS MINI 12864 V3 display (the “V3” is relevant)
  • 12V power in/out
  • 3 hotends & bed heating
  • Price ~EUR 55 (2022/08) incl. 8 stepper drivers TMC 2209 and 12864 display

Pros:

  • cost effective, EUR 55 (2022/08) incl. 8x TMC 2209 stepper drivers and 12864 display
  • 8 stepper drivers: e.g. X, Y, Z1/Z2 (on-board splitter) and 5 extruders (e.g. E0, E1, E2, E3, E4 – but only 3 hotends possible)
  • TMC 2208 or TMC 2209 silent drivers
  • good connectors on board, clean setup
  • github with Marlin source (partially preconfigured) for Arduino*) & PlatformIO

Cons:

  • no RepRapFirmware
  • no Wifi (the V2.0 version has optional Wifi board to attach)
  • no Ethernet
  • requires Marlin with PlatformIO (tedious to configure, recompiling required, reupload)
  • limited documentation: actual details are scattered around

Stepper Motor UART Mode

As first putting in the jumpers on all the driver sockets, in my case I choose UART mode for each one of the 8 drivers:

Marlin with Arduino vs PlatformIO

As of 2022/08, it seems Arduino is no longer able to compile Marlin-2.x (various compile errors within Arduino), at least with this board and everybody moved on the PlatformIO, which really surprised me.

PlatformIO CLI

As of 2022/08 there is no Linux GUI for PlatformIO but only PlatformIO CLI, but it’s simple enough:

pip3 install platformio

Download

As next download the firmware, Marlin 2.0.x source from github:

git clone https://github.com/makerbase-mks/MKS-Monster8/

Building

By default the board is configured for Voron 2.4 CoreXY, with 3x Z motors and Z probing in the midst of the bed and other things, so I had to edit Marlin/Configuration.h:

  • #define MACHINE_UUID "..." (use online generator to generate one)
  • #define CUSTOM_MACHINE_NAME "Ashtar K #x L8", given Lead 8×8 are used
  • #define LINEAR_AXES 3
  • #define EXTRUDERS 1 (or 2, 3 max)
  • comment out //#define PREVENT_COLD_EXTRUSION needed for calibration
  • comment out //define COREXY
  • define [XYZ]_DRIVER_TYPE and E[012]_DRIVER_TYPE
  • #define DEFAULT_AXIS_STEPS_PER_UNIT aren’t that important, as one can define it with M92 and M500 saving to EEPROM
  • comment out //#define Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN
  • test motors regarding #define INVERT_[XYZ]_DIR true or false
  • test motors regarding #define INVERT_E[012]_DIR true or false
  • #define [XYZ]_HOME_DIR -1
  • #define X_BED_SIZE 380
  • #define Y_BED_SIZE 300
  • #define Z_MAX_POS 330

and Configuration_adv.h:

  • #define NUM_Z_STEPPER_DRIVERS 1 even when two Z-stepper motors are attached
  • if you want an automatic E0 fan which turns on only when nozzle is heated: #define E0_AUTO_FAN_PIN PA1 and attach extruder fan (watch polarity) on FAN1/J12 connector

once those changes are made, build the firmware:

cd marlin\ firmware/MKS_MONSTER_Marlin-2.0.x/Marlin-2.0.x/
platformio run

After a short while (~1min) it should finish successfully (if not, edit files).

Firmware Installation

SD Card Firmware Update

Use a SD card, e.g. 8GB with simple FAT filesytem, and copy .pio/build/mks_monster8_usb_flash_drive/firmware.bin and mks_monster8.bin on the SDcard.

Insert the SD card into the Monster8 board next to the USB connector, and turn off and on the board (power cycle) – wait 5-10 seconds so the new firmware is installed, then the display should show the Marlin splashscreen eventually, and the board becomes available as USB device, in my case as /dev/ttyACM0 on Linux Ubuntu 20.04 LTS.

