Revision 1:a1d998b362e9, committed 2014-11-03

Comitter:

akashvibhute

Date:

Mon Nov 03 06:57:18 2014 +0000

Parent:

0:6b905abf1374

Commit message:

First commit, working program

Changed in this revision

--- a/TextLCD.lib	Mon Mar 31 19:09:14 2014 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +0,0 @@
-http://mbed.org/users/wim/code/TextLCD/#e0da005a777f

--- a/main.cpp	Mon Mar 31 19:09:14 2014 +0000
+++ b/main.cpp	Mon Nov 03 06:57:18 2014 +0000
@@ -1,24 +1,38 @@
 #include "mbed.h"
 #include "ADXL345.h"
-#include "TextLCD.h"
 
 ADXL345 accelerometer(p5, p6, p7, p8); // (SDA, SDO, SCL, CS);
 Serial pc(USBTX, USBRX); //For raw data
-TextLCD lcd(p15, p16, p17, p18, p19, p20, TextLCD::LCD16x2); // rs, e, d4-d7
+
+int readings[3] = {0, 0, 0};
+float mag_lsb;
+
+float x,y,z,mag_g;
+float acc_readings[6][3];
+float calc_offsets[3];
+const float g=9.80665;
+const float g_mm=g*1000;
+const float acc_res_mg=3.9063; //acc resolution mg/LSB
 
-float x,y,z;
+int8_t offset2_8bit_int[3]={0,0,0};
+char offset2_8bit_char[3];
+
+float mg_offsets[3]={0.0,0.0,0.0}; //fine offsets in mg's which cannot be corrected by adxl
+
+void acc_read();
+void display_acc();
+void acc_store_offsets();   
+int sign(float input); 
+void display_fine_acc();
 
 
 int main()
 {
-
-    int readings[3] = {0, 0, 0};
-
-    lcd.cls();
-    lcd.printf("Starting ADXL345 test...\n");
-    lcd.printf("Device ID is: 0x%02x\n", accelerometer.getDevId());
-        pc.printf("Starting ADXL345 test...\n");
-        pc.printf("Device ID is: 0x%02x\n", accelerometer.getDevId());
+    pc.baud(921600); //set baud rate for USB serial to 921600bps
+    
+    pc.printf("Starting ADXL345 test...\n");
+    pc.printf("Device ID is: 0x%02x\n", accelerometer.getDevId());
+        
 
     //Go into standby mode to configure the device.
     accelerometer.setPowerControl(0x00);
@@ -29,28 +43,298 @@
     //3.2kHz data rate.
     accelerometer.setDataRate(ADXL345_3200HZ);
 
