diff --git a/.gitignore b/.gitignore
index ea416fae48..d3eb71b6c1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -40,3 +40,4 @@ nsh_romfsimg.h
 cscope.out
 .configX-e
 nuttx-export.zip
+.~lock.*
diff --git a/Documentation/rc_mode_switch.odg b/Documentation/rc_mode_switch.odg
new file mode 100644
index 0000000000..77194369b4
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diff --git a/Documentation/rc_mode_switch.pdf b/Documentation/rc_mode_switch.pdf
new file mode 100644
index 0000000000..bcdc422490
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