docs: Add documentation for BED_MESH_OFFSET

Signed-off-by:  Eric Callahan <arksine.code@gmail.com>

2 files changed, 15 insertions, 0 deletions

diff --git a/docs/Bed_Mesh.md b/docs/Bed_Mesh.md
index a36f9244..bdc1aa6c 100644
--- a/docs/Bed_Mesh.md
+++ b/docs/Bed_Mesh.md
@@ -430,3 +430,14 @@ probing the "Probe" points will refer to both the tool and nozzle locations.
 `BED_MESH_CLEAR`
 
 This gcode may be used to clear the internal mesh state.
+
+### Apply X/Y offsets
+
+`BED_MESH_OFFSET [X=<value>] [Y=<value>]`
+
+This is useful for printers with multiple independent extruders, as an offset
+is necessary to produce correct Z adjustment after a tool change.  Offsets
+should be specified relative to the primary extruder.  That is, a positive
+X offset should be specified if the secondary extruder is mounted to the
+right of the primary extruder, and a positive Y offset should be specified
+if the secondary extruder is mounted "behind" the primary extruder.
diff --git a/docs/G-Codes.md b/docs/G-Codes.md
index a885aef1..2db1f491 100644
--- a/docs/G-Codes.md
+++ b/docs/G-Codes.md
@@ -433,6 +433,10 @@ The following commands are available when the
   supplied name from persistent memory.  Note that after SAVE or
   REMOVE operations have been run the SAVE_CONFIG gcode must be run
   to make the changes to peristent memory permanent.
+- `BED_MESH_OFFSET [X=<value>] [Y=<value>]`:  Applies X and/or Y
+  offsets to the mesh lookup.  This is useful for printers with
+  independent extruders, as an offset is necessary to produce
+  correct Z adjustment after a tool change.
 
 ## Bed Screws Helper