grblHAL Alarm 22

grblHALAlarmNot a position problem

A buffer in the controller overflowed.

Not a position problem. Hamrun's reading: if the job stopped mid-cut, home before trusting position. (Hamrun's reading)
What to do
  1. Reset the controller.
  2. If it happens while streaming, try a different sender or a slower connection.
Official grblHAL message: “Buffer overflow.” source

Got a different message?

Paste it into the decoder. Hamrun's editor checks your G-code before you run it, so a toolpath that leaves the machine's travel or a missing feed rate is caught before the machine stops.

Official text copied from the grblHAL source on 2026-11-01. Steps and the position answer are Hamrun's reading unless marked “firmware says”. User reports are labelled CLAIMED.