DFU Util Firmware Update

  • connect board with USB cable and optionally select POWER USB (via jumper)
  • power cycle board (e.g. via USB cable) while you push BOOT 0 button in the center of the board briefly (~2 secs)
  • the device will appear as a new USB device

Linux: install apt install dfu-util and then

% sudo dfu-util -a 0 -s 0x0800C000:leave -D .pio/build/mks_monster8_usb_flash_drive/mks_monster8.bin -d 0483:df11
dfu-util 0.9

Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to http://sourceforge.net/p/dfu-util/tickets/

dfu-util: Invalid DFU suffix signature
dfu-util: A valid DFU suffix will be required in a future dfu-util release!!!
Opening DFU capable USB device...
ID 0483:df11
Run-time device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Setting #0 ...
Determining device status: state = dfuERROR, status = 10
dfuERROR, clearing status
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 2048
DfuSe interface name: "Internal Flash  "
Downloading to address = 0x0800c000, size = 178820
Download        [=========================] 100%       178820 bytes
Download done.
File downloaded successfully
Transitioning to dfuMANIFEST state
%

M503 Dump for Ashtar K

Ashtar K with 300×300 bed, single extruder:

> M503
-----
echo:  G21    ; Units in mm (mm)
echo:  M149 C ; Units in Celsius

echo:; Filament settings: Disabled
echo:  M200 S0 D1.75
echo:; Steps per unit:
echo: M92 X100.00 Y100.00 Z400.00 E95.00
echo:; Maximum feedrates (units/s):
echo:  M203 X300.00 Y300.00 Z5.00 E25.00
echo:; Maximum Acceleration (units/s2):
echo:  M201 X2500.00 Y2500.00 Z100.00 E5000.00
echo:; Acceleration (units/s2): P<print_accel> R<retract_accel> T<travel_accel>
echo:  M204 P3000.00 R3000.00 T3000.00
echo:; Advanced: B<min_segment_time_us> S<min_feedrate> T<min_travel_feedrate> X<max_x_jerk> Y<max_y_jerk> Z<max_z_jerk> E<max_e_jerk>
echo:  M205 B20000.00 S0.00 T0.00 X10.00 Y10.00 Z0.30 E5.00
echo:; Home offset:
echo:  M206 X-35.00 Y-3.00 Z0.15
echo:; Material heatup parameters:
echo:  M145 S0 H180.00 B70.00 F0
echo:  M145 S1 H240.00 B110.00 F0
echo:; PID settings:
echo:  M301 P22.20 I1.08 D114.00
echo:; LCD Contrast:
echo:  M250 C255  
echo:; Power-Loss Recovery:
echo:  M413 S1
echo:; Stepper driver current:
echo:  M906 X500 Y500 Z700
echo:  M906 T0 E500

echo:; Driver stepping mode:
echo:  M569 S1 X Y Z
echo:  M569 S1 T0 E
ok
>

M503 Dump for Ashtar C

Ashtar C with 400×400 bed, 3 extruders with single nozzle:

> M503
-----
echo:  G21    ; Units in mm (mm)
echo:  M149 C ; Units in Celsius

echo:; Filament settings: Disabled
echo:  M200 T0 D1.75
echo:  M200 T1 D1.75
echo:  M200 T2 D1.75
echo:  M200 S0
echo:; Steps per unit:
echo: M92 X100.00 Y100.00 Z3200.00 E102.00
echo:; Maximum feedrates (units/s):
echo:  M203 X500.00 Y500.00 Z2.00 E120.00
echo:; Maximum Acceleration (units/s2):
echo:  M201 X9000.00 Y9000.00 Z50.00 E10000.00
echo:; Acceleration (units/s2): P<print_accel> R<retract_accel> T<travel_accel>
echo:  M204 P1500.00 R1500.00 T1500.00
echo:; Advanced: B<min_segment_time_us> S<min_feedrate> T<min_travel_feedrate> X<max_x_jerk> Y<max_y_jerk> Z<max_z_jerk> E<max_e_jerk>
echo:  M205 B20000.00 S0.00 T0.00 X10.00 Y10.00 Z0.20 E2.50
echo:; Home offset:
echo:  M206 X0.00 Y-5.00 Z0.15
echo:; Material heatup parameters:
echo:  M145 S0 H180.00 B70.00 F0
echo:  M145 S1 H240.00 B110.00 F0
echo:; PID settings:
echo:  M301 P22.20 I1.08 D114.00
echo:; LCD Contrast:
echo:  M250 C255
echo:; Power-Loss Recovery:
echo:  M413 S1
echo:; Stepper driver current:
echo:  M906 X700 Y700 Z1000
echo:  M906 T0 E700
echo:  M906 T1 E700
echo:  M906 T2 E700

