ADXL345_I2C.cpp

00001 /**
00002  * @author Peter Swanson
00003  * A personal note from me: Jesus Christ has changed my life so much it blows my mind. I say this because
00004  *                  today, religion is thought of as something that you do or believe and has about as
00005  *                  little impact on a person as their political stance. But for me, God gives me daily
00006  *                  strength and has filled my life with the satisfaction that I could never find in any
00007  *                  of the other things that I once looked for it in. 
00008  * If your interested, heres verse that changed my life:
00009  *      Rom 8:1-3: "Therefore, there is now no condemnation for those who are in Christ Jesus,
00010  *                  because through Christ Jesus, the law of the Spirit who gives life has set
00011  *                  me free from the law of sin (which brings...) and death. For what the law 
00012  *                  was powerless to do in that it was weakened by the flesh, God did by sending
00013  *                  His own Son in the likeness of sinful flesh to be a sin offering. And so He
00014  *                  condemned sin in the flesh in order that the righteous requirements of the 
00015  *                  (God's) law might be fully met in us, who live not according to the flesh
00016  *                  but according to the Spirit."
00017  *
00018  * @section LICENSE
00019  *
00020  * Permission is hereby granted, free of charge, to any person obtaining a copy
00021  * of this software and associated documentation files (the "Software"), to deal
00022  * in the Software without restriction, including without limitation the rights
00023  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00024  * copies of the Software, and to permit persons to whom the Software is
00025  * furnished to do so, subject to the following conditions:
00026  *
00027  * The above copyright notice and this permission notice shall be included in
00028  * all copies or substantial portions of the Software.
00029  *
00030  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00031  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00032  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00033  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00034  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00035  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00036  * THE SOFTWARE.
00037  *
00038  * @section DESCRIPTION
00039  *
00040  * ADXL345, triple axis, I2C interface, accelerometer.
00041  *
00042  * Datasheet:
00043  *
00044  * http://www.analog.com/static/imported-files/data_sheets/ADXL345.pdf
00045  */  
00046  
00047 /**
00048  * Includes
00049  */
00050 #include "ADXL345_I2C.h"
00051 
00052 //#include "mbed.h"
00053 
00054 ADXL345_I2C::ADXL345_I2C(PinName sda, PinName scl) : i2c_(sda, scl) {
00055 
00056     //400kHz, allowing us to use the fastest data rates.
00057     i2c_.frequency(400000);   
00058 // initialize the BW data rate
00059     char tx[2];
00060     tx[0] = ADXL345_BW_RATE_REG;
00061     tx[1] = ADXL345_1600HZ; //value greater than or equal to 0x0A is written into the rate bits (Bit D3 through Bit D0) in the BW_RATE register 
00062  i2c_.write( ADXL345_I2C_WRITE , tx, 2);  
00063 
00064 //Data format (for +-16g) - This is done by setting Bit D3 of the DATA_FORMAT register (Address 0x31) and writing a value of 0x03 to the range bits (Bit D1 and Bit D0) of the DATA_FORMAT register (Address 0x31).
00065    
00066  char rx[2];
00067     rx[0] = ADXL345_DATA_FORMAT_REG;
00068     rx[1] = 0x0B; 
00069      // full res and +_16g
00070  i2c_.write( ADXL345_I2C_WRITE , rx, 2); 
00071  
00072  // Set Offset  - programmed into the OFSX, OFSY, and OFXZ registers, respectively, as 0xFD, 0x03 and 0xFE.
