docs/machine.UART: Deconditionalize normal methods.

docs/library/machine.UART.rst

@@ -69,15 +69,14 @@ Methods
            When no pins are given, then the default set of TX and RX pins is taken, and hardware 
            flow control will be disabled. If pins=None, no pin assignment will be made.
 
-.. only:: not port_esp8266
-
 .. method:: UART.deinit()
 
    Turn off the UART bus.
 
 .. method:: UART.any()
 
-       Return the number of characters available for reading.
+   Return true value if there're characters available for reading. On some
+   boards, the number of available characters is returned.
 
 .. method:: UART.read([nbytes])
 
@@ -107,13 +106,10 @@ Methods
 
    Return value: number of bytes written or ``None`` on timeout.
 
-.. only:: not port_esp8266
-
 .. method:: UART.sendbreak()
 
    Send a break condition on the bus. This drives the bus low for a duration
-       of 13 bits.
-       Return value: ``None``.
+   longer than required for a normal transmission of a character.
 
 .. only:: port_wipy
 
@@ -140,8 +136,6 @@ Methods
 
        Returns an irq object.
 
-.. only:: not port_esp8266
-
     Constants
     ---------