Short explanation: A parameter in TinyG was found to have default value which might cause a problem in some setups. Answering “Fix” will correct it.

Long explanation: LitePlacer uses the TinyG built-in homing procedure to probe z values; that is, to automatically measure pickup and placement heights. The process works so, that the axis travels towards the switch, detects the switch closure, then backs off until the switch clears. The parameter controls the maximum allowed amount of travel for the switch clearance.

The probing action needs the switch to clear, otherwise things go wrong. It was discovered that the default value was on the low side, causing problems with some users. Therefore, the software now checks this. If a low value is found, you are presented with a dialog showing the current value, and suggesting to set the backoff value to 10mm. If you see this dialog, it is because:

• You updated the TinyG, and the backoff value is in its (default) low value.
• You are using the board with other programs, which have their own opinion on the subject.

For the latter, you have an option to keep the current value and not been bothered again.

Note, that changing the value doesn’t affect the operation: The homing still stops at once when the switch is cleared, it only gives the TinyG more room for the operation to succeed.