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from machine import SPI
# configure the SPI master @ 2MHz
# this uses the SPI non-default pins for CLK, MOSI and MISO (``P19``, ``P20`` and ``P2
1``)
spi = SPI( 0 , mode=SPI.MASTER, baudrate= 2000000 , polarity= 0 , phase= 0 , pins=( 'P19' , 'P20' ,
'P21' ))
spi.write(bytes([ 0x01 , 0x02 , 0x03 , 0x04 , 0x05 ])) # send 5 bytes on the bus
spi.read( 5 ) # receive 5 bytes on the bus
rbuf = bytearray( 5 )
spi.write_readinto(bytes([ 0x01 , 0x02 , 0x03 , 0x04 , 0x05 ]), rbuf) # send a receive 5 byt
es
Constructors
class machine.SPI(id, ...)
Construct an SPI object on the given bus.
id
can be only 0. 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
spi.init(mode, baudrate=1000000, * , polarity=0, phase=0, bits=8, firstbit=SPI.MSB,
pins=(CLK, MOSI, MISO))
Initialise the SPI bus with the given parameters:
mode
must be SPI.MASTER.
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 of each transfer, accepted values are 8, 16 and 32.
firstbit
can be SPI.MSB or SPI.LSB.
pins
is an optional tuple with the pins to assign to the SPI bus. If the pins argument is
not given the default pins will be selected (
P10
as CLK,
P11
as MOSI and
P14
as
MISO). If pins is passed as None then no pin assignment will be made.
spi.deinit()
Turn off the SPI bus.
spi.write(buf)
5.2.1.7 SPI
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