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Diffstat (limited to 'docs')
| -rw-r--r-- | docs/library/pyb.CAN.rst | 72 |
1 files changed, 53 insertions, 19 deletions
diff --git a/docs/library/pyb.CAN.rst b/docs/library/pyb.CAN.rst index e160f6797..8f417f735 100644 --- a/docs/library/pyb.CAN.rst +++ b/docs/library/pyb.CAN.rst @@ -26,30 +26,30 @@ 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 CAN busses are: - + - ``CAN(1)`` is on ``YA``: ``(RX, TX) = (Y3, Y4) = (PB8, PB9)`` - ``CAN(2)`` is on ``YB``: ``(RX, TX) = (Y5, Y6) = (PB12, PB13)`` Class Methods ------------- .. method:: CAN.initfilterbanks(nr) - + Reset and disable all filter banks and assign how many banks should be available for CAN(1). - + STM32F405 has 28 filter banks that are shared between the two available CAN bus controllers. - This function configures how many filter banks should be assigned to each. ``nr`` is the number of banks - that will be assigned to CAN(1), the rest of the 28 are assigned to CAN(2). + This function configures how many filter banks should be assigned to each. ``nr`` is the number of banks + that will be assigned to CAN(1), the rest of the 28 are assigned to CAN(2). At boot, 14 banks are assigned to each controller. - + Methods ------- .. method:: can.init(mode, extframe=False, prescaler=100, \*, sjw=1, bs1=6, bs2=8) Initialise the CAN bus with the given parameters: - + - ``mode`` is one of: NORMAL, LOOPBACK, SILENT, SILENT_LOOPBACK - if ``extframe`` is True then the bus uses extended identifiers in the frames (29 bits); otherwise it uses standard 11 bit identifiers @@ -83,14 +83,14 @@ Methods Turn off the CAN bus. .. method:: can.setfilter(bank, mode, fifo, params) - + Configure a filter bank: - + - ``bank`` is the filter bank that is to be configured. - ``mode`` is the mode the filter should operate in. - - ``fifo`` is which fifo (0 or 1) a message should be stored in, if it is accepted by this filter. + - ``fifo`` is which fifo (0 or 1) a message should be stored in, if it is accepted by this filter. - ``params`` is an array of values the defines the filter. The contents of the array depends on the ``mode`` argument. - + +-----------+---------------------------------------------------------+ |``mode`` |contents of parameter array | +===========+=========================================================+ @@ -106,11 +106,11 @@ Methods +-----------+---------------------------------------------------------+ |CAN.MASK32 |As with CAN.MASK16 but with only one 32 bit id/mask pair.| +-----------+---------------------------------------------------------+ - + .. method:: can.clearfilter(bank) Clear and disables a filter bank: - + - ``bank`` is the filter bank that is to be cleared. .. method:: can.any(fifo) @@ -120,22 +120,56 @@ Methods .. method:: can.recv(fifo, \*, timeout=5000) Receive data on the bus: - + - ``fifo`` is an integer, which is the FIFO to receive on - ``timeout`` is the timeout in milliseconds to wait for the receive. - + Return value: buffer of data bytes. .. method:: can.send(send, addr, \*, timeout=5000) Send a message on the bus: - + - ``send`` is the data to send (an integer to send, or a buffer object). - ``addr`` is the address to send to - ``timeout`` is the timeout in milliseconds to wait for the send. - + Return value: ``None``. +.. method:: can.rxcallback(fifo, fun) + + Register a function to be called when a message is accepted into a empty fifo: + + - ``fifo`` is the receiving fifo. + - ``fun`` is the function to be called when the fifo becomes non empty. + + The callback function takes two arguments the first is the can object it self the second is + a integer that indicates the reason for the callback. + + +--------+------------------------------------------------+ + | Reason | | + +========+================================================+ + | 0 | A message has been accepted into a empty FIFO. | + +--------+------------------------------------------------+ + | 1 | The FIFO is full | + +--------+------------------------------------------------+ + | 2 | A message has been lost due to a full FIFO | + +--------+------------------------------------------------+ + + Example use of rxcallback:: + + def cb0(bus, reason): + print('cb0') + if reason == 0: + print('pending') + if reason == 1: + print('full') + if reason == 2: + print('overflow') + + can = CAN(1, CAN.LOOPBACK) + can.rxcallback(0, cb0) + Constants --------- @@ -151,4 +185,4 @@ Constants .. data:: CAN.LIST32 .. data:: CAN.MASK32 - the operation mode of a filter + the operation mode of a filter |