Mini Gerbil debugging – homing operation

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Symptom DetailLikely causes and their solutions (in recommended sequence)
Moves in incorrect direction for homingLightburn (or other software) home position incorrectly set.

User has non-standard home position.  For inexperienced user, very strongly recommend using standard home position, see
$3 dir setting

Mini Gerbil settings corrupted – see Mini Gerbil settings
Ignoring limit switches and laser head is grinding into side or cornerLimit switches or their connections may be faulty.  Observe LED 9 – Yellow – Y axis limit and LED 10 – Yellow – X axis limit. Each LED should turn off when the limit switch is engaged.)

If using J5 (non-ribbon connector), check plug is not reversed.  See installation information.

Limit switches mis-wired.  Review installation information.
Makes grinding sound while moving to home. Movement on one or more axes unsuccessful when moving to the home directionCheck for mechanical issues such as incorrect belt tension or obstructions

Ensure Mini Gerbil is using the defalt $ settings listed in

Stepsticks require adjustment. See
Homing position offset from desired positionRecent use of the software has set an offset that needs to be reset.  Type $RST=# in the console.  See
Homing operation is generally correct, but position is of homing is variable along the axis (depending on where the laser head was before starting homing) and not actually in the corner.  You’ve got limit switches connected via the J5 connector.The limit switch plug in the J5 socket is the wrong way around, remove, rotate 180’ and re-insert. Note J5 is polarity defined via connector slots. Only fits in one way.  

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