echo:; Driver stepping mode:
echo:  M569 S1 X Y Z
echo:  M569 S1 T0 E
echo:  M569 S1 T1 E
echo:  M569 S1 T2 E
echo:; Tool-changing:
echo: Z2.00
ok
>

Fans

Part cooler fan is plugged into FAN0/J11, and if you enabled extruder fan (temperature dependent), plug it in FAN1/J12.

Part Cooler Fan (FAN0/J11) and Extruder Fan (temperature sensitive) FAN1/J12
  • Part Cooler Fan (FAN0): cools the extruded filament, the filament which becomes the part you print
  • Extruder Fan (FAN1): cools the heatsink near the heatbreak, when attached to FAN1/J12 it only runs when the hotend is hotter than 50C° as defined in Marlin.

The jumpers are needed next to the fan connectors to define the voltage, either Vin (left) which is 12V-24V depending on the power input of the board, or 12V (middle) or 5V (right).

MKS Monster8 V1.0 Pins
MKS Monster8 V2.0 Pins

Multiple Materials/Colors

With 8 stepper drivers one is able to run:

  • 3+1x motors for X, Y, Z(2)
  • 5x extruders (colors or materials), the board supports 3 hotends (3 different temperatures)

Monster8 V1.0 vs V2.0

The boards differ in physical layout such as connectors, but the firmware is the same, incl. the pin for the hotend cooler fan (which switches on conditionally when hotend heats up).

Update V2.0

Board Comparison 2022

As of 2022 (I intend to update this) following boards are suitable for my cases:

MKS Monster8 V1.0/V2.0 & 12864 displayMellow Fly Super8 V1.2 & 12864 displayDuet 3 Mini 5+ & Duet 3 Mini 2+Duet 3 MB 6HC & Duet 3 Expansion 3HC
Price55 EUR80 EUR155 EUR (120+35)385 EUR (255+130)
Stepper Drivers887 (5+2)9 (6+3)
Stepper Connectors9 (dual Z)879
Hotends345 (2+3)6 (3+3)
USBYES (USB-C)YES (USB-C)YES (MicroUSB)YES (MicroUSB)
WIFI– / YES3)YESYES1)YES1)
Ethernet––YES1)YES1)
FirmwareMarlin 2.xMarlin 2.x
RepRapFirmware 3.4.x		RepRapFirmwareRepRapFirmware

Alternatively, there are Duet 2 & 3 clones available on the market:

Duet 2 WIFI CloneDuet 2 WIFI OriginalDuet 3 6HC FYSETC Clone with Duet 3 3HCDuet 3 6HC Original with Duet 3 3HC
Price30-50 EUR2)175-185 EUR1) 225 EUR (150+75)385 EUR (255+130)
Stepper Drivers559 (6+3)9 (6+3)
Stepper Connectors6699
Hotends227 (4+3)6 (3+3)
USBYES (MicroUSB)YES (MicroUSB)YES (MicroUSB)YES (MicroUSB)
WIFIYESYES1)–YES1)
Ethernet–YES1)
YES
YES1)
FirmwareRepRapFirmwareRepRapFirmwareRepRapFirmwareRepRapFirmware
  1. either WIFI or Ethernet
  2. without or with display
  3. MKS Monster8 V2.0 has Wifi module option

As of 2022, RepRapFirmware has become quasi standard in professional level 3D printing; while a lot of people run Klipper & Marlin together I can’t see the point doing this*) but rather have a more capable microcontroller like the Duet boards have to run the printer and manage WIFI / Ethernet at the same time. The only reason to run Klipper on a Single Board Computer (SBC) setup like Raspberry Pi is cost and enhance simple microcontrollers functionality this way.