00073   char x[2];
00074     x[0] = ADXL345_OFSX_REG ;
00075     x[1] = 0xFD; 
00076  i2c_.write( ADXL345_I2C_WRITE , x, 2);
00077   char y[2];
00078     y[0] = ADXL345_OFSY_REG ;
00079     y[1] = 0x03; 
00080  i2c_.write( ADXL345_I2C_WRITE , y, 2);
00081  char z[2];
00082     z[0] = ADXL345_OFSZ_REG ;
00083     z[1] = 0xFE; 
00084  i2c_.write( ADXL345_I2C_WRITE , z, 2);
00085 }
00086 
00087 
00088 char ADXL345_I2C::SingleByteRead(char address){   
00089    char tx = address;
00090    char output; 
00091     i2c_.write( ADXL345_I2C_WRITE , &tx, 1);  //tell it what you want to read
00092     i2c_.read( ADXL345_I2C_READ , &output, 1);    //tell it where to store the data
00093     return output;
00094   
00095 }
00096 
00097 
00098 /*
00099 ***info on the i2c_.write***
00100 address     8-bit I2C slave address [ addr | 0 ]
00101 data        Pointer to the byte-array data to send
00102 length        Number of bytes to send
00103 repeated    Repeated start, true - do not send stop at end
00104 returns     0 on success (ack), or non-0 on failure (nack)
00105 */
00106 
00107 int ADXL345_I2C::SingleByteWrite(char address, char data){ 
00108    int ack = 0;
00109    char tx[2];
00110    tx[0] = address;
00111    tx[1] = data;
00112    return   ack | i2c_.write( ADXL345_I2C_WRITE , tx, 2);   
00113 }
00114 
00115 
00116 
00117 void ADXL345_I2C::multiByteRead(char address, char* output, int size) {
00118     i2c_.write( ADXL345_I2C_WRITE, &address, 1);  //tell it where to read from
00119     i2c_.read( ADXL345_I2C_READ , output, size);      //tell it where to store the data read
00120 }
00121 
00122 
00123 int ADXL345_I2C::multiByteWrite(char address, char* ptr_data, int size) {
00124         int ack;
00125    
00126                ack = i2c_.write( ADXL345_I2C_WRITE, &address, 1);  //tell it where to write to
00127         return ack | i2c_.write( ADXL345_I2C_READ, ptr_data, size);  //tell it what data to write
00128                                     
00129 }
00130 
00131 
00132 void ADXL345_I2C::getOutput(int* readings){
00133     char buffer[6];    
00134     multiByteRead(ADXL345_DATAX0_REG, buffer, 6);
00135     
00136     readings[0] = (int)buffer[1] << 8 | (int)buffer[0];
00137     readings[1] = (int)buffer[3] << 8 | (int)buffer[2];
00138     readings[2] = (int)buffer[5] << 8 | (int)buffer[4];
00139 
00140 }
00141 
00142 
00143 
00144 char ADXL345_I2C::getDeviceID() {  
00145     return SingleByteRead(ADXL345_DEVID_REG);
00146     }
00147 //
00148 int ADXL345_I2C::setPowerMode(char mode) { 
00149 
00150     //Get the current register contents, so we don't clobber the rate value.
00151     char registerContents = (mode << 4) | SingleByteRead(ADXL345_BW_RATE_REG);
00152 
00153    return SingleByteWrite(ADXL345_BW_RATE_REG, registerContents);
00154 
00155 }
00156 
00157 char ADXL345_I2C::getPowerControl() {    
00158     return SingleByteRead(ADXL345_POWER_CTL_REG);
00159 }
00160 
00161 int ADXL345_I2C::setPowerControl(char settings) {    
00162     return SingleByteWrite(ADXL345_POWER_CTL_REG, settings);
00163 
00164 }
00165 
00166 
00167 
00168 char ADXL345_I2C::getDataFormatControl(void){
00169 
00170     return SingleByteRead(ADXL345_DATA_FORMAT_REG);
00171 }
00172 
00173 int ADXL345_I2C::setDataFormatControl(char settings){
00174 
00175    return SingleByteWrite(ADXL345_DATA_FORMAT_REG, settings);
00176     
00177 }
00178 
00179 int ADXL345_I2C::setDataRate(char rate) {
00180 
00181     //Get the current register contents, so we don't clobber the power bit.
