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#9085 |

Maybe I can shed some light into this…
The way the code is generated is quite intense, but there is no way to avoid massive Gcode files if you want good quality 8bit engravings.
Then there is the way the controller/firmware works.
Usually they try to “look ahead” to get some movements stored for smooth operation.
This sadly fails in standard configurations as we simply have too many lines of code that constantly change.
The main issue however is speed – not the speed of motors but the speed of your connection.
Keep in mind that the next command needs to be available for processing before the current move is over.
It is not like cutting a 100mm line with fixed settings and a fixed speed – in these 100mm you can have more than 100 single commands…
When it comes to Arduino’s or similar processors you need to consider the serial com chip and the CPU speed as well.
57600baud is about the max the Mega can handle before something get’s dropped or mangled up.
A reliable speed on my machine for 0.10 resolution is 850mm/min – anything above and the machine runs into troubles.
Can do 2400mm/min if I really want to but than there is banging, pinholes and so on.
Still working on utilising the bigger memory of the Mega to store commands and serial communication.

Edit: Increasing the buffer to 256 fixes some of the issues and the movement is smoother but still not perfect.
From the SD it works a tiny bit better and filesize is no issue either, unlike with Pronterface always complaining.
Not sure when I find some time to dissect Marlin again and if I can make some changes to the look ahead buffer there….

  • This reply was modified 7 months, 2 weeks ago by Profile photo of Noname007 Noname007.