MarlinKlipper & MarlinRepRapFirmware with Duet
CPUs1x Simple Microntroller1x SBC + 1x Simple Microcontroller1x Capable Microcontroller
ConnectivityUSB onlyUSB, Ethernet and/or WIFIUSB and Ethernet or WIFI
Configuration3x .h files, recompiling requiredsingle .cfg filesingle .g file**)
Boot Time3sKlipper 30s, Marlin 3s3s

*) running different kinematics on the SBC converting G-code on the fly might be a reason
**) multiple .g file can be used optionally

If you are cheap, buy the Duet clones, if you want to support Open Source and Open Hardware community, buy from Duet3d.com direct, pricing is +45% of the clone prices, whereas the Duet resellers add another +15% (Clone: EUR 150, Duet3d.com: 220 EUR, Reseller 255 EUR)

RepRapFirmware: Mind the SD Card

Whether to run an original Duet board or a clone, one thing though one might pay attention to is the SD card, it is the weakest link as far I can tell:

  • SD card needs to be present at all time to provide configuration
  • SD card is not written regularly to unless the logging is enabled

After power-cycling the board, as it was in a strange state no longer responding to G-code properly, the display remained blank, no response to G0/G1 – after investigation it turned out, a single file vanished from the SD card: config.g – the main configuration file, and that is bizarre. The board appeared to be broken, when in truth, the SD card came to its end of life of operating reliably already after only ~1.5 years. The SD card was the one originally shipped with. In this light, a Marlin-based board requiring no SD card being present operates more reliable, unless one uses an industrial grade SD card.

References

Misc: Mellow Fly Super8 V1.2 with RepRapFirmware for Ashtar C & D

by · published Technology , , ,

Updates:

  • 2022/08/25: extending for more details of config.g limit switches
  • 2022/08/16: starting notes

Introduction

Fly Super8 V1.2 board

I have become a big fan of Duet3 boards running RepRapFirmware, and as I was looking for a suitable board, and I came across Mellow Fly Super8 V1.2 board, 8 steppers TMC 2209, and 4 possible hotends.

  • STM42F407ZGT6 (ARM Cortex-M4), 168MHz, 1MB Flash, 192KB RAM
  • 8 stepper drivers TMC2209, configured in UART mode
    • 3x X, Y, Z(2 using splitter)
    • 5x extruders
  • Fly MINI 12864 display
  • 12V power in/out
  • 4 hotends & bed heating
  • Price ~EUR 80 (2022/08) incl. 8 stepper drivers TMC 2209 and 12864 display

Pros:

  • cost effective, EUR 80 (2022/08) with 8x stepper drivers TMC 2209 and 12864 display
  • runs RepRapFirmware
    • most configuration is done with .g files using G-code notion
    • only new non-supported kinematics require recompiling
  • USB & Wifi connectivity (both simultaneously possible)
  • relative simple configuration (compared to Marlin firmware)

Cons:

  • no Ethernet (Wifi is less reliable)

Software Configuration

Majority of configuration is done via a file-system on a SD card which contains a bunch of .g files which define basic settings of the board and machine it operates:

I operate the board direct with USB and Wifi, not in SBC (Single Board Computer) setup.