00182     char registerContents = SingleByteRead(ADXL345_BW_RATE_REG);
00183 
00184     registerContents &= 0x10;
00185     registerContents |= rate;
00186 
00187     return SingleByteWrite(ADXL345_BW_RATE_REG, registerContents);
00188 
00189 }
00190 
00191 
00192 char ADXL345_I2C::getOffset(char axis) {     
00193 
00194     char address = 0;
00195 
00196     if (axis == ADXL345_X) {
00197         address = ADXL345_OFSX_REG;
00198     } else if (axis == ADXL345_Y) {
00199         address = ADXL345_OFSY_REG;
00200     } else if (axis == ADXL345_Z) {
00201         address = ADXL345_OFSZ_REG;
00202     }
00203 
00204    return SingleByteRead(address);
00205 }
00206 
00207 int ADXL345_I2C::setOffset(char axis, char offset) {        
00208 
00209     char address = 0;
00210 
00211     if (axis == ADXL345_X) {
00212         address = ADXL345_OFSX_REG;
00213     } else if (axis == ADXL345_Y) {
00214         address = ADXL345_OFSY_REG;
00215     } else if (axis == ADXL345_Z) {
00216         address = ADXL345_OFSZ_REG;
00217     }
00218 
00219    return SingleByteWrite(address, offset);
00220 
00221 }
00222 
00223 
00224 char ADXL345_I2C::getFifoControl(void){
00225 
00226     return SingleByteRead(ADXL345_FIFO_CTL);
00227 
00228 }
00229 
00230 int ADXL345_I2C::setFifoControl(char settings){
00231    return SingleByteWrite(ADXL345_FIFO_STATUS, settings);
00232 
00233 }
00234 
00235 char ADXL345_I2C::getFifoStatus(void){
00236 
00237     return SingleByteRead(ADXL345_FIFO_STATUS);
00238 
00239 }
00240 
00241 
00242 
00243 char ADXL345_I2C::getTapThreshold(void) {
00244 
00245     return SingleByteRead(ADXL345_THRESH_TAP_REG);
00246 }
00247 
00248 int ADXL345_I2C::setTapThreshold(char threshold) {   
00249 
00250    return SingleByteWrite(ADXL345_THRESH_TAP_REG, threshold);
00251 
00252 }
00253 
00254 
00255 float ADXL345_I2C::getTapDuration(void) {     
00256 
00257     return (float)SingleByteRead(ADXL345_DUR_REG)*625;
00258 }
00259 
00260 int ADXL345_I2C::setTapDuration(short int duration_us) {
00261 
00262     short int tapDuration = duration_us / 625;
00263     char tapChar[2];
00264      tapChar[0] = (tapDuration & 0x00FF);
00265      tapChar[1] = (tapDuration >> 8) & 0x00FF;
00266     return multiByteWrite(ADXL345_DUR_REG, tapChar, 2);
00267 
00268 }
00269 
00270 float ADXL345_I2C::getTapLatency(void) {
00271 
00272     return (float)SingleByteRead(ADXL345_LATENT_REG)*1.25;
00273 }
00274 
00275 int ADXL345_I2C::setTapLatency(short int latency_ms) {
00276 
00277     latency_ms = latency_ms / 1.25;
00278     char latChar[2];
00279      latChar[0] = (latency_ms & 0x00FF);
00280      latChar[1] = (latency_ms << 8) & 0xFF00;
00281     return multiByteWrite(ADXL345_LATENT_REG, latChar, 2);
00282 
00283 }
00284 
00285 float ADXL345_I2C::getWindowTime(void) {
00286 
00287     return (float)SingleByteRead(ADXL345_WINDOW_REG)*1.25;
00288 }
00289 
00290 int ADXL345_I2C::setWindowTime(short int window_ms) {
00291 
00292     window_ms = window_ms / 1.25;
00293     char windowChar[2];
00294     windowChar[0] = (window_ms & 0x00FF);
00295     windowChar[1] = ((window_ms << 8) & 0xFF00);
00296    return multiByteWrite(ADXL345_WINDOW_REG, windowChar, 2);
00297 
00298 }
00299 
