TODO

• position callback called on a timer. Motion handlers register with it for each axis

• Convert stepper to use position as mm instead of steps

• Brake outputs for each axis

• spindle speed variation. M138 / M139 https://www.haascnc.com/service/codes-settings.type=mcode.machine=mill.value=M138.html

Haas - 4th axis - M11 unclamp, M10 clamp 5th axis - M13 unclamp, M12 clamp

• Properly calculate feed rate on 3 axis (GRBL is wrong??)
• Calculate 5 axis feed rate using distance to axis of rotation
• Support inverse time feed rate

http://linuxcnc.org/docs/devel/html/motion/5-axis-kinematics.html http://linuxcnc.org/docs/html/gcode/g-code.html#gcode:g93-g94-g95