  • download firmware, single .bin file from (e.g. firmware-stm32f4-wifi-3.4.1_102.bin) and put it into / (root) folder and rename to firmware.bin – it will vanish once installed on the board
  • download web GUI (e.g. DuetWebControl-SD.zip) and then unzip on the SD card, rename folder name as www/
  • run online configurator to get basic configuration config.g, board.txt and multiple other files (all zipped together)
    • enable Wifi: enter your Wifi Name and Wifi Password
    • you get a single zip file, unzip in the / (root) folder
  • insert SD card into the board, restart board
    • eventually the board will join your Wifi network, scan the network to find out which IP it has, then access the board via web-browser, e.g. http://192.168.1.174/
RepRapFirmware Web-GUI

I operate my 3D printers (3x Ashtar K, 1x Ashtar C, 1x CTC DIY I3 Pro) which use different controller boards all accessed via USB cables and Print3r as main interface (CLI) – having an additional Web-GUI aside allows to operate in parallel beside the USB connectivity.

  • 12864 display with knob to configure on the printer
  • USB connectivity to deliver print job
  • Wifi connectivity to access printer via Web-GUI (simultaneously to USB connectivity)

Hardware Configuration

Important is to put the fuses first, otherwise the board won’t operate, further the stepper driver settings, pluggeable fan MOS, limit switches:

Fuses
Fan MOS Modules
Stepper Driver Settings
Limit Switches

Fly Super8 Pins

I configured the board first using simple USB power delivery, later when the 12V power supply is attached I remove the small jumper to avoid the USB powers the board.

Limit Switches / Endstops

In config.g following lines define the limit switches / endstops:

; Endstops
M574 X1 S1 P"io0"                            ; configure switch-type (e.g. microswitch) endstop for low end on X via pin io0
M574 Y1 S1 P"io1"                            ; configure switch-type (e.g. microswitch) endstop for low end on Y via pin io1
M574 Z1 S1 P"io2"                            ; configure switch-type (e.g. microswitch) endstop for low end on Z via pin io2

therefore the endstops are laid out as such:

Attention: the limit switch with three wires must be inserted correctly, otherwise you short GND with 5V when pushing the switch. The proper layout of io[012] pins (left-to-right):

  • Signal
  • GND
  • 5V
Makerbot Endstop V1.2: Pin 1: Signal, Pin 2&3: GND, Pin 4: 5V

Bed Heating & Hotends

Given the config.g defines the heaters as such:

; Heaters
M308 S0 P"ADC_0" Y"thermistor" T100000 B4092 ; configure sensor 0 as thermistor on pin ADC_0
M950 H0 C"bed" T0                            ; create bed heater output on bed and map it to sensor 0
M307 H0 B0 S1.00                             ; disable bang-bang mode for the bed heater and set PWM limit
M140 H0                                      ; map heated bed to heater 0
M143 H0 S120                                 ; set temperature limit for heater 0 to 120C
M143 H0 S120                                 ; set temperature limit for heater 0 to 120C
M308 S1 P"ADC_1" Y"thermistor" T100000 B4092 ; configure sensor 1 as thermistor on pin ADC_1
M950 H1 C"heat0" T1                          ; create nozzle heater output on heat0 and map it to sensor 1
M307 H1 B0 S1.00                             ; disable bang-bang mode for heater  and set PWM limit
M143 H1 S280                                 ; set temperature limit for heater 1 to 280C

; Fans
M950 F0 C"fan0" Q500                         ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1                               ; set fan 0 value. Thermostatic control is turned off

therefore the connections are:

  • Bed Temperature Sensor ADC0
  • Bed Heater BED_OUT
  • Hotend 1 Temperature Sensor ADC1
  • Hotend 1 Heater HEAT0
  • Part Cooler FAN0

M503 Dump for Ashtar D

M503 dump for Ashtar D (Classic XY) with 400×400 bed, single extruder:

> M503
; Configuration file for Fly Super8 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.4.0-LPC-STM32+4 on Tue Aug 16 2022 20:32:44 GMT+0200 (Central European Summer Time)

; General preferences
G90                                          ; send absolute coordinates...
M83                                          ; ...but relative extruder moves
M550 P"Ashtar D1"                            ; set printer name
;M669 K1                                      ; select CoreXY mode

