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stmhal: Working STM32F4DISC accelerometer, via Python script.

Browse Source 
Thanks to David Siorpaes.
This commit is contained in:
Damien George 2014-08-10 22:26:20 +01:00
parent 4ef26c14b1
commit 101d87da6a
1 changed files with 18 additions and 4 deletions
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22
stmhal/boards/STM32F4DISC/staccel.py Normal file → Executable file
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@ -2,8 +2,8 @@
Driver for accelerometer on STM32F4 Discover board.
Assumes it's a LIS302DL MEMS device.
Not currently working.
Sets accelerometer range at +-2g.
Returns list containing X,Y,Z axis acceleration values in 'g' units (9.8m/s^2).
See:
STM32Cube_FW_F4_V1.1.0/Drivers/BSP/Components/lis302dl/lis302dl.h
@ -22,12 +22,22 @@ READWRITE_CMD = const(0x80)
MULTIPLEBYTE_CMD = const(0x40)
LIS302DL_WHO_AM_I_ADDR = const(0x0f)
LIS302DL_CTRL_REG1_ADDR = const(0x20)
LIS302DL_OUT_X = const(0x29)
# Configuration for 100Hz sampling rate, +-2g range
LIS302DL_CONF = 0b01000111
def signed8(x):
if x & 0x80:
return x - 256
else:
return x
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)
self.wr(LIS302DL_CTRL_REG1_ADDR, bytearray([LIS302DL_CONF]))
def rd(self, addr, nbytes):
if nbytes > 1:
@ -52,5 +62,9 @@ class STAccel:
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]))
def get_xyz(self):
val = self.rd(LIS302DL_OUT_X, 5)
x = signed8(val[0]) * 18.0 / 1000
y = signed8(val[2]) * 18.0 / 1000
z = signed8(val[4]) * 18.0 / 1000
return [x, y, z]