Firmware flavor MarlinHOH

Hallo all,

just right to the next crazy days I have release a new firmware flavour: MarlinHOH.
This firmware is a spin-off from the original Vellemann V1.4 software, where several errors and a lot of inconsistencies were removed. Some input from the progressing Marlin firmware was taken. But since the progress here is mainly to support more and more devices, my firmware takes the other way: take the most power out of the given board.

The basic part of the Marlin code is written as if it must run on an arduino Uno too. So lot of the capabilities of the harware are waisted with the given firmware. There was may tasks:

  • All time critical tasks are fully (!) interrupt driven.
  • The language can be selected by the LCD menu
  • The handling of two extruders must be much easier.

This is achieved for the latest version V0.7. You can download and test it [here].(
There you will find a closed description about the capabilites and a guideline for installing.

Wish you happy printing.

1 Like

Hi, wanted to try the software.
Unfortunately I have the error “Err. MAXTEMP” in the last LCD line.
I have 2 nozzles and no heating bed.
Maybe you have a tip.

Dear Lutz,

the default configuration is with two nozzles and no heat bed. So in principle it should work without modifications.

MAXTEMP is mostly an indicator for a shortage in the temperature sensor line, so you may check if the both temperature readings are correct (at room temperature).

If this correct please do a manual reset and check the situation again.

You may remove the USB cable and switch on the printer again.

At the moment I have no other ideas to check what is happening.

Please send me your feedback. If you use a controller software like octoprint please send me the log for the ramp-up for further analysis too.

Sorry for this inconvenience, this happened not for my printer. However, it is no longer a “standard” printer. The normal operating condition for the arduino core is about 4.3V due to two silicon diodes in the supply lines: D5 (from 5V regulator) and D6 (from USB interface). According to the datasheet from Atmel the minimum operating voltage must be 4.5V(!). I had some silly effects in the past, which are completely gone since I replaced the two silicon diodes with two Schottky diodes: operating voltage: 4.7V.
It would be a pity if this difference would cause your effect.

Thank you for your prompt reply
With the original Sottware I have no mistakes.
I’ll take a look at the diodes.
I attached a picture of the VertexRepetier.
Maybe they can recognize something.
Greeting Lutz

Dear Lutz,

thank you for your reply. There is an error in the software: the error handling for the heat bed is not fully suppressed even if there is no heatbed installed. I will update the firmware within the next hours and will notify the update.

I did a check of this firmware with my own printer, but with the heat bed temp sensor attached…

Dear Lutz,

the firmware is updated (V0.7a) and available for download. Now it should run as expected.

Sorry for this inconvenience, next time I will do it better…

Happy printing.

Thank you for your prompt reply. I just added the software. There are no more mistakes. I still have the original Noozle. The first test print (without optimization) looks better than the V1.4H2.
Thank you.
Greeting Lutz