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Diffstat (limited to 'stmhal/i2c.c')
| -rw-r--r-- | stmhal/i2c.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/stmhal/i2c.c b/stmhal/i2c.c index d94a99ee9e..b6e3d9beee 100644 --- a/stmhal/i2c.c +++ b/stmhal/i2c.c @@ -14,6 +14,51 @@ #include "bufhelper.h" #include "i2c.h" +// Usage model: +// +// I2C objects are created attached to a specific bus. They can be initialised +// when created, or initialised later on: +// +// from pyb import I2C +// +// i2c = I2C(1) # create on bus 1 +// i2c = I2C(1, I2C.MASTER) # create and init as a master +// i2c.deinit() # turn off the peripheral +// i2c.init(I2C.MASTER, baudrate=20000) # init as a master +// i2c.init(I2C.SLAVE, addr=0x42) # init as a slave with given address +// +// Printing the i2c object gives you information about its configuration. +// +// Basic methods for slave are send and recv: +// +// i2c.send('abc') # send 3 bytes +// i2c.send(0x42) # send a single byte, given by the number +// data = i2c.recv(3) # receive 3 bytes +// +// To receive inplace, first create a bytearray: +// +// data = bytearray(3) # create a buffer +// i2c.recv(data) # receive 3 bytes, writing them into data +// +// You can specify a timeout (in ms): +// +// i2c.send(b'123', timeout=2000) # timout after 2 seconds +// +// A master must specify the recipient's address: +// +// i2c.init(I2C.MASTER) +// i2c.send('123', 0x42) # send 3 bytes to slave with address 0x42 +// i2c.send(b'456', addr=0x42) # keyword for address +// +// Master also has other methods: +// +// i2c.is_ready(0x42) # check if slave 0x42 is ready +// i2c.scan() # scan for slaves on the bus, returning +// # a list of valid addresses +// i2c.mem_read(3, 0x42, 2) # read 3 bytes from memory of slave 0x42, +// # starting at address 2 in the slave +// i2c.mem_write('abc', 0x42, 2, timeout=1000) + #define PYB_I2C_MASTER (0) #define PYB_I2C_SLAVE (1) |