Linear Advance, is it coming back?  

Re: Linear Advance, is it coming back?

I know this is only semi related to this thread but.....

I'm pretty used to configuring Marlin so can you almost use that current version or do you have to use the files provided on Github?

What github? Both original marlin, and the prusa fork are on github, and both have several branches. Or are you asking about the difference between the firmware available on the prusa site and the files in the prusa fork on github?

Re: Linear Advance, is it coming back?

Marlin currently does not support 32bit chips at all.

Really? Have a look at https://github.com/MarlinFirmware/Marlin/tree/bugfix-2.0.x/Marlin/src/HAL , that has at least three different 32bit chips supported.

Re: Linear Advance, is it coming back?

For better 32-bit support. best to go to the Marlin 2.0 branch:

https://github.com/MarlinFirmware/Marlin/tree/bugfix-2.0.x

Re: Linear Advance, is it coming back?

I mean... http://blog.mmone.de/2017/04/05/howto-build-marlin-3d-printer-firmware-on-the-raspberry-pi/

Re: Linear Advance, is it coming back?

Marlin currently does not support 32bit chips at all.

Really? Have a look at https://github.com/MarlinFirmware/Marlin/tree/bugfix-2.0.x/Marlin/src/HAL , that has at least three different 32bit chips supported.

According to boards.h, I didn't see any boards listed there that include a 32bit chip. I admit that I might have missed something.

Re: Linear Advance, is it coming back?

For better 32-bit support. best to go to the Marlin 2.0 branch:

https://github.com/MarlinFirmware/Marlin/tree/bugfix-2.0.x

Obviously, I hadn't noticed the 2.0 branch 😳 And keon.k is right, there are already 32bit boards/chips supported so let's hope that 32bit i3's will come sooner rather than later.

Re: Linear Advance, is it coming back?

I dont even know why this is up for debate. Obviously the next models will have a 32 bit chip. From what i have seen from Prusa so far they constantly innovate and push the boundaries.

Since the Mk3 is already past its max stable CPU load, thus them having to disable LA. The only option if Prusa wants to continue to innovate and add features is to go 32 bit. Its either that or call it quits with what they have now and from what i have seen thats not the Prusa way.

Re: Linear Advance, is it coming back?

Just my 2 cents but the ignorance in some of these threads is amazing. It's obvious that many people just regurgitate what they want to hear instead of actually trying to understand the reality, cause, and effect of the problem.

Re: Linear Advance, is it coming back?

Just my 2 cents but the ignorance in some of these threads is amazing. It's obvious that many people just regurgitate what they want to hear instead of actually trying to understand the reality, cause, and effect of the problem.

Could you please elaborate?

Re: Linear Advance, is it coming back?

Since the Mk3 is already past its max stable CPU load, thus them having to disable LA.

I'm using the MK2 with Linear Advance for three months now. It works, even the old board can handle it.
The only thing that isn't working reliably with Linear Advance is the serial buffer + streaming commands from Octoprint, which needs a rewrite of a bit of software on the board to make OctoPrint happy again.

But yes, the 8 bit board can't handle anymore than LA and the current ludicrous speed of 200mm/sec infill, something beefier needs to come if there will be any more groundbreaking print related features.

The Duet WiFi is pretty overkill, but all i see this board do except print (and not as well as well as my finely tuned MK2) is drive a big display, some internal webserver, and plugins.
A Raspbnerry Pi can do all of those, too.

Remember, the hardware will only as good as the software that runs on it (quote Steve Jobs), and there are some things they can pull off with the Einsy + Raspberry combo.

At least, the future upgrades will be more future proof now that we have 24V, and the surrounding components for it.

32bit board upgrade? no probs, put a Duet or something else from Prusa in the Future in there.

Re: Linear Advance, is it coming back?

It's been my experience LA works just fine on MK3 as well, as long as you are printing from SD. Curious when this https://github.com/prusa3d/Prusa-Firmware/pull/457 is going to get merged.

Re: Linear Advance, is it coming back?

I know this is only semi related to this thread but.....

I'm pretty used to configuring Marlin so can you almost use that current version or do you have to use the files provided on Github?

What github? Both original marlin, and the prusa fork are on github, and both have several branches. Or are you asking about the difference between the firmware available on

the prusa site and the files in the prusa fork on github?

Yeah I guess what I was trying to say was are they interchangeable, the prusa version looks very stripped down compared to marlin 1.1.8.

Can I comment in/out things in the prusa version the same way I do it in marlin?

I expect it won’t be long until the enisy board is supported in the general marlin unless it already is.

Re: Linear Advance, is it coming back?

Okay boys and girls, here's the firmware with LA enabled, all the latest and greatest commits as of today:

Notable improvements:

Saw somewhere on Github that new official firmware will be out soon, will post it here with LA enabled as soon as it's out.

Re: Linear Advance, is it coming back?

