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diff --git a/docs/library/machine.SPI.rst b/docs/library/machine.SPI.rst deleted file mode 100644 index 080f6fdfb..000000000 --- a/docs/library/machine.SPI.rst +++ /dev/null @@ -1,97 +0,0 @@ -.. currentmodule:: machine -.. _machine.SPI: - -class SPI -- a Serial Peripheral Interface bus protocol (master side) -===================================================================== - -SPI is a synchronous serial protocol that is driven by a master. At the -physical level, a bus consists of 3 lines: SCK, MOSI, MISO. Multiple devices -can share the same bus. Each device should have a separate, 4th signal, -SS (Slave Select), to select a particular device on a bus with which -communication takes place. Management of an SS signal should happen in -user code (via machine.Pin class). - -Constructors ------------- - -.. class:: SPI(id, ...) - - Construct an SPI object on the given bus, ``id``. Values of ``id`` depend - on a particular port and its hardware. Values 0, 1, etc. are commonly used - to select hardware SPI block #0, #1, etc. Value -1 can be used for - bitbanging (software) implementation of SPI (if supported by a port). - - With no additional parameters, the SPI object is created but not - 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. - -Methods -------- - -.. method:: SPI.init(baudrate=1000000, \*, polarity=0, phase=0, bits=8, firstbit=SPI.MSB, sck=None, mosi=None, miso=None, pins=(SCK, MOSI, MISO)) - - Initialise the SPI bus with the given parameters: - - - ``baudrate`` is the SCK clock rate. - - ``polarity`` can be 0 or 1, and is the level the idle clock line sits at. - - ``phase`` can be 0 or 1 to sample data on the first or second clock edge - respectively. - - ``bits`` is the width in bits of each transfer. Only 8 is guaranteed to be supported by all hardware. - - ``firstbit`` can be ``SPI.MSB`` or ``SPI.LSB``. - - ``sck``, ``mosi``, ``miso`` are pins (machine.Pin) objects to use for bus signals. For most - hardware SPI blocks (as selected by ``id`` parameter to the constructor), pins are fixed - and cannot be changed. In some cases, hardware blocks allow 2-3 alternative pin sets for - a hardware SPI block. Arbitrary pin assignments are possible only for a bitbanging SPI driver - (``id`` = -1). - - ``pins`` - WiPy port doesn't ``sck``, ``mosi``, ``miso`` arguments, and instead allows to - specify them as a tuple of ``pins`` parameter. - -.. method:: SPI.deinit() - - Turn off the SPI bus. - -.. method:: SPI.read(nbytes, write=0x00) - - Read a number of bytes specified by ``nbytes`` while continuously writing - the single byte given by ``write``. - Returns a ``bytes`` object with the data that was read. - -.. method:: SPI.readinto(buf, write=0x00) - - Read into the buffer specified by ``buf`` while continuously writing the - single byte given by ``write``. - Returns ``None``. - - Note: on WiPy this function returns the number of bytes read. - -.. method:: SPI.write(buf) - - Write the bytes contained in ``buf``. - Returns ``None``. - - Note: on WiPy this function returns the number of bytes written. - -.. method:: SPI.write_readinto(write_buf, read_buf) - - Write the bytes from ``write_buf`` while reading into ``read_buf``. The - buffers can be the same or different, but both buffers must have the - same length. - Returns ``None``. - - Note: on WiPy this function returns the number of bytes written. - -Constants ---------- - -.. data:: SPI.MASTER - - for initialising the SPI bus to master; this is only used for the WiPy - -.. data:: SPI.MSB - - set the first bit to be the most significant bit - -.. data:: SPI.LSB - - set the first bit to be the least significant bit |