This command sets and/or reports the Linear Advance K factors.
Setting the K factor to 0 disables Linear Advance.
With the EXTRA_LIN_ADVANCE_K option Marlin
maintains two slots for each extruder. The first slot is set with K and the second slot is set with L, then select the first using S0 and the second using S1.
for details on how to determine the K factor and a link to our calibration tool.
M900 [K<kfactor>] [L<kfactor>] [S<slot>] [T<index>]
The K factor to set for the specified extruder. Unchanged if omitted. Set this value higher for more flexible filament or a longer filament path.
With EXTRA_LIN_ADVANCE_K this sets the primary
K factor. Note that this factor may be inactive and won’t take effect until the next M900 S0.
Set the second K factor for the specified extruder. Requires EXTRA_LIN_ADVANCE_K. Note that this factor may be inactive and won’t take effect until the next M900 S1.
Select slot and activate the last stored value. Requires EXTRA_LIN_ADVANCE_K.
Extruder to which K, L, and S will apply. Requires EXTRA_LIN_ADVANCE_K.
Fetch the K factor
Set the K factor
Disable Linear Advance
EXTRA_LIN_ADVANCE_K adds an extra storage slot.
M900 S0 ; Select main K factor and apply it
M900 T2 K0.22 L0.4 ; Set both T2 K factors. K0.22 will be applied.
M900 T2 S1 ; Select extra K factor. L0.4 will be applied.
M900 T2 S1 ; (does nothing this time)
M900 T2 L0.3 ; Set T2 extra (and active) K factor
M900 T2 S0 ; Select main K factor (0.22)