data_logger.cpp

00001 //An embedded server sending sensor data to a client side process running on a PC for logging and analysis
00002 //TODO: Add in error handling and timeouts to deal with dropped connections and compile flags for testing
00003 
00004 #include "data_logger.h"
00005 
00006 EthernetInterface eth; 
00007 NTPClient ntp;
00008 TimeInterface time_b;
00009 Timer t;
00010 time_t timestamp;                                                                                       //Built-in time class instance 
00011 TCPSocketServer server;
00012 TCPSocketConnection client;
00013 EventQueue queue1; 
00014 EventQueue queue2;
00015 Thread t1; 
00016 Thread t2;
00017 Mutex m;
00018 
00019 //setup
00020 DigitalOut led1(LED1);
00021 AnalogIn strainIn(A0);
00022 InterruptIn sig(p5);
00023 
00024 //RtosTimer Timer(send_payload,osTimerPeriodic); 
00025 
00026 // main() runs in its own thread in the OS
00027 // (note the calls to Thread::wait below for delays)
00028 
00029 int main(void) 
00030 {
00031     eth.init(); //Use DHCP
00032     eth.setName("DL-test");                             //set a hostname
00033     eth_cxn_status = eth.connect();                     //Attempt an ethernet connection and save the status, add retries here in the future
00034     if(eth_cxn_status == 0) {
00035               //Bring up the ethernet interface
00036         printf("Detected Ethernet connection, entering network logging mode \n Server IP Address is %s\n", eth.getIPAddress());
00037             server.bind(SERVER_PORT);
00038             server.listen();                                                                                          //Wait for the client to connect
00039             server.accept(client);
00040             printf("Connection from: %s\n", client.get_address());
00041             if (ntp.setTime("0.pool.ntp.org") == 0)                                                                  //If time retrieval is successful
00042             {
00043             printf("Set time successfully\r\n");
00044 
00045             }
00046             else
00047             {
00048             printf("Unable to set time, error\r\n");
00049             }
00050         }
00051     else {
00052          printf("Entering USB logging mode");
00053          }
00054     
00055     timestamp = time(NULL);
00056     queue1.call_every(RATE,&idle_report); 
00057     t1.start(callback(&queue1, &EventQueue::dispatch_forever));                                          //Start the thread for periodic basline value reporting   
00058     sig.rise(queue2.event(&cycle_time_isr_rise));                                                                     
00059     sig.fall(queue2.event(&cycle_time_isr_fall));
00060     t2.start(callback(&queue2, &EventQueue::dispatch_forever));                                           //Start the cycle time and peak value calculation thread
00061                                                                                            
00062 }
00063 
00064 void cycle_time_isr_rise(void) { 
00065     t.start();                                                                                            //Start the timer
00066     m.lock();                                                                                             //Lock the mutex to prevent the baseline reporting thread from writing to the application buffer
00067     /*for(i=0;i<1023;i++) {
00068         samples[i] = pressureIn.read();
00069         //add a mean and peak pressure calculation here and you may want to slow down the sample rate
00070         i++;       
00071         }*/
00072     //p_press =  pressIn.read();
00073     p_strain = strainCalc();                                                                               //Calculate strain while the machine is crushing
00074     }
00075 
00076 void cycle_time_isr_fall(void) {
00077     t.stop();                                                                                              //Stop the timer
00078     cycle_time = t.read();
00079     t.reset();                                                                                             //reset the timer
00080     if(eth_cxn_status == 0) {
00081         sprintf(appbuffer,"<payload><time>%s</time><cy_time>%f</cy_time><p_strain>%f</p_strain></payload>",time_b.ctime(&timestamp), cycle_time, p_strain);
00082     }
00083     else {
00084         printf("Cycle time is: %f \n Strain detected during cycle is: %f% \r", cycle_time, p_strain);
00085     }
00086     sprintf(appbuffer,"\0");                                                                                //Nullify the string
00087     m.unlock();                                                                                             //Unlock the mutex
00088     };
00089 
00090 void idle_report(void) {
00091     m.lock();                                                                                               //Attempt to lock the mutex here
00092     id_strain = strainCalc();                                                                               //Calculate strain while the machine is idle
00093     if (eth_cxn_status == 0) {                                                                              //Log data based on the available connection
00094         sprintf(appbuffer,"<payload><time>%s</time><id_strain>%f</id_strain></payload>",time_b.ctime(&timestamp), id_strain);
00095     }
00096     else {
00097         printf("Strain while machine is idle: %f%",id_strain );
00098     }
00099 
00100     sprintf(appbuffer,"\0");                                                                                //Nullify the buffer
00101     m.unlock();                                                                                             //Unlock the mutex
00102     }
00103     
00104 float strainCalc(void) {
00105     float deltaR = strainIn/CURRENT;                                                                        //Calculate Delta R
00106     float strain = (1/GAUGE_FACTOR)*(deltaR/NOMINAL_R);                                                     //Calculate strain, see equation reference in docs
00107     return strain;
00108     }
00109