55 lines
1.7 KiB
Arduino
55 lines
1.7 KiB
Arduino
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/*
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The sensor outputs provided by the library are the raw 16-bit values
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obtained by concatenating the 8-bit high and low accelerometer and
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magnetometer data registers. They can be converted to units of g and
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gauss using the conversion factors specified in the datasheet for your
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particular device and full scale setting (gain).
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Example: An LSM303D gives a magnetometer X axis reading of 1982 with
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its default full scale setting of +/- 4 gauss. The M_GN specification
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in the LSM303D datasheet (page 10) states a conversion factor of 0.160
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mgauss/LSB (least significant bit) at this FS setting, so the raw
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reading of -1982 corresponds to 1982 * 0.160 = 317.1 mgauss =
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0.3171 gauss.
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In the LSM303DLHC, LSM303DLM, and LSM303DLH, the acceleration data
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registers actually contain a left-aligned 12-bit number, so the lowest
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4 bits are always 0, and the values should be shifted right by 4 bits
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(divided by 16) to be consistent with the conversion factors specified
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in the datasheets.
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Example: An LSM303DLH gives an accelerometer Z axis reading of -16144
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with its default full scale setting of +/- 2 g. Dropping the lowest 4
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bits gives a 12-bit raw value of -1009. The LA_So specification in the
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LSM303DLH datasheet (page 11) states a conversion factor of 1 mg/digit
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at this FS setting, so the value of -1009 corresponds to -1009 * 1 =
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1009 mg = 1.009 g.
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*/
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#include <Wire.h>
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#include "LSM303.h"
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LSM303 compass;
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char report[80];
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void setup()
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{
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Serial.begin(9600);
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Wire.begin();
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compass.init();
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compass.enableDefault();
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}
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void loop()
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{
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compass.read();
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snprintf(report, sizeof(report), "A: %6d %6d %6d M: %6d %6d %6d",
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compass.a.x, compass.a.y, compass.a.z,
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compass.m.x, compass.m.y, compass.m.z);
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Serial.println(report);
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delay(100);
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}
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