docs: miniterm suspend function

Author: zsquareplusc

documentation/tools.rst

@@ -274,6 +274,10 @@ Typing :kbd:`Ctrl+T Ctrl+H` when it is running shows the help text::
     ---    x X        disable/enable software flow control
     ---    r R        disable/enable hardware flow control
 
+:kbd:`Ctrl+T s` suspends the connection (port is opened) and reconnected when a
+key is pressed. This can be used to temporarily access the serial port with an
+other application, without exiting miniterm.
+
 .. versionchanged:: 2.5
     Added :kbd:`Ctrl+T` menu and added support for opening URLs.
 .. versionchanged:: 2.6