class HMC5883L:
# Register map based on Jeff Rowberg <*****@*****.**> source code at
# https://github.com/jrowberg/i2cdevlib/
HMC5883L_ADDRESS = 0x1E # this device only has one address
HMC5883L_DEFAULT_ADDRESS = 0x1E
HMC5883L_RA_CONFIG_A = 0x00
HMC5883L_RA_CONFIG_B = 0x01
HMC5883L_RA_MODE = 0x02
HMC5883L_RA_DATAX_H = 0x03
HMC5883L_RA_DATAX_L = 0x04
HMC5883L_RA_DATAZ_H = 0x05
HMC5883L_RA_DATAZ_L = 0x06
HMC5883L_RA_DATAY_H = 0x07
HMC5883L_RA_DATAY_L = 0x08
HMC5883L_RA_STATUS = 0x09
HMC5883L_RA_ID_A = 0x0A
HMC5883L_RA_ID_B = 0x0B
HMC5883L_RA_ID_C = 0x0C
HMC5883L_CRA_AVERAGE_BIT = 6
HMC5883L_CRA_AVERAGE_LENGTH = 2
HMC5883L_CRA_RATE_BIT = 4
HMC5883L_CRA_RATE_LENGTH = 3
HMC5883L_CRA_BIAS_BIT = 1
HMC5883L_CRA_BIAS_LENGTH = 2
HMC5883L_AVERAGING_1 = 0x00
HMC5883L_AVERAGING_2 = 0x01
HMC5883L_AVERAGING_4 = 0x02
HMC5883L_AVERAGING_8 = 0x03
HMC5883L_RATE_0P75 = 0x00
HMC5883L_RATE_1P5 = 0x01
HMC5883L_RATE_3 = 0x02
HMC5883L_RATE_7P5 = 0x03
HMC5883L_RATE_15 = 0x04
HMC5883L_RATE_30 = 0x05
HMC5883L_RATE_75 = 0x06
HMC5883L_BIAS_NORMAL = 0x00
HMC5883L_BIAS_POSITIVE = 0x01
HMC5883L_BIAS_NEGATIVE = 0x02
HMC5883L_CRB_GAIN_BIT = 7
HMC5883L_CRB_GAIN_LENGTH = 3
HMC5883L_GAIN_1370 = 0x00
HMC5883L_GAIN_1090 = 0x01
HMC5883L_GAIN_820 = 0x02
HMC5883L_GAIN_660 = 0x03
HMC5883L_GAIN_440 = 0x04
HMC5883L_GAIN_390 = 0x05
HMC5883L_GAIN_330 = 0x06
HMC5883L_GAIN_220 = 0x07
HMC5883L_MODEREG_BIT = 1
HMC5883L_MODEREG_LENGTH = 2
HMC5883L_MODE_CONTINUOUS = 0x00
HMC5883L_MODE_SINGLE = 0x01
HMC5883L_MODE_IDLE = 0x02
HMC5883L_STATUS_LOCK_BIT = 1
HMC5883L_STATUS_READY_BIT = 0
mode = 0
def __init__(self, address=HMC5883L_DEFAULT_ADDRESS):
self.i2c = PyComms(address)
self.address = address
def initialize(self):
# write CONFIG_A register
self.i2c.write8(
self.HMC5883L_RA_CONFIG_A,
(self.HMC5883L_AVERAGING_8 <<
(self.HMC5883L_CRA_AVERAGE_BIT -
self.HMC5883L_CRA_AVERAGE_LENGTH + 1)) |
(self.HMC5883L_RATE_15 <<
(self.HMC5883L_CRA_RATE_BIT - self.HMC5883L_CRA_RATE_LENGTH + 1))
|
(self.HMC5883L_BIAS_NORMAL <<
(self.HMC5883L_CRA_BIAS_BIT - self.HMC5883L_CRA_BIAS_LENGTH + 1)))
# write CONFIG_B register
self.setGain(self.HMC5883L_GAIN_1090)
# write MODE register
self.setMode(self.HMC5883L_MODE_SINGLE)
def testConnection(self):
pass
def getSampleAveraging(self):
pass
def setSampleAveraging(self, value):
self.i2c.writeBits(self.HMC5883L_RA_CONFIG_A,
self.HMC5883L_CRA_AVERAGE_BIT,
self.HMC5883L_CRA_AVERAGE_LENGTH, value)
def getDataRate(self):
pass
def setDataRate(self, value):
self.i2c.writeBits(self.HMC5883L_RA_CONFIG_A,
self.HMC5883L_CRA_RATE_BIT,
self.HMC5883L_CRA_RATE_LENGTH, value)
def getMeasurementBias(self):
pass
def setMeasurementBias(self, value):
self.i2c.writeBits(self.HMC5883L_RA_CONFIG_A,
self.HMC5883L_CRA_BIAS_BIT,
self.HMC5883L_CRA_BIAS_LENGTH, value)
def getGain(self):
pass
def setGain(self, value):
self.i2c.write8(
self.HMC5883L_RA_CONFIG_B, value <<
(self.HMC5883L_CRB_GAIN_BIT - self.HMC5883L_CRB_GAIN_LENGTH + 1))
def getMode(self):
pass
def setMode(self, newMode):
# use this method to guarantee that bits 7-2 are set to zero, which is a
# requirement specified in the datasheet
self.i2c.write8(
self.HMC5883L_RA_MODE, self.mode <<
(self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
self.mode = newMode # track to tell if we have to clear bit 7 after a read
def getHeading(self):
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(
self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE <<
(self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