00300 char ADXL345_I2C::getActivityThreshold(void) {
00301 
00302     return SingleByteRead(ADXL345_THRESH_ACT_REG);
00303 }
00304 
00305 int ADXL345_I2C::setActivityThreshold(char threshold) {
00306     return SingleByteWrite(ADXL345_THRESH_ACT_REG, threshold);
00307 
00308 }
00309 
00310 char ADXL345_I2C::getInactivityThreshold(void) {
00311     return SingleByteRead(ADXL345_THRESH_INACT_REG);
00312        
00313 }
00314 
00315 //int FUNCTION(short int * ptr_Output)
00316 //short int FUNCTION ()
00317 
00318 int ADXL345_I2C::setInactivityThreshold(char threshold) {
00319     return SingleByteWrite(ADXL345_THRESH_INACT_REG, threshold);
00320 
00321 }
00322 
00323 char ADXL345_I2C::getTimeInactivity(void) {
00324 
00325     return SingleByteRead(ADXL345_TIME_INACT_REG);
00326 
00327 }
00328 
00329 int ADXL345_I2C::setTimeInactivity(char timeInactivity) {
00330     return SingleByteWrite(ADXL345_TIME_INACT_REG, timeInactivity);
00331 
00332 }
00333 
00334 char ADXL345_I2C::getActivityInactivityControl(void) {
00335 
00336     return SingleByteRead(ADXL345_ACT_INACT_CTL_REG);
00337 
00338 }
00339 
00340 int ADXL345_I2C::setActivityInactivityControl(char settings) {
00341     return SingleByteWrite(ADXL345_ACT_INACT_CTL_REG, settings);
00342     
00343 }
00344 
00345 char ADXL345_I2C::getFreefallThreshold(void) {
00346 
00347     return SingleByteRead(ADXL345_THRESH_FF_REG);
00348 
00349 }
00350 
00351 int ADXL345_I2C::setFreefallThreshold(char threshold) {
00352    return SingleByteWrite(ADXL345_THRESH_FF_REG, threshold);
00353 
00354 }
00355 
00356 char ADXL345_I2C::getFreefallTime(void) {
00357 
00358     return SingleByteRead(ADXL345_TIME_FF_REG)*5;
00359 
00360 }
00361 
00362 int ADXL345_I2C::setFreefallTime(short int freefallTime_ms) {
00363      freefallTime_ms = freefallTime_ms / 5;
00364      char fallChar[2];
00365      fallChar[0] = (freefallTime_ms & 0x00FF);
00366      fallChar[1] = (freefallTime_ms << 8) & 0xFF00;
00367     
00368     return multiByteWrite(ADXL345_TIME_FF_REG, fallChar, 2);
00369 
00370 }
00371 
00372 char ADXL345_I2C::getTapAxisControl(void) {
00373 
00374     return SingleByteRead(ADXL345_TAP_AXES_REG);
00375 
00376 }
00377 
00378 int ADXL345_I2C::setTapAxisControl(char settings) {
00379    return SingleByteWrite(ADXL345_TAP_AXES_REG, settings);
00380 
00381 }
00382 
00383 char ADXL345_I2C::getTapSource(void) {
00384 
00385     return SingleByteRead(ADXL345_ACT_TAP_STATUS_REG);
00386 
00387 }
00388 
00389 
00390 
00391 char ADXL345_I2C::getInterruptEnableControl(void) {
00392 
00393     return SingleByteRead(ADXL345_INT_ENABLE_REG);
00394 
00395 }
00396 
00397 int ADXL345_I2C::setInterruptEnableControl(char settings) {
00398    return SingleByteWrite(ADXL345_INT_ENABLE_REG, settings);
00399 
00400 }
00401 
00402 char ADXL345_I2C::getInterruptMappingControl(void) {
00403 
00404     return SingleByteRead(ADXL345_INT_MAP_REG);
00405 
00406 }
00407 
00408 int ADXL345_I2C::setInterruptMappingControl(char settings) {
00409     return SingleByteWrite(ADXL345_INT_MAP_REG, settings);
00410 
00411 }
00412 
00413 char ADXL345_I2C::getInterruptSource(void){
00414 
00415     return SingleByteRead(ADXL345_INT_SOURCE_REG);
00416 
00417 }
00418 
00419 
00420 
00421