stmhal: Add preliminary driver for ST32F4DISC accelerometer.

Written in Python, not currently working.  See issue #725.
This commit is contained in:
Damien George 2014-08-02 12:51:18 +01:00
parent 8464be15ed
commit 71bed1a9a7

View File

@ -0,0 +1,56 @@
"""
Driver for accelerometer on STM32F4 Discover board.
Assumes it's a LIS302DL MEMS device.
Not currently working.
See:
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/Components/lis302dl/lis302dl.h
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/Components/lis302dl/lis302dl.c
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/STM32F4-Discovery/stm32f4_discovery.c
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/STM32F4-Discovery/stm32f4_discovery.h
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/STM32F4-Discovery/stm32f4_discovery_accelerometer.c
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/STM32F4-Discovery/stm32f4_discovery_accelerometer.h
STM32Cube_FW_F4_V1.1.0/Projects/STM32F4-Discovery/Demonstrations/Src/main.c
"""
from pyb import Pin
from pyb import SPI
READWRITE_CMD = const(0x80)
MULTIPLEBYTE_CMD = const(0x40)
LIS302DL_WHO_AM_I_ADDR = const(0x0f)
LIS302DL_CTRL_REG1_ADDR = const(0x20)
class STAccel:
def __init__(self):
self.cs_pin = Pin('PE3', Pin.OUT_PP, Pin.PULL_NONE)
self.cs_pin.high()
self.spi = SPI(1, SPI.MASTER, baudrate=328125, polarity=0, phase=1, bits=8)
def rd(self, addr, nbytes):
if nbytes > 1:
addr |= READWRITE_CMD | MULTIPLEBYTE_CMD
else:
addr |= READWRITE_CMD
self.cs_pin.low()
self.spi.send(addr)
buf = self.spi.send_recv(bytearray(nbytes * [0])) # read data, MSB first
self.cs_pin.high()
return buf
def wr(self, addr, buf):
if len(buf) > 1:
addr |= MULTIPLEBYTE_CMD
self.cs_pin.low()
self.spi.send(addr)
for b in buf:
self.spi.send(b)
self.cs_pin.high()
def read_id(self):
return self.rd(LIS302DL_WHO_AM_I_ADDR, 1)
def init(self, init_param):
self.wr(LIS302DL_CTRL_REG1_ADDR, bytearray([init_param]))