main.cpp

00001 #include "mbed.h"
00002 #include "rtos.h"
00003 
00004 const int addr = 0x20;                     //slave address 
00005 I2C master (D14,D15);                      //configure pins p27,p28 as I2C master
00006 Serial pc (USBTX,USBRX);
00007 DigitalOut interrupt(D9);
00008 InterruptIn data_ready(D10);
00009 
00010 int reset;
00011 
00012 typedef struct
00013 {
00014     char data[35];          // To avoid dynamic memory allocation
00015     int length;
00016 }i2c_data;
00017 
00018 Mail<i2c_data,16> i2c_data_receive;
00019 Mail<i2c_data,16> i2c_data_send;
00020 
00021 Thread * ptr_t_i2c;
00022 void FUNC_I2C_MASTER_FSLAVE(char * data,int length)
00023 {
00024     //printf("press backspace for master to start \n\r");
00025     //while(1){
00026             //interrupt = 0;
00027       //  if(pc.getc()=='z'){
00028             wait(0.5);
00029             interrupt = 1;
00030             printf("\nMaster executed\n");
00031             
00032           
00033             bool ack0 =true; 
00034             bool loopvariable0 =true;
00035             //char *data =  new char;
00036             //*data = 'b';
00037            
00038            
00039             
00040              master.frequency(100000);                       //set clock frequency
00041              //master.start();
00042             /*while(write2slave)
00043             {  *writedata = pc.getc();
00044             wait(0.5);
00045               
00046                 printf("master clk freq setup and addressing slave\n\r");
00047                 master.start();                                 //initiating the data transfer
00048                 master_status_write = (bool) master.write(addr|0x00,writedata,1);
00049                 if(master_status_write==0)
00050                 {
00051                     printf("master has written %c to slave\n\r",*writedata);
00052                     write2slave=false;
00053                 }
00054                     
00055                     
00056              }*/
00057              
00058             while(ack0)
00059             {
00060                 //printf("2 master clk freq setup and addressing slave\n\r");
00061                 
00062                 master.start();                                 //initiating the data transfer
00063                 ack0 =  master.read(addr,data,length);
00064             }
00065             if(!ack0)
00066             {
00067                     printf("\n master has read %s from slave\n\r",data);
00068                     loopvariable0=false;
00069             }
00070                 //master.stop();
00071             
00072             //printf("done\n\r");
00073             //delete data;
00074             interrupt=0;
00075 }
00076             
00077 void T_I2C_MASTER_FSLAVE(void const *args)
00078 {
00079     char data_receive[35];
00080     while(1)
00081     {
00082         Thread::signal_wait(0x1);
00083         FUNC_I2C_MASTER_FSLAVE(data_receive,35);
00084         i2c_data * i2c_data_r = i2c_data_receive.alloc();
00085         strcpy(i2c_data_r->data , data_receive);
00086         i2c_data_r->length = 35;
00087         i2c_data_receive.put(i2c_data_r);
00088         printf("\n Data received from slave is %s\n\r",data_receive);
00089         i2c_data_receive.free(i2c_data_r);
00090     }
00091 }
00092 
00093 void FUNC_INT()
00094 {
00095   
00096    ptr_t_i2c->signal_set(0x1);
00097      
00098 }
00099 
00100 char writedata[35];
00101 bool write2slave;
00102 bool master_status_write;
00103 void FUNC_MASTER_WRITE()
00104 {   //wait(1);
00105     write2slave=true;
00106    
00107     interrupt = 1;
00108      
00109     char data[35];
00110     strcpy(data,"sakthi");
00111     strcat(data,"priya");
00112     i2c_data * i2c_data_s = i2c_data_send.alloc();
00113     strcpy(i2c_data_s->data ,data);
00114     i2c_data_s->length = 35;
00115     i2c_data_send.put(i2c_data_s); 
00116     master_status_write = true;
00117     
00118    // interrupt = 1; 
00119 
00120     osEvent evt = i2c_data_send.get();
00121             if (evt.status == osEventMail) 
00122             {
00123                 i2c_data *i2c_data_s = (i2c_data*)evt.value.p;
00124                 strcpy(writedata ,i2c_data_s -> data);
00125                 master.frequency(100000);                        //set clock frequency
00126                 while(write2slave)
00127                 {                
00128                 printf("master clk freq setup and addressing slave\n\r");
00129                 master.start();                                 //initiating the data transfer
00130                 master_status_write = (bool) master.write(addr|0x00,writedata,35);
00131                 if(master_status_write==0)
00132                     {
00133                     printf("master has written %s to slave\n\r",writedata);
00134                     write2slave=false;
00135                     }
00136                 i2c_data_send.free(i2c_data_s);
00137                 }
00138             }
00139             interrupt = 0;
00140 }
00141 
00142     
00143 
00144 int main()
00145 {   
00146     ptr_t_i2c = new Thread(T_I2C_MASTER_FSLAVE);
00147     data_ready.rise(&FUNC_INT);
00148     printf("\nstarted master\n"); 
00149     while(1)
00150     { Thread::wait(8000);
00151     //interrupt = 1;
00152       
00153       FUNC_MASTER_WRITE(); 
00154       //interrupt = 0; 
00155       ;
00156     }
00157 }