def _mag_callback(self):
'''
Update magnetometer Vector3d object (if data available)
'''
try: # If read fails, returns last valid data
if self.mag_ready: # Starts mag if necessary
self._read(self.buf6, 0x03, self._mag_addr)
self.mag_triggered = False
else:
self._mag_stale_count += 1 # Data not ready: retain last value
return # but increment stale count
self._read(self.buf6, 0x03, self._mag_addr) # Mag was ready
self._read(self.buf1, 0x09, self._mag_addr) # Read ST2
except OSError:
self.mag_triggered = False
raise MPUException(self._I2Cerror)
if self.buf1[0] & 0x0C > 0: # An overflow or data error has occurred
self._mag_stale_count += 1 # transitory condition? User checks stale count.
return
self._mag._ivector[1] = bytes_toint(self.buf6[1], self.buf6[0]) # Note axis twiddling and little endian
self._mag._ivector[0] = bytes_toint(self.buf6[3], self.buf6[2])
self._mag._ivector[2] = -bytes_toint(self.buf6[5], self.buf6[4])
scale = 0.3 # 0.3uT/LSB
self._mag._vector[0] = self._mag._ivector[0]*self.mag_correction[0]*scale
self._mag._vector[1] = self._mag._ivector[1]*self.mag_correction[1]*scale
self._mag._vector[2] = self._mag._ivector[2]*self.mag_correction[2]*scale
self._mag_stale_count = 0
def get_mag_irq(self):
'''
Uncorrected values because floating point uses heap
'''
if not self.mag_triggered: # Can't do exception handling here
self._write(1, 0x0A, self._mag_addr)
self.mag_triggered = True
self._read(self.buf1, 0x02, self._mag_addr)
if self.buf1[0] == 1:
self._read(self.buf6, 0x03, self._mag_addr) # Note axis twiddling
self._mag._ivector[1] = bytes_toint(self.buf6[1], self.buf6[0])
self._mag._ivector[0] = bytes_toint(self.buf6[3], self.buf6[2])
self._mag._ivector[2] = -bytes_toint(self.buf6[5], self.buf6[4])
self.mag_triggered = False
def temperature(self):
'''
Returns the temperature in degree C.
'''
try:
self._read(self.buf2, 0x41, self.mpu_addr)
except OSError:
raise MPUException(self._I2Cerror)
return bytes_toint(self.buf2[0], self.buf2[1])/340 + 35 # I think
