diff --git a/Documentation/GCodes.md b/Documentation/GCodes.md
index f7813830d..e7b21b760 100644
--- a/Documentation/GCodes.md
+++ b/Documentation/GCodes.md
@@ -126,6 +126,8 @@ M362 - SCARA calibration: Move to cal-position PsiA (0 deg calibration)
 M363 - SCARA calibration: Move to cal-position PsiB (90 deg calibration - steps per degree)
 M364 - SCARA calibration: Move to cal-position PSIC (90 deg to Theta calibration position)
 M365 - SCARA calibration: Scaling factor, X, Y, Z axis
+M928 - Start SD logging (M928 filename.g) - ended by M29
+M999 - Restart after being stopped by error
 ```
 
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