diff options
Diffstat (limited to 'docs/library')
| -rw-r--r-- | docs/library/pyb.UART.rst | 38 |
1 files changed, 25 insertions, 13 deletions
diff --git a/docs/library/pyb.UART.rst b/docs/library/pyb.UART.rst index c96810b639..f9760734bc 100644 --- a/docs/library/pyb.UART.rst +++ b/docs/library/pyb.UART.rst @@ -13,7 +13,10 @@ UART objects can be created and initialised using:: uart = UART(1, 9600) # init with given baudrate uart.init(9600, bits=8, parity=None, stop=1) # init with given parameters -Bits can be 8 or 9. Parity can be None, 0 (even) or 1 (odd). Stop can be 1 or 2. +Bits can be 7, 8 or 9. Parity can be None, 0 (even) or 1 (odd). Stop can be 1 or 2. + +*Note:* with parity=None, only 8 and 9 bits are supported. With parity enabled, +only 7 and 8 bits are supported. A UART object acts like a stream object and reading and writing is done using the standard stream methods:: @@ -44,9 +47,9 @@ Constructors initialised (it has the settings from the last initialisation of the bus, if any). If extra arguments are given, the bus is initialised. See ``init`` for parameters of initialisation. - + The physical pins of the UART busses are: - + - ``UART(4)`` is on ``XA``: ``(TX, RX) = (X1, X2) = (PA0, PA1)`` - ``UART(1)`` is on ``XB``: ``(TX, RX) = (X9, X10) = (PB6, PB7)`` - ``UART(6)`` is on ``YA``: ``(TX, RX) = (Y1, Y2) = (PC6, PC7)`` @@ -57,35 +60,44 @@ Constructors Methods ------- -.. method:: uart.any() - - Return ``True`` if any characters waiting, else ``False``. - -.. method:: uart.deinit() - - Turn off the UART bus. - .. method:: uart.init(baudrate, bits=8, parity=None, stop=1, \*, timeout=1000, timeout_char=0, read_buf_len=64) Initialise the UART bus with the given parameters: - + - ``baudrate`` is the clock rate. - - ``bits`` is the number of bits per byte, 8 or 9. + - ``bits`` is the number of bits per character, 7, 8 or 9. - ``parity`` is the parity, ``None``, 0 (even) or 1 (odd). - ``stop`` is the number of stop bits, 1 or 2. - ``timeout`` is the timeout in milliseconds to wait for the first character. - ``timeout_char`` is the timeout in milliseconds to wait between characters. - ``read_buf_len`` is the character length of the read buffer (0 to disable). + *Note:* with parity=None, only 8 and 9 bits are supported. With parity enabled, + only 7 and 8 bits are supported. + +.. method:: uart.deinit() + + Turn off the UART bus. + +.. method:: uart.any() + + Return ``True`` if any characters waiting, else ``False``. + .. method:: uart.read([nbytes]) + Read characters. If ``nbytes`` is specified then read at most that many bytes. + + *Note:* for 9 bit characters each character takes 2 bytes, ``nbytes`` must be even, + and the number of characters is ``nbytes/2``. .. method:: uart.readall() + Read as much data as possible. .. method:: uart.readchar() Receive a single character on the bus. + Return value: The character read, as an integer. Returns -1 on timeout. .. method:: uart.readinto(buf[, nbytes]) |