Pololu Minimu-9 library
Diff: LSM303.cpp
- Revision:
- 0:6ee4ef99c382
diff -r 000000000000 -r 6ee4ef99c382 LSM303.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/LSM303.cpp Tue Feb 21 13:34:27 2012 +0000 @@ -0,0 +1,209 @@ +/* mbed LSM303 Library version 0beta1 + * Copyright (c) 2012 bengo + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include <LSM303.h> +#include <cmath> + +// LSM303 I2C addresses +const int LSM303::ACC_ADDRESS = 0x30; +const int LSM303::MAG_ADDRESS = 0x3c; +// LSM303 register addresses +const int LSM303::ACC_CTRL_REG1 = 0x20; +const int LSM303::ACC_CTRL_REG2 = 0x21; +const int LSM303::ACC_CTRL_REC3 = 0x22; +const int LSM303::ACC_CTRL_REG4 = 0x23; +const int LSM303::ACC_CTRL_REG5 = 0x24; +const int LSM303::ACC_HP_FILTER_RESET = 0x25; +const int LSM303::ACC_REFERENCE = 0x26; +const int LSM303::ACC_STATUS_REG = 0x27; +const int LSM303::ACC_OUT_X_L = 0x28; +const int LSM303::ACC_OUT_X_H = 0x29; +const int LSM303::ACC_OUT_Y_L = 0x2a; +const int LSM303::ACC_OUT_Y_H = 0x2b; +const int LSM303::ACC_OUT_Z_L = 0x2c; +const int LSM303::ACC_OUT_Z_H = 0x2d; +const int LSM303::ACC_INT1_CFG = 0x30; +const int LSM303::ACC_INT1_SOURCE = 0x31; +const int LSM303::ACC_INT1_THS = 0x32; +const int LSM303::ACC_INT1_DURATION = 0x33; +const int LSM303::ACC_INT2_CFG = 0x34; +const int LSM303::ACC_INT2_SOURCE = 0x35; +const int LSM303::ACC_INT2_THS = 0x36; +const int LSM303::ACC_INT2_DURATION = 0x37; +const int LSM303::MAG_CRA_REG = 0x00; +const int LSM303::MAG_CRB_REG = 0x01; +const int LSM303::MAG_MR_REG = 0x02; +const int LSM303::MAG_OUT_X_H = 0x03; +const int LSM303::MAG_OUT_X_L = 0x04; +const int LSM303::MAG_OUT_Y_H = 0x07; +const int LSM303::MAG_OUT_Y_L = 0x08; +const int LSM303::MAG_OUT_Z_H = 0x05; +const int LSM303::MAG_OUT_Z_L = 0x6; +const int LSM303::MAG_SR_REG = 0x9; +const int LSM303::MAG_IRA_REG = 0xa; +const int LSM303::MAG_IRB_REG = 0xb; +const int LSM303::MAG_IRC_REG = 0xc; +const int LSM303::MAG_WHO_AM_I = 0xf; +// + +// ------------------------------------------- +LSM303::LSM303( PinName sda, PinName scl ) : _i2c( sda, scl ) { + // Get SA0 pin status + _bytes[0] = ACC_CTRL_REG1; + _i2c.write( ACC_ADDRESS, _bytes, 1 ); + int sa0low = _i2c.read( ACC_ADDRESS+1, _bytes, 1 ); + _bytes[0] = ACC_CTRL_REG1; + _i2c.write( ACC_ADDRESS+2, _bytes, 1 ); + int sa0hig = _i2c.read( ACC_ADDRESS+2+1, _bytes, 1 ); + if( sa0low == 0 && sa0hig != 0 ) { + _SA0Pad = 0x0; + } + else if( sa0low != 0 && sa0hig == 0 ) { + _SA0Pad = 0x2; + } + else { + _status = 1; + return; + } + // Check that you're talking with an LM303DLM device + _bytes[0] = MAG_WHO_AM_I; + _i2c.write( MAG_ADDRESS, _bytes, 1 ); + _status = _i2c.read( MAG_ADDRESS+1, _bytes, 1 ); + if( _bytes[0] == 0x3c ) { + _status = 0; + } + else { + _status = 1; + return; + } + // Enable normal mode... + // ... On accelerometer + this->accRegisterWrite( ACC_CTRL_REG1, 0x27 ); + if( _status != 0 ) { + return; + } + // ... And on magnetometer + this->magRegisterWrite( MAG_MR_REG, 0x00 ); +} + +// ------------------------------------------- +int