data = {
'x': ((packet[0] << 8) | packet[1]),
'y': ((packet[4] << 8) | packet[5]),
'z': ((packet[2] << 8) | packet[3])
}
return data
def getHeadingX(self):
# each axis read requires that ALL axis registers be read, even if only
# one is used; this was not done ineffiently in the code by accident
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(
self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE <<
(self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
return ((packet[0] << 8) | packet[1])
def getHeadingY(self):
# each axis read requires that ALL axis registers be read, even if only
# one is used; this was not done ineffiently in the code by accident
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(
self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE <<
(self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
return ((packet[4] << 8) | packet[5])
def getHeadingZ(self):
# each axis read requires that ALL axis registers be read, even if only
# one is used; this was not done ineffiently in the code by accident
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(
self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE <<
(self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
return ((packet[2] << 8) | packet[3])
def getLockStatus(self):
result = self.i2c.readBit(self.HMC5883L_RA_STATUS,
self.HMC5883L_STATUS_LOCK_BIT)
return result
def getReadyStatus(self):
result = self.i2c.readBit(self.HMC5883L_RA_STATUS,
self.HMC5883L_STATUS_READY_BIT)
return result
def getIDA(self):
result = self.i2c.readByte(self.HMC5883L_RA_ID_A)
return result
def getIDB(self):
result = self.i2c.readByte(self.HMC5883L_RA_ID_B)
return result
def getIDC(self):
result = self.i2c.readByte(self.HMC5883L_RA_ID_C)
return result
class HMC5883L:
# Register map based on Jeff Rowberg <*****@*****.**> source code at
# https://github.com/jrowberg/i2cdevlib/
HMC5883L_ADDRESS = 0x1E # this device only has one address
HMC5883L_DEFAULT_ADDRESS = 0x1E
HMC5883L_RA_CONFIG_A = 0x00
HMC5883L_RA_CONFIG_B = 0x01
HMC5883L_RA_MODE = 0x02
HMC5883L_RA_DATAX_H = 0x03
HMC5883L_RA_DATAX_L = 0x04
HMC5883L_RA_DATAZ_H = 0x05
HMC5883L_RA_DATAZ_L = 0x06
HMC5883L_RA_DATAY_H = 0x07
HMC5883L_RA_DATAY_L = 0x08
HMC5883L_RA_STATUS = 0x09
HMC5883L_RA_ID_A = 0x0A
HMC5883L_RA_ID_B = 0x0B
HMC5883L_RA_ID_C = 0x0C
HMC5883L_CRA_AVERAGE_BIT = 6
HMC5883L_CRA_AVERAGE_LENGTH = 2
HMC5883L_CRA_RATE_BIT = 4
HMC5883L_CRA_RATE_LENGTH = 3
HMC5883L_CRA_BIAS_BIT = 1
HMC5883L_CRA_BIAS_LENGTH = 2
HMC5883L_AVERAGING_1 = 0x00
HMC5883L_AVERAGING_2 = 0x01
HMC5883L_AVERAGING_4 = 0x02
HMC5883L_AVERAGING_8 = 0x03
HMC5883L_RATE_0P75 = 0x00
HMC5883L_RATE_1P5 = 0x01
HMC5883L_RATE_3 = 0x02
HMC5883L_RATE_7P5 = 0x03
HMC5883L_RATE_15 = 0x04
HMC5883L_RATE_30 = 0x05
HMC5883L_RATE_75 = 0x06
HMC5883L_BIAS_NORMAL = 0x00
HMC5883L_BIAS_POSITIVE = 0x01
HMC5883L_BIAS_NEGATIVE = 0x02
HMC5883L_CRB_GAIN_BIT = 7
HMC5883L_CRB_GAIN_LENGTH = 3
HMC5883L_GAIN_1370 = 0x00
HMC5883L_GAIN_1090 = 0x01
HMC5883L_GAIN_820 = 0x02
HMC5883L_GAIN_660 = 0x03
HMC5883L_GAIN_440 = 0x04
HMC5883L_GAIN_390 = 0x05
HMC5883L_GAIN_330 = 0x06
HMC5883L_GAIN_220 = 0x07
HMC5883L_MODEREG_BIT = 1
HMC5883L_MODEREG_LENGTH = 2
HMC5883L_MODE_CONTINUOUS = 0x00
HMC5883L_MODE_SINGLE = 0x01
HMC5883L_MODE_IDLE = 0x02
HMC5883L_STATUS_LOCK_BIT = 1
HMC5883L_STATUS_READY_BIT = 0
mode = 0
def __init__(self, address = HMC5883L_DEFAULT_ADDRESS):
self.i2c = PyComms(address)
self.address = address
