Configuring RepRapFirmware for a CoreXY printer
Configuration of the dc42 fork of RepRapFirmware for a CoreXY printer is very similar to configuration for a Cartesian printer, which is described at Configuring RepRapFirmware for a Cartesian printer. Only the differences will be described here.
Main configuration file
To switch the firmware to CoreXY mode, add this command to the movement section:
M667 S1 ; switch to CoreXY mode
If any motors move the wrong way, you can use M569 commands to alter the directions.
The method of setting up simultaneous homing is different for CoreXY printers. On a Cartesian printer, if you use the G1 command with S1 parameter to perform a homing move on several axes simultaneously, each axis will continue moving until either the specified movement amount has been completed or the homing switch for that axis has been triggered. On a CoreXY printer, the whole move will be terminated when the first homing switch is triggered. Therefore, to do simultaneous XY homing, your homeall.g file needs to first home X and Y together, then home them separately. For example, if your printer has homing switches at the low ends of the X and Y axes, use this pattern:
G91 G1 S1 X-240 Y-240 F3000 ; course home X or Y G1 S1 X-240 ; course home X G1 S1 Y-240 ; course home Y G1 X4 Y4 F600 ; move away from the endstops G1 S1 X-10 ; fine home X G1 S1 Y-10 ; fine home Y ; Z homing section follows ...