IndexOnlyHoming

The new homing method "Index only" does not require home switches. It is now in head/trunk and will be part of the EMC2 v2.2 release.

This method requires the operator to manually jog the machine axis to line up witness lines for each axis prior to executing the home command. Once homing is started the machine will move in the direction defined until the first index pulse is detected. Total motion to home is less than 1 full revolution of the encoder. If a home offset is defined machine will then rapid to Home.

Pros:

• Does not require an extra set of home switches, which reduces I/O needs.
  

Cons:

• Current config only works for encoders with index channel.
• Requires operator to manually pre-align machine before home.
• When the encoder is mounted on a servo which has a belt/gear reduction to the lead screw the actual machine movement might be very small. In this case, pre-alignment with witness lines must be done precisely.