def initialize(self):
# write CONFIG_A register
self.i2c.write8(self.HMC5883L_RA_CONFIG_A,
(self.HMC5883L_AVERAGING_8 << (self.HMC5883L_CRA_AVERAGE_BIT - self.HMC5883L_CRA_AVERAGE_LENGTH + 1)) |
(self.HMC5883L_RATE_15 << (self.HMC5883L_CRA_RATE_BIT - self.HMC5883L_CRA_RATE_LENGTH + 1)) |
(self.HMC5883L_BIAS_NORMAL << (self.HMC5883L_CRA_BIAS_BIT - self.HMC5883L_CRA_BIAS_LENGTH + 1)))
# write CONFIG_B register
self.setGain(self.HMC5883L_GAIN_1090);
# write MODE register
self.setMode(self.HMC5883L_MODE_SINGLE);
def testConnection(self):
pass
def getSampleAveraging(self):
pass
def setSampleAveraging(self, value):
self.i2c.writeBits(self.HMC5883L_RA_CONFIG_A, self.HMC5883L_CRA_AVERAGE_BIT, self.HMC5883L_CRA_AVERAGE_LENGTH, value)
def getDataRate(self):
pass
def setDataRate(self, value):
self.i2c.writeBits(self.HMC5883L_RA_CONFIG_A, self.HMC5883L_CRA_RATE_BIT, self.HMC5883L_CRA_RATE_LENGTH, value)
def getMeasurementBias(self):
pass
def setMeasurementBias(self, value):
self.i2c.writeBits(self.HMC5883L_RA_CONFIG_A, self.HMC5883L_CRA_BIAS_BIT, self.HMC5883L_CRA_BIAS_LENGTH, value);
def getGain(self):
pass
def setGain(self, value):
self.i2c.write8(self.HMC5883L_RA_CONFIG_B, value << (self.HMC5883L_CRB_GAIN_BIT - self.HMC5883L_CRB_GAIN_LENGTH + 1))
def getMode(self):
pass
def setMode(self, newMode):
# use this method to guarantee that bits 7-2 are set to zero, which is a
# requirement specified in the datasheet
self.i2c.write8(self.HMC5883L_RA_MODE, self.mode << (self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
self.mode = newMode # track to tell if we have to clear bit 7 after a read
def getHeading(self):
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE << (self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
data = {
'x' : ((packet[0] << 8) | packet[1]),
'y' : ((packet[4] << 8) | packet[5]),
'z' : ((packet[2] << 8) | packet[3])}
return data
def getHeadingX(self):
# each axis read requires that ALL axis registers be read, even if only
# one is used; this was not done ineffiently in the code by accident
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE << (self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
return ((packet[0] << 8) | packet[1])
def getHeadingY(self):
# each axis read requires that ALL axis registers be read, even if only
# one is used; this was not done ineffiently in the code by accident
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE << (self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
return ((packet[4] << 8) | packet[5])
def getHeadingZ(self):
# each axis read requires that ALL axis registers be read, even if only
# one is used; this was not done ineffiently in the code by accident
packet = self.i2c.readBytesListS(self.HMC5883L_RA_DATAX_H, 6)
if (self.mode == self.HMC5883L_MODE_SINGLE):
self.i2c.write8(self.HMC5883L_RA_MODE, self.HMC5883L_MODE_SINGLE << (self.HMC5883L_MODEREG_BIT - self.HMC5883L_MODEREG_LENGTH + 1))
return ((packet[2] << 8) | packet[3])
def getLockStatus(self):
result = self.i2c.readBit(self.HMC5883L_RA_STATUS, self.HMC5883L_STATUS_LOCK_BIT)
return result
def getReadyStatus(self):
result = self.i2c.readBit(self.HMC5883L_RA_STATUS, self.HMC5883L_STATUS_READY_BIT)
return result
def getIDA(self):
result = self.i2c.readByte(self.HMC5883L_RA_ID_A)
return result
def getIDB(self):
result = self.i2c.readByte(self.HMC5883L_RA_ID_B)
return result
def getIDC(self):
result = self.i2c.readByte(self.HMC5883L_RA_ID_C)
return result
