Resurrection

I have been out of the tech for 5-6 years and have just unearthed my 2013 Mendel 90. As I am reconnecting it I need to get software, and perhaps hardware to make it work again. I am running Ubuntu 22.04 but installs of Printrun / Pronterface crash on launch, Slic3r fails to install and I suspect the world of SW and HW has moved considerably from where I saw it 6 years ago.

Advice /opinions as to:
1. Reverting to an older version of Ubuntu on an old laptop.
2. Adding a local screen and controller to the printer .....
3. Update the printer with a newer control board than the Melzi/Marlin [OEM]

would be welcome !

Progress .... sort of.

As I try to refresh the software toolchain I now have Pronterface running under Ubuntu 22.04 ! Python issues !

Connection to printer is the issue now. I have permissions set properly and the on board UART is reporting. It will not connect regardless of baud rate. I suspect I need to reprogam the board.
I've installed the Arduino IDE but can't find the 'Melzi W/ AT mega1284p ' board in the libraries, or actually find the libraries to download. When trying to upload to the board it times out. It seems I am missing something {or a lot of things}.

Again any suggestions are welcome

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Bill

Very unlikely you would need to reprogram the board as the firmware stored in flash doesn't get forgotten in my experience.

The recent version of Marlin I put on Github comes with support for Melzi with 1284p. I compiled it with Visual Studio Code using the Auto Build Marlin extension as that is the recommended way of doing it nowadays but it says it can still be compiled with Arduino. I didn't need to install any libraries.

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[www.hydraraptor.blogspot.com]

It is a replacement board as the original was physically damaged by parties unknown when I moved to the Great White North.
I have now managed to get a boot loader installed. Currently trying to compile the updated marlin with a borrowed Windows machine. Maybe I should look at the visual code method, but I am not a programmer nor familiar with VSC. Will need to search out how that is done !

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Bill

I think I followed a YouTube video of one of the famous 3D printer vloggers. Perhaps Thomas Sanladerer or Teaching Tech.

IIRC it was just a matter of downloading VSC, installing some plugins and then using the Marlin autobuild.

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[www.hydraraptor.blogspot.com]

I've been looking at some help videos on it from TH3D and will get there. I just got a reply to another query for the Sanguino support lib in Arduino. I now have complilation AND connection !!!

Which brings me to this problem to solve !

Connecting...
start
Printer is now online.
Marlin 2.0.9.3
echo: Last Updated: 2021-12-25 | Author: nophead
echo: Compiled: Jan 12 2023
echo: Free Memory: 12530 PlannerBufferBytes: 1152
echo:EEPROM version mismatch (EEPROM=? Marlin=V86)
echo:Hardcoded Default Settings Loaded
Error:MAXTEMP triggered, system stopped! Heater_ID: E0
Error:MAXTEMP triggered, system stopped! Heater_ID: E0

echo:Err: MAXTEMP
Errorrinter halted. kill() called!
Errorrinter halted. kill() called!

//action:poweroff

I'll now chase a possible thermistor, wiring or config problem ...... but at least I'm closer than Monday !

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Bill

"Error:MAXTEMP" can be caused by several things

Firstly what do you have the set as the hotend thermistor?
keyword TEMP_SENSOR_0

I believe these old machine used a type 1..

What did you set for MOTHEBOARD ?
I believe those old machines have a BOARD_MELZI

Also unplug the hotend thermistor, does the max temp error change ?

check resistance across the hotend thermistor cable pins while unplugged, it should read around 100k in a 25C room.
A shorted thermistor will give a Error:MAXTEMP

Edited 2 time(s). Last edit at 01/13/2023 01:02AM by Dust.

I now have fewer things to check .....
Changed the thermistor in the E3D V6 Hotend as it seemed intermittent.
Recompiled and uploaded with "TEMP_SENSOR_0 5" as I believe that is the correct one as per E3D.
Double checked continuity to the board from terminals on on the Hotend assembly.
Using a hot air gun verified resistance change.

Still get the same error ! Beginning to suspect these lines are reporting something .....

echo:EEPROM version mismatch (EEPROM=? Marlin=V86)
echo:Hardcoded Default Settings Loaded

I am going to try another board to see if the eeprom error follows ....