LSM303::accRegisterRead( int reg ) { + _bytes[0] = reg & 0xff; + _status = _i2c.write( ACC_ADDRESS + _SA0Pad, _bytes, 1 ); + if( _status == 0 ) { + _status = _i2c.read( ACC_ADDRESS + _SA0Pad + 1, _bytes, 1 ); + return( _bytes[0] ); + } + return( 0 ); +} + +// ------------------------------------------- +void LSM303::accRegisterWrite( int reg, char data ) { + _bytes[0] = reg & 0xff; + _bytes[1] = data & 0xff; + _status = _i2c.write( ACC_ADDRESS + _SA0Pad, _bytes, 2 ); +} + +// ------------------------------------------- +int LSM303::magRegisterRead( int reg ) { + _bytes[0] = reg & 0xff; + _status = _i2c.write( MAG_ADDRESS, _bytes, 1 ); + if( _status == 0 ) { + _status = _i2c.read( MAG_ADDRESS + 1, _bytes, 1 ); + return( _bytes[0] ); + } + return( 0 ); +} + +// ------------------------------------------- +void LSM303::magRegisterWrite( int reg, char data ) { + _bytes[0] = reg & 0xff; + _bytes[1] = data & 0xff; + _status = _i2c.write( MAG_ADDRESS, _bytes, 2 ); +} + + +// ------------------------------------------- +std::vector<short> LSM303::accRead( void ) { + std::vector<short> acc( 3, 0 ); + _bytes[0] = ACC_OUT_X_L | (1<<7); + _status = _i2c.write( ACC_ADDRESS + _SA0Pad, _bytes, 1 ); + if( _status == 0 ) { + _status = _i2c.read( ACC_ADDRESS + _SA0Pad + 1, _bytes, 6 ); + if( _status == 0 ) { + for( int i=0; i<3; i++ ) { + acc[i] = ( short( _bytes[2*i] ) | short(_bytes[2*i+1]) << 8 ); + } + } + } + return( acc ); +} + +// ------------------------------------------- +std::vector<float> LSM303::acceleration( void ) { + + const float cal[3][2] = { { 16291.5, -16245.4 }, { 16819.0, -16253.0 }, { 16994.8, -15525.6 } }; + + std::vector<float> acc( 3, 0 ); + int fs = ( this->accRegisterRead( ACC_CTRL_REG4 ) >> 4 ) & 0x3; + std::vector<short> a = this->accRead(); + if( _status == 0 ) { + for( int i=0; i<3; i++ ) { + acc[i] = acc[i] * ( (cal[i][0] - cal[i][1]) / 32768. ) + (cal[i][0]+cal[i][1])/2.; + acc[i] = float( a[i] ) * pow(2.,(fs+1)) / 32768.; + } + } + return( acc ); +} + +// ------------------------------------------- +std::vector<short> LSM303::magRead( void ) { + std::vector<short> mag( 3, 0 ); + _bytes[0] = MAG_OUT_X_H; + _status = _i2c.write( MAG_ADDRESS, _bytes, 1 ); + if( _status == 0 ) { + _status = _i2c.read( MAG_ADDRESS + 1, _bytes, 6 ); + if( _status == 0 ) { + mag[0] = short( _bytes[0] << 8 ) | short( _bytes[1] ); + mag[1] = short( _bytes[4] << 8 ) | short( _bytes[5] ); + mag[2] = short( _bytes[2] << 8 ) | short( _bytes[3] ); + } + } + return( mag ); +} + +// ------------------------------------------- +std::vector<float> LSM303::magneticField( void ) { + + float gainxy[] = { 1100., 855., 670., 450., 400., 330., 230. }; + float gainz[] = { 980., 760., 600., 400., 355., 295., 205. }; + + std::vector<float> mag( 3, 0 ); + int gn = ( this->magRegisterRead( MAG_CRB_REG ) >> 5 ) & 0x7; + std::vector<short> m = this->magRead(); + if( _status == 0 ) { + mag[0] = float( m[0] ) / gainxy[gn-1]; + mag[1] = float( m[1] ) / gainxy[gn-1]; + mag[2] = float( m[2] ) / gainz[gn-1]; + } + return( mag ); +} \ No newline at end of file