PRIME MOTIONFirmware settings
Your controller stores its own configuration: steps per millimetre, maximum rates, acceleration, travel, homing behaviour, spindle range. In Grbl these are the numbered $ settings, such as $110 for the X axis maximum rate. They live in the controller, not in the app, and they decide how the machine physically moves.
Prime Motion shows them in Settings → Firmware. The field-by-field reference is Settings → Firmware; this page explains what you are looking at.
Where the values come from
The line under the firmware name says how fresh the table is:
| Line | Meaning |
|---|---|
| Live from controller | Read from the connected controller in this session |
| Last read from machine — connect for live values | The values seen the last time this machine was connected |
| Catalog seed for machine — never read from the controller | The model's published defaults; this controller has never been read |
Trust Live from controller. The other two are references, not measurements of your machine.
Changing a setting
On a live connection to a Grbl 1.1 or grblHAL controller, tap a value, type the new one and tap SET, or ✕ to cancel.
Prime Motion sends the setting and reads it back. The banner above the table then says either $N=value verified by read-back, or why it failed: below the controller's minimum, above its maximum, the controller reporting a different value from the one sent, or the controller's own error.
You cannot write while a job is running (A job is running — firmware writes are locked out), without a connection, or to a FluidNC controller, whose settings live in its configuration file.
When the profile and the controller disagree
Prime Motion compares what your machine profile expects with what the controller reports. Where they differ in a way that matters, a card above the table explains it, such as a profile expecting homing switches while the controller has homing turned off ($22=0). Each card shows both sides and offers the fix on either side. See Supported controllers.
Settings the app writes elsewhere
A few settings are better changed where their meaning is clear:
- Probe input inverted ($6) — in Settings → Connection → Touch Plate, beside the plate it belongs to.
- Send Machine Configuration — the setup wizard's Configure step writes a Carbide 3D machine's complete factory set.