ITG3200.cpp

00001 /**
00002  * @author Aaron Berk
00003  *
00004  * @section LICENSE
00005  *
00006  * Copyright (c) 2010 ARM Limited
00007  *
00008  * Permission is hereby granted, free of charge, to any person obtaining a copy
00009  * of this software and associated documentation files (the "Software"), to deal
00010  * in the Software without restriction, including without limitation the rights
00011  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00012  * copies of the Software, and to permit persons to whom the Software is
00013  * furnished to do so, subject to the following conditions:
00014  *
00015  * The above copyright notice and this permission notice shall be included in
00016  * all copies or substantial portions of the Software.
00017  *
00018  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00019  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00020  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00021  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00022  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00023  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00024  * THE SOFTWARE.
00025  *
00026  * @section DESCRIPTION
00027  *
00028  * ITG-3200 triple axis, digital interface, gyroscope.
00029  *
00030  * Datasheet:
00031  *
00032  * http://invensense.com/mems/gyro/documents/PS-ITG-3200-00-01.4.pdf
00033  */
00034 
00035 /**
00036  * Includes
00037  */
00038 #include "ITG3200.h"
00039 
00040 ITG3200::ITG3200(PinName sda, PinName scl) : i2c_(sda, scl) {
00041 
00042     //400kHz, fast mode.
00043     i2c_.frequency(400000);
00044     
00045     //Set FS_SEL to 0x03 for proper operation.
00046     //See datasheet for details.
00047     char tx[2];
00048     tx[0] = DLPF_FS_REG;
00049     //FS_SEL bits sit in bits 4 and 3 of DLPF_FS register.
00050     tx[1] = 0x03 << 3;
00051     
00052     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
00053 
00054 }
00055 
00056 char ITG3200::getWhoAmI(void){
00057 
00058     //WhoAmI Register address.
00059     char tx = WHO_AM_I_REG;
00060     char rx;
00061     
00062     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00063     
00064     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00065     
00066     return rx;
00067 
00068 }
00069 
00070 void ITG3200::setWhoAmI(char address){
00071 
00072     char tx[2];
00073     tx[0] = WHO_AM_I_REG;
00074     tx[1] = address;
00075     
00076     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
00077 
00078 }
00079 
00080 char ITG3200::getSampleRateDivider(void){
00081 
00082     char tx = SMPLRT_DIV_REG;
00083     char rx;
00084     
00085     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00086     
00087     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00088 
00089     return rx;
00090 
00091 }
00092 
00093 void ITG3200::setSampleRateDivider(char divider){
00094 
00095     char tx[2];
00096     tx[0] = SMPLRT_DIV_REG;
00097     tx[1] = divider;
00098 
00099     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
00100 
00101 }
00102 
00103 int ITG3200::getInternalSampleRate(void){
00104 
00105     char tx = DLPF_FS_REG;
00106     char rx;
00107     
00108     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00109     
00110     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00111     
00112     //DLPF_CFG == 0 -> sample rate = 8kHz.
00113     if(rx == 0){
00114         return 8;
00115     } 
00116     //DLPF_CFG = 1..7 -> sample rate = 1kHz.
00117     else if(rx >= 1 && rx <= 7){
00118         return 1;
00119     }
00120     //DLPF_CFG = anything else -> something's wrong!
00121     else{
00122         return -1;
00123     }
00124     
00125 }
00126 
00127 void ITG3200::setLpBandwidth(char bandwidth){
00128 
00129     char tx[2];
00130     tx[0] = DLPF_FS_REG;
00131     //Bits 4,3 are required to be 0x03 for proper operation.
00132     tx[1] = bandwidth | (0x03 << 3);
00133     
00134     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
00135 
00136 }
00137 
00138 char ITG3200::getInterruptConfiguration(void){
00139 
00140     char tx = INT_CFG_REG;
00141     char rx;
00142     
00143     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00144     
00145     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00146     
00147     return rx;
00148 
00149 }
00150 
00151 void ITG3200::setInterruptConfiguration(char config){
00152 
00153     char tx[2];
00154     tx[0] = INT_CFG_REG;
00155     tx[1] = config;
00156     
00157     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
00158 
00159 }
00160 
00161 bool ITG3200::isPllReady(void){
00162 
00163     char tx = INT_STATUS;
00164     char rx;
00165     
00166     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00167     
00168     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00169     
00170     //ITG_RDY bit is bit 4 of INT_STATUS register.
00171     if(rx & 0x04){
00172         return true;
00173     }
00174     else{
00175         return false;
00176     }
00177     
00178 }
00179 
00180 bool ITG3200::isRawDataReady(void){
00181 
00182     char tx = INT_STATUS;
00183     char rx;
00184     
00185     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00186     
00187     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00188     
00189     //RAW_DATA_RDY bit is bit 1 of INT_STATUS register.
00190     if(rx & 0x01){
00191         return true;
00192     }
00193     else{
00194         return false;
00195     }
00196     
00197 }
00198 
00199 float ITG3200::getTemperature(void){
00200 
00201     char tx = TEMP_OUT_H_REG;
00202     char rx[2];
00203     
00204     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00205     
00206     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, rx, 2);
00207     
00208     int16_t temperature = ((int) rx[0] << 8) | ((int) rx[1]);
00209     //Offset = -35 degrees, 13200 counts. 280 counts/degrees C.
00210     return 35.0 + ((temperature + 13200)/280.0);
00211     
00212 }
00213 
00214 int ITG3200::getGyroX(void){
00215 
00216     char tx = GYRO_XOUT_H_REG;
00217     char rx[2];
00218     
00219     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00220     
00221     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, rx, 2);
00222     
00223     int16_t output = ((int) rx[0] << 8) | ((int) rx[1]);
00224 
00225     return output;
00226 
00227 }
00228 
00229 int ITG3200::getGyroY(void){
00230 
00231     char tx = GYRO_YOUT_H_REG;
00232     char rx[2];
00233     
00234     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00235     
00236     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, rx, 2);
00237     
00238     int16_t output = ((int) rx[0] << 8) | ((int) rx[1]);
00239 
00240     return output;
00241 
00242 }
00243 
00244 int ITG3200::getGyroZ(void){
00245 
00246     char tx = GYRO_ZOUT_H_REG;
00247     char rx[2];
00248     
00249     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00250     
00251     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, rx, 2);
00252     
00253     int16_t output = ((int) rx[0] << 8) | ((int) rx[1]);
00254 
00255     return output;
00256     
00257 }
00258 
00259 char ITG3200::getPowerManagement(void){
00260 
00261     char tx = PWR_MGM_REG;
00262     char rx;
00263     
00264     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, &tx, 1);
00265     
00266     i2c_.read((ITG3200_I2C_ADDRESS << 1) | 0x01, &rx, 1);
00267     
00268     return rx;
00269 
00270 }
00271 
00272 void ITG3200::setPowerManagement(char config){
00273 
00274     char tx[2];
00275     tx[0] = PWR_MGM_REG;
00276     tx[1] = config;
00277 
00278     i2c_.write((ITG3200_I2C_ADDRESS << 1) & 0xFE, tx, 2);
00279 
00280 }