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/*
 * @file adxl345unit.cpp
 * @author Tyler Weaver
 *
 * @section LICENSE
 *
 * 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.
 *
 * @section DESCRIPTION
 *
 * Unit test for the ADXL345 library.
 *
 * Reference:
 */

#include "adxl345unit.h"

ADXL345UNIT::ADXL345UNIT(I2C &i2c) : adxl345_(i2c), pc_(USBTX, USBRX), local_("local"), open_file_(LED1)
{
    pc_.baud(9600);
    open_file_ = 0;
    init();
}

void ADXL345UNIT::init()
{
    // place initilazaition code here
}

bool ADXL345UNIT::builtInSelfTest()
{
    bool test_pass[4] = {true,true,true,true};
    bool full_test = true;

    int st_off[3][100]; // {x,y,z}, self test off
    int st_off_avg[3];  // self test off average
    int st_on[3][100];  // {x,y,z}, self test off
    int st_on_avg[3];   // self test on average
    int delta[3];       // st_on - st_off

    const char axisK[3] = {'X','Y','Z'};
    const int resolutionsK[4] = {16,8,4,2};
    const char data_formatK[4] = {ADXL345_16G, ADXL345_8G, ADXL345_4G, (ADXL345_2G | ADXL345_FULL_RES)};
    const int delta_minK[4][3] = {{6,-67,10},{12,-135,19},{25,-270,38},{50,-540,75}}; // {{16g},{8g},{4g},{2g}} from datasheet
    const int delta_maxK[4][3] = {{67,-6,110},{135,-12,219},{270,-25,438},{540,-50,875}};

    Timer t; // for timming sample readings
    float start_time, elapsed_time;
    float period = 0.001; // period of sample rate

    for(int res = 0; res < 4; res++) {
        //print starting message
        pc_.printf("ADXL345: Starting Built In Self Test (%dg resolution)... \n\r", resolutionsK[res]);
        //wait 1.1ms
        wait(0.0011);
        //initial command sequence
        adxl345_.setDataFormatControl(data_formatK[res]); // 16g, 13bit mode
        adxl345_.setDataRate(ADXL345_100HZ); // 100Hz data rate
        adxl345_.setPowerMode(0); // high power
        adxl345_.setPowerControl(0x08); // start measurement
        adxl345_.setInterruptEnableControl(0x80); // enable data_ready interupt (not needed?)
        //wait 1.1ms
        wait(0.0011);
        //take 100 data points and average (100Hz)
        for(int sample = 0; sample < 100; sample++) {
            start_time = t.read();

            adxl345_.getOutput(st_off[sample]);

            elapsed_time = t.read() - start_time;
            if(elapsed_time > period) {
                pc_.puts("Error: elapsed_time > period\n\r");
                return false;
            }
            wait(period - elapsed_time);
        }
        for(int axis = 0; axis < 3; axis++)
            st_off_avg[axis] = arr_avg(st_off[axis], 100); // average
            
        //activate self test
        adxl345_.setDataFormatControl(data_formatK[res] | ADXL345_SELF_TEST); // self test enabled
        //wait 1.1ms
        wait(0.0011);
        //take 100 data points and average (100Hz)
        for(int sample = 0; sample < 100; sample++) {
            start_time = t.read();

            adxl345_.getOutput(st_on[sample]);

            elapsed_time = t.read() - start_time;
            if(elapsed_time > period) {
                pc_.puts("Error: elapsed_time > period\n\r");
                return false;
            }
            wait(period - elapsed_time);
        }
        for(int axis = 0; axis < 3; axis++)
            st_on_avg[axis] = arr_avg(st_on[axis], 100); // average
        //inactivate self test
        adxl345_.setDataFormatControl(data_formatK[res]); // self test off
        //calculate self test delta(change) and compare to limits in data sheet
        //open file
        open_file_ = 1;
        FILE *fp = fopen("/local/ADXL_BIT.csv", "a"); // open append, or create
        fprintf(fp, "ADXL345 Built In Self-Test at %dg resolution.\r\nAxis,Min,Max,Actual,Pass\r\n", resolutionsK[res]);
        for(int axis = 0; axis < 3; axis++) {
            delta[axis] = st_on_avg[axis] - st_off_avg[axis];
            bool test = (delta[axis] > delta_minK[res][axis] && delta[axis] < delta_maxK[res][axis]);
            if(test == false)
                test_pass[res] = full_test = false;
            fprintf(fp, "%c,%4d,%4d,%4d,%s\r\n", axisK[axis],delta_minK[res][axis],delta_maxK[res][axis],delta[axis],(test)?"pass":"fail");
        }
        fprintf(fp, "Test Result: %s\r\n\r\n", (test_pass[res])?"pass":"fail");
        // close file
        fclose(fp);
        open_file_ = 0;
        pc_.printf("%s\r\n", (test_pass[res])?"pass":"fail");
    }
    //return result
    return full_test;
}

int ADXL345UNIT::arr_avg(int* arr,int length)
{
    double average;
    for(int i = 0; i < length; i++)
        average += static_cast<double>(arr[i]) / static_cast<double>(length);
    return static_cast<int>(average);
}