main.cpp

00001 #include "mbed.h"
00002 #include "ADXL345.h"
00003  
00004 ADXL345 accelerometer(p5, p6, p7, p8); // MOSI, MISO, SCK, CS_bar
00005 Serial pc(USBTX, USBRX);
00006 // 11-bit extented values; 50 readings stored in an array.
00007        int data[50][3];
00008        int reading = 0;
00009 int main() {
00010     
00011     int readings[3] = {0, 0, 0};
00012 
00013     pc.printf("\nStarting ADXL345 test...\n");
00014     pc.printf("Device ID is: 0x%02x\n\r", accelerometer.getDevId());
00015     //Go into standby mode to configure the device.
00016     accelerometer.setPowerControl(0x00);
00017  
00018     //Full resolution, +/-4g, 4mg/LSB.
00019     accelerometer.setDataFormatControl(0x09);
00020     
00021     //3.2kHz data rate.
00022     accelerometer.setDataRate(ADXL345_3200HZ);
00023  
00024     //Measurement mode.
00025     accelerometer.setPowerControl(0x08);   
00026  
00027       // Create timers
00028     Timer Write_time;
00029     Write_time.start(); 
00030 
00031         //Fill the data with values.
00032         for (int i=0; i<50; i++){
00033       // Create timers for counting sampling time, and hence sampling rate.
00034 //    Timer Sample_time;
00035 //    Sample_time.start();             
00036             accelerometer.getOutput(readings);
00037 //    Sample_time.stop();
00038 //    pc.printf("\nTime taken to take one sample= %f seconds\n\r",Sample_time.read());         
00039        
00040              for (int j=0; j<3; j++){           
00041             data[i][j] = readings[j];
00042             }
00043         }
00044         
00045     Write_time.stop();
00046     
00047     pc.printf("\nTime taken to write array= %f seconds\n\r",Write_time.read());         
00048         
00049       // Create timers
00050     Timer Read_time;
00051     Read_time.start();    
00052 // Write to PC
00053 for (int i=0; i<50; i++){     
00054                  reading++;
00055     //11-bit, sign extended values. 
00056        pc.printf("\nAx=%i, Ay=%i, Az=%i\n", (int16_t)data[i][0], (int16_t)data[i][1], (int16_t)data[i][2]);
00057         pc.printf ("reading %d\n\r", reading); 
00058     }
00059     Read_time.stop();  
00060         pc.printf("\nTime taken to read array= %f seconds\n\r",Read_time.read());         
00061   
00062 }
00063