+    pc.printf("Axes offsets: ");
+    pc.printf("X: %d \t",accelerometer.getOffset(0x00));
+    pc.printf("Y: %d \t",accelerometer.getOffset(0x01));
+    pc.printf("Z: %d \n",accelerometer.getOffset(0x02));
+
     //Measurement mode.
     accelerometer.setPowerControl(0x08);
-
-    while (1) {
+    
+    pc.printf("Current IMU reading: \n");
+    acc_read();
+    display_acc();
+    
+    pc.printf("\nTo Calculate new offsets IMU needs to be re-oriented 12 times,\n Send 'R' when ready...\n\n");
+    while(pc.getc() != 'R') {}
+    
+    pc.printf("Resetting current offsets... \n");
+    acc_store_offsets();
+    
+    {
+        pc.printf("Okay, ready for first coarse reading set,\n Put IMU with +Z pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1);
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        acc_readings[4][0]+=x;
+        acc_readings[4][1]+=y;
+        acc_readings[4][2]+=z;
+        }  
+        //display_acc();
+        pc.printf("\n");
+    
+        pc.printf("Put IMU with -Z pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1);
+        acc_read();
+        acc_readings[5][0]+=x;
+        acc_readings[5][1]+=y;
+        acc_readings[5][2]+=z;
+        }
+        //display_acc();
+        pc.printf("\n");
+    
+        
+        pc.printf("Put IMU with +Y pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1);
+        acc_read();
+        acc_readings[2][0]+=x;
+        acc_readings[2][1]+=y;
+        acc_readings[2][2]+=z;
+        }
+        //display_acc();
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with -Y pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1);
+        acc_read();
+        acc_readings[3][0]+=x;
+        acc_readings[3][1]+=y;
+        acc_readings[3][2]+=z;
+        }
+        //display_acc();
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with +X pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1);
+        acc_read();
+        acc_readings[0][0]+=x;
+        acc_readings[0][1]+=y;
+        acc_readings[0][2]+=z;
+        }
+        //display_acc();
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with -X pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1);
+        acc_read();
+        acc_readings[1][0]+=x;
+        acc_readings[1][1]+=y;
+        acc_readings[1][2]+=z;
+        }
+        //display_acc();
+        pc.printf("\n");
+    }
+    
+     calc_offsets[0] = (acc_readings[0][0] - acc_readings[1][0])/(10*2*acc_res_mg) - 256;
+     calc_offsets[1] = (acc_readings[2][1] - acc_readings[3][1])/(10*2*acc_res_mg) - 256;
+     calc_offsets[2] = (acc_readings[4][2] - acc_readings[5][2])/(10*2*acc_res_mg) - 256;
+     
+    calc_offsets[0] = calc_offsets[0]/4; //convert to 8 bit scale 15.6 mg/LSB
+    calc_offsets[1] = calc_offsets[1]/4; //convert to 8 bit scale 15.6 mg/LSB
+    calc_offsets[2] = calc_offsets[2]/4; //convert to 8 bit scale 15.6 mg/LSB
+    
+    pc.printf("Coarse calibration complete, offsets in 8bit scale (15.6mg/LSB) are: \t");
+    pc.printf("X: %.1f, Y: %.1f, Z: %.1f", calc_offsets[0], calc_offsets[1], calc_offsets[2]);
 
-        wait(0.1); //Intaval
-
-        accelerometer.getOutput(readings);
 
-        x=(int16_t)readings[0];
-        x=x*4e-3;
-        y=(int16_t)readings[1];
-        y=y*4e-3;
-        z=(int16_t)readings[2];
-        z=z*4e-3;
+    pc.printf("\n Apply offsets to ADXL345? Press Y to continue... \n");
+    while(pc.getc() != 'Y') {}
+    acc_store_offsets();    
+    pc.printf("\n Done! ADXL 345 is now calibrated!!!\n\n New offsets are: \n");
+        pc.printf("X: %d \t",accelerometer.getOffset(0x00));
+        pc.printf("Y: %d \t",accelerometer.getOffset(0x01));
+        pc.printf("Z: %d \n",accelerometer.getOffset(0x02));
+    pc.printf("\n");
+    wait(1);
+    
+    
+    {
+        float mg_offsets_x[2]={0,0};
+        float mg_offsets_y[2]={0,0};
+        float mg_offsets_z[2]={0,0};
+        
+        pc.printf("Ready for fine reading set,\n Put IMU with +Z pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1);
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        mg_offsets_z[0]+=z;
+        }
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with -Z pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        mg_offsets_z[1]+=z;
+        }
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with +Y pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        mg_offsets_y[0]+=y;
+        }
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with -Y pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        mg_offsets_y[1]+=y;
+        }
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with +X pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        mg_offsets_x[0]+=x;
+        }
+        pc.printf("\n");
+        
+        pc.printf("Put IMU with -X pointing up, then press 'R' when ready \n");
+        while(pc.getc() != 'R') {}
+        wait(0.1); 
+        for(int n=0; n<10; n++)
+        {
+        wait(0.1); 
+        acc_read();
+        mg_offsets_x[1]+=x;
+        }
+        pc.printf("\n");
+        
+        mg_offsets[0] = ((mg_offsets_x[0]/10 - 1000) + (1000 + mg_offsets_x[1]/10))/2;
+        mg_offsets[1] = ((mg_offsets_y[0]/10 - 1000) + (1000 + mg_offsets_y[1]/10))/2;
+        mg_offsets[2] = ((mg_offsets_z[0]/10 - 1000) + (1000 + mg_offsets_z[1]/10))/2;
+            
+        pc.printf("Fine calibration complete, offsets in mg are: \t");
+            pc.printf("X: %f \t",mg_offsets[0]);
+            pc.printf("Y: %f \t",mg_offsets[1]);
+            pc.printf("Z: %f \n",mg_offsets[2]);
+    }
+    
+    wait(5);
+    
+    while(1)
+    {
+        wait(0.25);
+        pc.printf("\nCurrent IMU reading:\n");
+        acc_read();
+        display_fine_acc();
+    }
+}
 