; Network
M552 S1                                      ; enable network
M586 P0 S1                                   ; enable HTTP
M586 P1 S0                                   ; disable FTP
M586 P2 S0                                   ; disable Telnet

; Drives
M569 P0 S1                                   ; physical drive 0 goes forwards using default driver timings
M569 P1 S1                                   ; physical drive 1 goes forwards using default driver timings
M569 P2 S1                                   ; physical drive 2 goes forwards using default driver timings
M569 P3 S1                                   ; physical drive 3 goes forwards using default driver timings
M569 P4 S1                                   ; physical drive 4 goes forwards using default driver timings
M584 X0 Y1 Z2:3 E4:5                         ; set drive mapping: Z drivers port 3&4, E drives 4&5
M350 X16 Y16 Z16 E16 I1                      ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z3200.00 E420.00            ; set steps per mm
M566 X900.00 Y900.00 Z30.00 E120.00          ; set maximum instantaneous speed changes (mm/min)
M203 X6000.00 Y6000.00 Z150.00 E1200.00      ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z20.00 E250.00          ; set accelerations (mm/s^2)
M906 X800 Y800 Z800 E800 I30                 ; set motor currents (mA) and motor idle factor in per cent
M84 S30                                      ; Set idle timeout

; Axis Limits
M208 X0 Y0 Z0 S1                             ; set axis minima
M208 X380 Y380 Z380 S0                       ; set axis maxima

; Endstops
M574 X1 S1 P"!io0"                            ; configure switch-type (e.g. microswitch) endstop for low end on X via pin io0
M574 Y1 S1 P"!io1"                            ; configure switch-type (e.g. microswitch) endstop for low end on Y via pin io1
M574 Z1 S1 P"!io2"                            ; configure switch-type (e.g. microswitch) endstop for low end on Z via pin io2

; Z-Probe
;M558 P0 H5 F120 T6000                        ; disable Z probe but set dive height, probe speed and travel speed
;M557 X15:215 Y15:195 S20                     ; define mesh grid

; Heaters
M308 S0 P"ADC_0" Y"thermistor" T100000 B4092 ; configure sensor 0 as thermistor on pin ADC_0
M950 H0 C"bed" T0                            ; create bed heater output on bed and map it to sensor 0
M307 H0 B0 S1.00                             ; disable bang-bang mode for the bed heater and set PWM limit
M140 H0                                      ; map heated bed to heater 0
M143 H0 S120                                 ; set temperature limit for heater 0 to 120C
M143 H0 S120                                 ; set temperature limit for heater 0 to 120C
M308 S1 P"ADC_1" Y"thermistor" T100000 B4092 ; configure sensor 1 as thermistor on pin ADC_1
M950 H1 C"heat0" T1                          ; create nozzle heater output on heat0 and map it to sensor 1
M307 H1 B0 S1.00                             ; disable bang-bang mode for heater  and set PWM limit
M143 H1 S280                                 ; set temperature limit for heater 1 to 280C

; Fans
M950 F0 C"fan0" Q500                         ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1                               ; set fan 0 value. Thermostatic control is turned off

; Tools
M563 P0 D0 H1 F0                             ; define tool 0
G10 P0 X0 Y0 Z0                              ; set tool 0 axis offsets
G10 P0 R0 S0                                 ; set initial tool 0 active and standby temperatures to 0C

; Custom settings are not defined

; Miscellaneous
M501                                         ; load saved parameters from non-volatile memory

; 12864 Display                              ; https://teamgloomy.github.io/fly_super8_screen_12864.html
;M950 P1 C"LCD_D4"
;M42 P1 S0
;G4 P500
;M42 P1 S1
;M918 P2 C30 F100000 E4

; M918 P1 E-4 F2000000                        ; https://github.com/jadonmmiller/UltimateDuetMenuSystem

M950 P1 C"LCD_D4"
M42 P1 S0
G4 P500
M42 P1 S1
M918 P2 C30 F100000 E4

Multiple Materials/Colors

With 8 stepper drivers one is able to run:

