diff options
| -rw-r--r-- | stmhal/i2c.c | 45 | ||||
| -rw-r--r-- | stmhal/spi.c | 22 | ||||
| -rw-r--r-- | stmhal/usart.c | 15 |
3 files changed, 82 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) diff --git a/stmhal/spi.c b/stmhal/spi.c index 352c594c9e..99bc08c3b1 100644 --- a/stmhal/spi.c +++ b/stmhal/spi.c @@ -14,6 +14,25 @@ #include "bufhelper.h" #include "spi.h" +// Usage model: +// +// See usage model of I2C in i2c.c. SPI is very similar. Main difference is +// parameters to init the SPI bus: +// +// from pyb import SPI +// spi = SPI(1, SPI.MASTER, baudrate=600000, polarity=1, phase=1, crc=0x7) +// +// Only required parameter is mode, SPI.MASTER or SPI.SLAVE. Polarity can be +// 0 or 1, and is the level the idle clock line sits at. Phase can be 1 or 2 +// for number of edges. Crc can be None for no CRC, or a polynomial specifier. +// +// Additional method for SPI: +// +// data = spi.send_recv(b'1234') # send 4 bytes and receive 4 bytes +// buf = bytearray(4) +// spi.send_recv(b'1234', buf) # send 4 bytes and receive 4 into buf +// spi.send_recv(buf, buf) # send/recv 4 bytes from/to buf + #if MICROPY_HW_ENABLE_SPI1 SPI_HandleTypeDef SPIHandle1 = {.Instance = NULL}; #endif @@ -384,6 +403,9 @@ STATIC mp_obj_t pyb_spi_send_recv(uint n_args, const mp_obj_t *args, mp_map_t *k } else { // recv argument given mp_get_buffer_raise(vals[1].u_obj, &bufinfo_recv, MP_BUFFER_WRITE); + if (bufinfo_recv.len != bufinfo_send.len) { + nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "recv must be same length as send")); + } o_ret = MP_OBJ_NULL; } } diff --git a/stmhal/usart.c b/stmhal/usart.c index c737955ac2..4e5502aa35 100644 --- a/stmhal/usart.c +++ b/stmhal/usart.c @@ -12,6 +12,21 @@ #include "bufhelper.h" #include "usart.h" +// Usage model: +// +// See usage model of I2C in i2c.c. USART is very similar. Main difference is +// parameters to init the USART bus: +// +// from pyb import USART +// usart = USART(1, 9600) # init with given baudrate +// usart.init(9600, bits=8, stop=1, parity=None) # init with given parameters +// +// Bits can be 8 or 9, stop can be 1 or 2, parity can be None, 0 (even), 1 (odd). +// +// Extra method: +// +// usart.any() # returns True if any characters waiting + struct _pyb_usart_obj_t { mp_obj_base_t base; pyb_usart_t usart_id; |