Originally shared by James Kasper - CBWP
how many of you are familiar with the ultimaker?
I have been comparing the schematics to the ramps 1.4 and there are a lot of pull up resistors not used in the ultimaker. Are they using the internal pull ups of the mega? enable pins on the Pololus, the limit switches…
They use the same mosfets for the heaters but on the ramp1.4 schematic, there is a 10r resistor inline between the digital pin and the gate. is that to absorb a surge? what is 10r? misprint on the schematic? it wasn’t there on accident. On the ultimaker schematic there are pull up resistors for the 3 multi-stepping jumper selections they are not on the ramps… the value on the print is 4k7 Is that supposed to be 4.7k?
Is the software defaulted for internal pull up resistors? (Marlin) or is there a config setting for it?