# StoneFlower3D - how to pause a print?

I've been trying to make a paste extruder and I came across StoneFlower3D. In their site, they mentioned about a feature called Infinite Printing. Please see page number 25 of this document.

They're only using Step, Dir, Enable and GND from main controller and there's not a serial connection with the controller.

Anyone have idea about how they're doing it?

• Moving off-topic - back with a regular printer, you can insert PAUSE commands into a gcode file if you expect to run out of filament, or want to change color, etc. It helps to be on-site to make the change quickly :-) – Carl Witthoft Jun 13 '18 at 13:14
• I read about that in Marlin git hub page. But I was wondering how they are doing it over StoneFlower3d without any command or communication with Main controller – Athul Jun 13 '18 at 17:21
• @Athul The ceramic extruder is taking the signals before the a4988 to make a kind of bridge, so the white module has a new a4988 with a pulse generator to drive as standalone the A4988 so this way the extruder can be cleaned without need of using the 3Dprinter driver; however this doesn't mean that can be paused the whole printer. :) This gave me the idea to extrude cement and adapt the cleaning process. – Fernando Baltazar Jun 16 '18 at 18:15
• @FernandoBaltazar That means,there's a pulse generator inside this white control box. Which can give square pulses to the STEP pin of whatever driver the box contains. So when switch is toggled to KIT position, driver receives pulse from this generator and when in PRINTER position, receives signals from printer controller, Right??? – Athul Jun 17 '18 at 14:26
• @Athul yes, thats right – Fernando Baltazar Jun 18 '18 at 5:06

The extruder is connected to 3d printer mainboard as a stepper driver. That said it is not using standard stepper motor output, but it is fed directly from CPU digital pins.

The extruder has theability to self-feed (load filament) - so that is the reason of kit/printer switches - see pic 1. Then pausing a print to feed the clay tank need to be executed from printer (pause print) and then operated locally in the kit` mode.