  • 3x motors for X, Y, Z(2) – attach two Z stepper motors to one driver via splitter
  • 5x extruders (colors or materials), the board supports 4 hotends (4 different temperatures)

Gallery

Board Comparison 2022

As of 2022 (I intend to update this) following boards are suitable for my cases:

MKS Monster8 V1.0/V2.0 & 12864 displayMellow Fly Super8 V1.2 & 12864 displayDuet 3 Mini 5+ & Duet 3 Mini 2+Duet 3 MB 6HC & Duet 3 Expansion 3HC
Price55 EUR80 EUR155 EUR (120+35)385 EUR (255+130)
Stepper Drivers887 (5+2)9 (6+3)
Stepper Connectors9 (dual Z)879
Hotends345 (2+3)6 (3+3)
USBYES (USB-C)YES (USB-C)YES (MicroUSB)YES (MicroUSB)
WIFI– / YES3)YESYES1)YES1)
Ethernet––YES1)YES1)
FirmwareMarlin 2.xMarlin 2.x
RepRapFirmware 3.4.x		RepRapFirmwareRepRapFirmware

Alternatively, there are Duet 2 & 3 clones available on the market:

Duet 2 WIFI CloneDuet 2 WIFI OriginalDuet 3 6HC FYSETC Clone with Duet 3 3HCDuet 3 6HC Original with Duet 3 3HC
Price30-50 EUR2)175-185 EUR1) 225 EUR (150+75)385 EUR (255+130)
Stepper Drivers559 (6+3)9 (6+3)
Stepper Connectors6699
Hotends227 (4+3)6 (3+3)
USBYES (MicroUSB)YES (MicroUSB)YES (MicroUSB)YES (MicroUSB)
WIFIYESYES1)–YES1)
Ethernet–YES1)
YES
YES1)
FirmwareRepRapFirmwareRepRapFirmwareRepRapFirmwareRepRapFirmware
  1. either WIFI or Ethernet
  2. without or with display
  3. MKS Monster8 V2.0 has Wifi module option

As of 2022, RepRapFirmware has become quasi standard in professional level 3D printing; while a lot of people run Klipper & Marlin together I can’t see the point doing this*) but rather have a more capable microcontroller like the Duet boards have to run the printer and manage WIFI / Ethernet at the same time. The only reason to run Klipper on a Single Board Computer (SBC) setup like Raspberry Pi is cost and enhance simple microcontrollers functionality this way.

MarlinKlipper & MarlinRepRapFirmware with Duet
CPUs1x Simple Microntroller1x SBC + 1x Simple Microcontroller1x Capable Microcontroller
ConnectivityUSB onlyUSB, Ethernet and/or WIFIUSB and Ethernet or WIFI
Configuration3x .h files, recompiling requiredsingle .cfg filesingle .g file**)
Boot Time3sKlipper 30s, Marlin 3s3s

*) running different kinematics on the SBC converting G-code on the fly might be a reason
**) multiple .g file can be used optionally

If you are cheap, buy the Duet clones, if you want to support Open Source and Open Hardware community, buy from Duet3d.com direct, pricing is +45% of the clone prices, whereas the Duet resellers add another +15% (Clone: EUR 150, Duet3d.com: 220 EUR, Reseller 255 EUR)

RepRapFirmware: Mind the SD Card

Whether to run an original Duet board or a clone, one thing though one might pay attention to is the SD card, it is the weakest link as far I can tell:

  • SD card needs to be present at all time to provide configuration
  • SD card is not written regularly to unless the logging is enabled

After power-cycling the board, as it was in a strange state no longer responding to G-code properly, the display remained blank, no response to G0/G1 – after investigation it turned out, a single file vanished from the SD card: config.g – the main configuration file, and that is bizarre. The board appeared to be broken, when in truth, the SD card came to its end of life of operating reliably already after only ~1.5 years. The SD card was the one originally shipped with. In this light, a Marlin-based board requiring no SD card being present operates more reliable, unless one uses an industrial grade SD card.

References