My printer uses 400mm T8 Tr8x2 Lead Screws for the z axis (one start thread). This should be configured to 1600 steps for the z axis. This was the way the printer was configured before I replaced the TH3D EzBoard (now dead) with the BTT SKR Mini v2.0 board. With the BTT board, when I move the z axis by 10mm, it actually does 20mm when steps are set to 1600. If I change the steps to 800, then the movement is accurate. I replaced the board with my original Creality board, and 1600 steps should be the correct configuration.
Does anyone have any ideas why one board would use 1600 while the BTT uses 800, for lead screws that should be for 1600 steps? Running out of ideas for what to look for.