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Bill

Success !!!!!

Connecting...
start
Printer is now online.
Marlin 2.0.9.3
echo: Last Updated: 2021-12-25 | Author: nophead
echo: Compiled: Jan 13 2023
echo: Free Memory: 12530 PlannerBufferBytes: 1152
echo:EEPROM version mismatch (EEPROM=? Marlin=V86)
echo:Hardcoded Default Settings Loaded
echo:No SD card

Getting closer now Innis & Gunn - here I come !

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Bill

I think to get rid of the EEPROM error you just need to initialise it with M502 followed by M500.

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[www.hydraraptor.blogspot.com]

My celebration was premature ....

echo:V86 stored settings retrieved (620 bytes; crc 4513)
echo:No SD card
Setting hotend temperature to 185 degrees Celsius.
Error:Heating failed, system stopped! Heater_ID: E0
Error:Heating failed, system stopped! Heater_ID: E0

The board swap fixed the immediate fail on startup but it now fails soon after I start heating the hotend. Verified that the thermistor value at the board connection was dropping as it heated up but Pronterface and the board did not report it.


I'm about to order a new Melzi board just to rule a board fault out. Curiously though newer 32bit boards are cheaper ..... worth switching ?

Edited 1 time(s). Last edit at 01/14/2023 04:01PM by Bill_of_the_North.

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Bill

Yes I wouldn't buy a Melzi today but it is probably something else wrong.

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[www.hydraraptor.blogspot.com]

I've run out of ideas to try at this point so I'm looking for a Smoothie board. I like that it is flexible in application to tasks other than 3D printing.

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Bill

Does it display the correct room temperature when cold? If not what does it display?

Since the E3D has more thermal mass than a J-Head perhaps the thermal runaway protection is a false alarm due it not heating as fast as expected. I don't use it most of my machines because it is a PIA. I prefer to live dangerously.

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[www.hydraraptor.blogspot.com]

I was using the E3D before without problem. The heat block did get hot VERY quickly and the thermistor value at the board input showed that.

After a lot of reading, searching and shopping I've ordered a BigTreeTech Manta 8P with the companion CM1 RPi equivalent. According to Teaching tech it is closer to a Pi 3. The board ticks a lot of boxes in that it will run Marlin or Klipper, can also run octo print. Ethernet and other stuff is there too. Wiring looks a little easier than the Melzi board. On Amazon it was cheaper and faster delivery than a Melzi. The Smoothie options are not in stock anywhere ...

Whilst I await delivery I will try the VSCode autoBuild and learn something new !

Thanks for your thoughts and time.

Edited 1 time(s). Last edit at 01/15/2023 05:04PM by Bill_of_the_North.

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Bill

Addendum(b):

Measuring across the the input terminals for temp sense on all 3 boards confirms my suspicions. 2 boards have low resistance on the E-Temp compared to Bed temp. The 3rd board has unrepairable phsical damage yet temperature inputs are the same as the working Bed temp inputs of the other 2.

Thank you all for your time and thoughts. I'll be back with questions when I get the new boards setup !

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Bill

Odd. Do they have different pullup resistors fitted? They should both be 4K7.

A very low value could indicate the thermistor has been shorted to the heater as that blows up the input pin of the MCU.

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[www.hydraraptor.blogspot.com]

At this point I just have to accept that they don't work anymore. The adventure will continue when the BTT Manta 8P with CM1 arrives and I start to learn about Klipper, Octoprint and all the newer environs. As the Pi 4 when available is expensive compared to the CM1 Pi 3 equivalent, and BTT seems to have fostered a growing community around their products how bad can it go ?

It's winter here with -20C some nights so I have time to spare.

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Bill

It is worth checking there isn't a short between the heater and the thermistor as that will destroy most boards.

We live in Tenerife in the winter, so +23C ATM. -1C in the UK.

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[www.hydraraptor.blogspot.com]

BTT Manta 8P with CB1 has arrived and rewiring of the machine has started ! Original wiring was to screw terminals and the new electronics use JST or Dupont pin style ! I'm also converting it to 24 volt and Klipper. Lots of online youtube for these boards but none about fitting to older printers. Sample config files are usually for and Ender, Voron or Creality so it is a challenge !

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Bill