Okay boys and girls, here's the firmware with LA enabled, all the latest and greatest commits as of today:

3.1.1-LA-Enabled-02-20-2018.zip

Notable improvements:

Saw somewhere on Github that new official firmware will be out soon, will post it here with LA enabled as soon as it's out.

Thank you! I will be trying it out in just a sec to see how it goes.

Re: Linear Advance, is it coming back?

Yeah I guess what I was trying to say was are they interchangeable, the prusa version looks very stripped down compared to marlin 1.1.8.

Can I comment in/out things in the prusa version the same way I do it in marlin?

The prusa fork was created quite a while ago, and the codebase has diverged quite a bit since then. There are a lot of changes in the prusa fork that are specifically tuned to the prusa printers. Not just stuff in configuration.h, but over the entire codebase. There are some Gcode flavor changes, they have reworked the bed leveling procedure, they added a lot of calibration stuff.

You can definitely try running original Marlin and see how well it works. I don't think anyone recommends it though. The main hurdle is probably the fact that the MK3 has no physical endstops, it uses the stepper drivers to detect the axis edge instead.

And yes, you can enable/disable options in the prusa fork, the same way you can in original marlin, but you shouldn't have to? The prusa fork has already been optimized. Unless you've made modifications to your printer, of course. 🙂

Re: Linear Advance, is it coming back?

Does Simplify3D activate Linear Advance on the MK3? I print from SD cards only

Re: Linear Advance, is it coming back?

Yeah I guess what I was trying to say was are they interchangeable, the prusa version looks very stripped down compared to marlin 1.1.8.

Can I comment in/out things in the prusa version the same way I do it in marlin?

The prusa fork was created quite a while ago, and the codebase has diverged quite a bit since then. There are a lot of changes in the prusa fork that are specifically tuned to the prusa printers. Not just stuff in configuration.h, but over the entire codebase. There are some Gcode flavor changes, they have reworked the bed leveling procedure, they added a lot of calibration stuff.

You can definitely try running original Marlin and see how well it works. I don't think anyone recommends it though. The main hurdle is probably the fact that the MK3 has no physical endstops, it uses the stepper drivers to detect the axis edge instead.

And yes, you can enable/disable options in the prusa fork, the same way you can in original marlin, but you shouldn't have to? The prusa fork has already been optimized. Unless you've made modifications to your printer, of course. 🙂

Thanks for getting back to me, I don’t think I’ll even try to run marlin on my mk3 when it arrives but it’s good getting the low down from people who have looking into it in more detail.

It’s good to be able to have control of what features you may or may not what to use buy playing with the prusa folk of the firmware, but like you said if theres no mods made it’s should really be needed it’s shouldn’t really be needed

Re: Linear Advance, is it coming back?

Does Simplify3D activate Linear Advance on the MK3? I print from SD cards only

my experience with lin advance on my other printer is its a firmware feature not slicer. you may want to look into setting K value by m900 in your start up code as it will chance for each material. if it works in the same way.

also something else to consider is lin advance doesn't like variable extrusion widths (S3D) and also coast and wipe settings. so i read and found it worked much better with Sli3er. but like i say that with my other printer

Re: Linear Advance, is it coming back?

While the LA feature is a firmware function, you still need to use M codes to use it. For example "M900 K30" for PLA.

"These values are preset in our Slic3r PE. The K value is set in custom gcode section in the Filament Settings tab, NOT under the printer specific custom gcode. PrusaControl uses the same K values but will not allow users editing."

See https://www.prusaprinters.org/fw-3-1-0-linear-advance-drivers-1-9-1/ for more info.

John

Re: Linear Advance, is it coming back?

Oh I will feed you baby birds. 🙂 From the 3.1.2 RC1 firmware thread:

3.1.2 RC1 won't compile with LIN_ADVANCE defined, I am working on getting a pull request in to fix (Edit: https://github.com/prusa3d/Prusa-Firmware/pull/503 ). Looks like they renamed a function and skimmed over changing it in an linear advance defined section:

Old code in ConfigurationStore.cpp, calculate_volumetric_multipliers() no longer exists because it was renamed:
#ifdef LIN_ADVANCE
if (level >= 10) {
EEPROM_READ_VAR(i, extruder_advance_k);
EEPROM_READ_VAR(i, advance_ed_ratio);
}
calculate_volumetric_multipliers();
#endif //LIN_ADVANCE

My change to match up with what they did elsewhere:
#ifdef LIN_ADVANCE
if (level >= 10) {
EEPROM_READ_VAR(i, extruder_advance_k);
EEPROM_READ_VAR(i, advance_ed_ratio);
}
calculate_extruder_multipliers();
#endif //LIN_ADVANCE

After that change it compiles with no issue, and I have it printing a calibration cube now without problems. Make sure you do self test again, as it does have a "calibrating home" step where it bumps X and Y limits several times to determine this. Please find my unofficial LA enabled firmware below: