main.cpp

00001 #include "mbed.h"
00002 
00003 Serial pc(USBTX, USBRX);    // debugging
00004 
00005 DigitalOut enable(p26);    // enable pin
00006 I2C i2c(p28, p27);         // accelerometer
00007 
00008 const int address = 0x30;
00009 
00010 const int CTRL_REGB = 0x0D;
00011 const int CTRL_REGC = 0x0C;
00012 
00013 const int XOUT_H = 0x00;    //x
00014 const int XOUT_L = 0x01;
00015 
00016 const int YOUT_H = 0x02;    //y
00017 const int YOUT_L = 0x03;
00018 
00019 const int ZOUT_H = 0x04;    //z
00020 const int ZOUT_L = 0x05;
00021 
00022 
00023 //--------------- IC2 helper functions ---------------
00024 
00025 // write value into register regno, return success
00026 bool write_reg(int regno, int value) {
00027 
00028     char data[2] = {regno, value}; 
00029     
00030     return i2c.write(address, data, 2) == 0;
00031     
00032 }
00033 
00034 // read value from register regno, return success
00035 bool read_reg(int regno, int *value) {
00036 
00037     char data = regno; 
00038     
00039     if (i2c.write(address, &data, 1) == 0 && i2c.read(address, &data, 1) == 0){
00040         *value = data;
00041         return true;
00042     }
00043     return false;
00044     
00045 }
00046 
00047 // read complete value of X axis, return it or -1 on failure
00048 int read_x() {
00049 
00050     int low, high;
00051     
00052     if ( read_reg(XOUT_H, &high) && read_reg(XOUT_L, &low) )
00053         return high<<8 | low;
00054     else
00055         return -1;
00056 }
00057 
00058 // read complete value of Y axis, return it or -1 on failure
00059 int read_y() {
00060 
00061     int low, high;
00062     
00063     if ( read_reg(YOUT_H, &high) && read_reg(YOUT_L, &low) )
00064         return high<<8 | low;
00065     else
00066         return -1;
00067 }
00068 
00069 // read complete value of Z axis, return it or -1 on failure
00070 int read_z() {
00071 
00072     int low, high;
00073     
00074     if ( read_reg(ZOUT_H, &high) && read_reg(ZOUT_L, &low) )
00075         return high<<8 | low;
00076     else
00077         return -1;
00078 }
00079 
00080 void accData(){
00081 
00082     enable = 1;
00083     
00084     write_reg(CTRL_REGB, 0xC2);
00085     write_reg(CTRL_REGC, 0x00);
00086     
00087     for (int i = 0; i < 1000; i++){
00088     
00089         printf("%d,%d,%d \n", read_x(), read_y(), read_z());
00090 
00091         wait(0.05);
00092 
00093     }
00094     
00095     enable = 0;
00096 
00097 }
00098 
00099 void accLEDs(){
00100 
00101     DigitalOut x0(p20);    //red
00102     DigitalOut x1(p19);    //green
00103     DigitalOut x2(p16);    //green
00104     DigitalOut x3(p15);    //green
00105     DigitalOut x4(p13);    //green
00106     DigitalOut x5(p11);    //red
00107     
00108     enable = 1;
00109     
00110     write_reg(CTRL_REGB, 0xC2); //start
00111     write_reg(CTRL_REGC, 0x00);
00112     
00113     for (int i = 0; i < 1000; i++){
00114     
00115         double x = double (read_x() - 32768)/9000; //normalise to around 0g/1g
00116         double y = double (read_y() - 32768)/9000;
00117         double z = double (read_z() - 32768)/9000;
00118         
00119         //pc.printf("%.2f, %.2f, %.2f \n", x, y, z);
00120         //pc.printf("%.2f \n", x);
00121         
00122         x0 = 0; x1 = 0; x2 = 0; x3 = 0; x4 = 0; x5 = 0;
00123         
00124         int intx = (x+0.1)*5; //scale to an integer from 0 to 5
00125         
00126         pc.printf("%d \n", intx);
00127         
00128         switch (intx) {
00129         
00130             case 0:
00131                 x0 = 1;
00132                 break;
00133             case 1:
00134                 x1 = 1;
00135                 break;  
00136             case 2:
00137                 x2 = 1;
00138                 break;  
00139             case 3:
00140                 x3 = 1;
00141                 break;  
00142             case 4:
00143                 x4 = 1;
00144                 break;  
00145             case 5:
00146                 x5 = 1;
00147                 break;      
00148                 
00149             default: 
00150                 break;
00151         }
00152         
00153         wait(0.1);
00154         
00155     }
00156     
00157     x0 = 0; x1 = 0; x2 = 0; x3 = 0; x4 = 0; x5 = 0;
00158     
00159     enable = 0;
00160 
00161 }
00162 
00163 
00164 //-------------------- Main -------------------
00165 
00166 int main() {
00167     
00168     pc.printf("Program started\n");
00169     
00170     //accData();
00171     
00172     accLEDs();
00173     
00174     pc.printf("Program complete\n\n");
00175 }