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Handle multiple HALLCONF values (Resolves #19) #27

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Merged
merged 3 commits into from
Mar 2, 2021
Merged

Handle multiple HALLCONF values (Resolves #19) #27

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74ed904
Add HALLCONF=0x0 calibration data to _LSB_LOOKUP
SAK917 Mar 1, 2021
bb275d9
Revert "Add HALLCONF=0x0 calibration data to _LSB_LOOKUP"
SAK917 Mar 1, 2021
180f091
Handle multiple HALLCONF values
SAK917 Mar 2, 2021
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74 changes: 53 additions & 21 deletions adafruit_mlx90393.py
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Original file line number Diff line number Diff line change
Expand Up @@ -93,31 +93,55 @@
OSR_2 = 0x2
OSR_3 = 0x3

_HALLCONF = const(0x0C) # Hall plate spinning rate adjust.
# Hall plate spinning rate adjustment
# Must be 0x0C (default) or 0x00
_HALLCONF = const(0x0C)

STATUS_OK = 0x3

# The lookup table below allows you to convert raw sensor data to uT
# using the appropriate (gain/resolution-dependant) lsb-per-uT
# coefficient below. Note that the z axis has a different coefficient
# than the x and y axis. Assumes HALLCONF = 0x0C!
# than the x and y axis.
_LSB_LOOKUP = (
# 5x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.751, 1.210), (1.502, 2.420), (3.004, 4.840), (6.009, 9.680)),
# 4x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.601, 0.968), (1.202, 1.936), (2.403, 3.872), (4.840, 7.744)),
# 3x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.451, 0.726), (0.901, 1.452), (1.803, 2.904), (3.605, 5.808)),
# 2.5x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.376, 0.605), (0.751, 1.210), (1.502, 2.420), (3.004, 4.840)),
# 2x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.300, 0.484), (0.601, 0.968), (1.202, 1.936), (2.403, 3.872)),
# 1.667x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.250, 0.403), (0.501, 0.807), (1.001, 1.613), (2.003, 3.227)),
# 1.333x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.200, 0.323), (0.401, 0.645), (0.801, 1.291), (1.602, 2.581)),
# 1x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.150, 0.242), (0.300, 0.484), (0.601, 0.968), (1.202, 1.936)),
# HALLCONF = 0x0C (default)
(
# 5x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.751, 1.210), (1.502, 2.420), (3.004, 4.840), (6.009, 9.680)),
# 4x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.601, 0.968), (1.202, 1.936), (2.403, 3.872), (4.840, 7.744)),
# 3x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.451, 0.726), (0.901, 1.452), (1.803, 2.904), (3.605, 5.808)),
# 2.5x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.376, 0.605), (0.751, 1.210), (1.502, 2.420), (3.004, 4.840)),
# 2x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.300, 0.484), (0.601, 0.968), (1.202, 1.936), (2.403, 3.872)),
# 1.667x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.250, 0.403), (0.501, 0.807), (1.001, 1.613), (2.003, 3.227)),
# 1.333x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.200, 0.323), (0.401, 0.645), (0.801, 1.291), (1.602, 2.581)),
# 1x gain: res0(xy)(z), res1(xy)(z), res2(xy)(z), res3(xy)(z)
((0.150, 0.242), (0.300, 0.484), (0.601, 0.968), (1.202, 1.936)),
),
# HALLCONF = 0x00
(
# GAIN_SEL = 0, 5x gain
((0.787, 1.267), (1.573, 2.534), (3.146, 5.068), (6.292, 10.137)),
# GAIN_SEL = 1, 4x gain
((0.629, 1.014), (1.258, 2.027), (2.517, 4.055), (5.034, 8.109)),
# GAIN_SEL = 2, 3x gain
((0.472, 0.760), (0.944, 1.521), (1.888, 3.041), (3.775, 6.082)),
# GAIN_SEL = 3, 2.5x gain
((0.393, 0.634), (0.787, 1.267), (1.573, 2.534), (3.146, 5.068)),
# GAIN_SEL = 4, 2x gain
((0.315, 0.507), (0.629, 1.014), (1.258, 2.027), (2.517, 4.055)),
# GAIN_SEL = 5, 1.667x gain
((0.262, 0.422), (0.524, 0.845), (1.049, 1.689), (2.097, 3.379)),
# GAIN_SEL = 6, 1.333x gain
((0.210, 0.338), (0.419, 0.676), (0.839, 1.352), (1.678, 2.703)),
# GAIN_SEL = 7, 1x gain
((0.157, 0.253), (0.315, 0.507), (0.629, 1.014), (1.258, 2.027)),
),
)

# Lookup table for conversion times for different filter and
Expand Down Expand Up @@ -442,9 +466,17 @@ def magnetic(self):
"""
x, y, z = self.read_data

# Check for valid HALLCONF value and set _LSB_LOOKUP index
if _HALLCONF == 0x0C:
hallconf_index = 0
elif _HALLCONF == 0x00:
hallconf_index = 1
else:
raise ValueError("Incorrect HALLCONF value, must be '0x0C' or '0x00'.")

# Convert the raw integer values to uT based on gain and resolution
x *= _LSB_LOOKUP[self._gain_current][self._res_x][0]
y *= _LSB_LOOKUP[self._gain_current][self._res_y][0]
z *= _LSB_LOOKUP[self._gain_current][self._res_z][1]
x *= _LSB_LOOKUP[hallconf_index][self._gain_current][self._res_x][0]
y *= _LSB_LOOKUP[hallconf_index][self._gain_current][self._res_y][0]
z *= _LSB_LOOKUP[hallconf_index][self._gain_current][self._res_z][1]

return x, y, z