-        //13-bit, sign extended values.
-        lcd.cls();
-        lcd.printf("%.1f, %.1f, %.1f\n", x,y,z); //Convertet to G
-        lcd.printf(" X    Y    Z  ");
-            pc.printf("%i, %i, %i\n\r", (int16_t)readings[0], (int16_t)readings[1], (int16_t)readings[2]); //Raw data
+void acc_read()
+{
+    accelerometer.getOutput(readings);
+
+    x=(int16_t)readings[0] * acc_res_mg;
+    y=(int16_t)readings[1] * acc_res_mg;
+    z=(int16_t)readings[2] * acc_res_mg;
+        
+    mag_g = sqrt(pow(x,2)+pow(y,2)+pow(z,2));
+    mag_lsb = mag_g/acc_res_mg;
+}
+
+void display_acc()
+{
+    pc.printf("Raw: %i, %i, %i : %.1f\n", (int16_t)readings[0], (int16_t)readings[1], (int16_t)readings[2], mag_lsb); //Raw data
+    pc.printf("mG's: %.3f, %.3f, %.3f : %.4f\n", x, y, z, mag_g); //In G's data
+}
+
+void display_fine_acc()
+{
+    x -= mg_offsets[0];
+    y -= mg_offsets[1];
+    z -= mg_offsets[2];
+    
+    readings[0] -= (int16_t) (mg_offsets[0]/acc_res_mg);
+    readings[1] -= (int16_t) (mg_offsets[1]/acc_res_mg);
+    readings[2] -= (int16_t) (mg_offsets[2]/acc_res_mg);
+    
+    mag_g = sqrt(pow(x,2)+pow(y,2)+pow(z,2));
+    mag_lsb = mag_g/acc_res_mg;
+    
+    pc.printf("Raw: %i, %i, %i : %.1f\n", (int16_t)readings[0], (int16_t)readings[1], (int16_t)readings[2], mag_lsb); //Raw data
+    pc.printf("mG's: %.3f, %.3f, %.3f : %.4f\n", x, y, z, mag_g); //In G's data
+    pc.printf("Fine offset in mG's: %.3f, %.3f, %.3f\n", mg_offsets[0], mg_offsets[1], mg_offsets[2]); //In G's data
+}
 
+void acc_store_offsets()
+{
+    for(int v=0; v<=2; v++)
+    {
+        offset2_8bit_int[v] = (int8_t) calc_offsets[v];
+        if(abs(calc_offsets[v] - offset2_8bit_int[v]) >= 0.5)
+            offset2_8bit_int[v] += (int8_t) sign(calc_offsets[v]);
+        
+        offset2_8bit_int[v] = ~offset2_8bit_int[v];
+        offset2_8bit_int[v] += 1;
+        
+        offset2_8bit_char[v] = offset2_8bit_int[v];
     }
+    
+        //Go into standby mode to configure the device.
+        accelerometer.setPowerControl(0x00);
+    
+        accelerometer.setOffset(0x00, offset2_8bit_char[0]);
+        wait(0.1); //wait a bit
+        
+        accelerometer.setOffset(0x01, offset2_8bit_char[1]);
+        wait(0.1); //wait a bit
+        
+        accelerometer.setOffset(0x02, offset2_8bit_char[2]);
+        wait(0.1); //wait a bit
+        
+        //Measurement mode.
+        accelerometer.setPowerControl(0x08);
+}
 
-}
\ No newline at end of file
+int sign(float input)
+{
+    if (input<0)
+        return -1;
+    else if(input>0)
+        return 1;
+    else
+        return 0;
+}