doc: document MENU RESOLUTION

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/doc/menu.txt b/doc/menu.txt
index 97e172f..e160124 100644 (file)
--- a/doc/menu.txt
+++ b/doc/menu.txt
@@ -203,12 +203,24 @@ MENU MASTER PASSWD passwd
        work.
 
 
+MENU RESOLUTION height width
+
+       Requests a specific screen resolution when in graphics mode.
+       The default is "640 480" corresponding to a resolution of
+       640x480 pixels, which all VGA-compatible monitors should be
+       able to display.
+
+       If the selected resolution is unavailable, the text mode menu
+       is displayed instead.
+
+
 MENU BACKGROUND background
 
        For vesamenu.c32, sets the background image.  The background
        can either be a color (see MENU COLOR) or the name of an image
-       file, which should be 640x480 pixels and either in PNG or JPEG
-       format.
+       file, which should be the size of the screen (normally 640x480
+       pixels, but see MENU RESOLUTION) and either in PNG, JPEG or
+       LSS16 format.
 
 
 MENU BEGIN [tagname]