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The transmitting code for JetX Engineering
Dependencies: MLX90614 mbed nRF24L01P
main.cpp
- Committer:
- FraserLaw23
- Date:
- 2017-03-23
- Revision:
- 0:42fb8bed86d5
File content as of revision 0:42fb8bed86d5:
#include "mbed.h" #include <math.h> #include "mlx90614.h" #include "nRF24L01P.h" Serial pc (USBTX, USBRX); InterruptIn rpm1 (p21); // initiate two rpm sensors 130/140 degrees was the best output for the rpm1 resistor InterruptIn rpm2 (p22); InterruptIn vibr (p23); // initiate vibration sensor AnalogIn press1 (p15); // initiate four pressure sensors AnalogIn press2 (p16); AnalogIn press5 (p17); AnalogIn press3 (p19); AnalogIn press4 (p18); AnalogIn air (p20); I2C i2c(p28,p27); // sda,scl MLX90614 temp1(&i2c, 0x5A<<1); // initiate using default address MLX90614 temp2(&i2c, 0x04<<1); // initiate using changed address Timer t_rpm1; // create two timers for rpm calculations Timer t_rpm2; Timer t_vibr; // create a timer for vibration calculations Ticker ticker; // create ticker to send data nRF24L01P wireless(p5, p6, p7, p8, p9, p10); // mosi, miso, sck, csn, ce, irq // viarables union rpm1_sensor{ float rpm_value; char bytes[4]; }r1; union rpm2_sensor{ float rpm_value; char bytes[4]; }r2; union vibr_sensor{ float vibr_value; char bytes[4]; }v; union press1_sensor{ float press_value; char bytes[4]; }p1; union press2_sensor{ float press_value; char bytes[4]; }p2; union press3_sensor{ float press_value; char bytes[4]; }p3; union press4_sensor{ float press_value; char bytes[4]; }p4; union air_sensor{ float air_value; char bytes[4]; }a; union temp1_sensor{ float temp_value; char bytes[4]; }t1; union temp2_sensor{ float temp_value; char bytes[4]; }t2; int rpm1_count = 0; int rpm2_count = 0; int rpm_sample_size = 6; //changed to 5 from 10 int vibr_count = 0; int vibr_sample_size = 10; int press_sample_size = 10; float press_sample1 = 0.0; float press_sample2 = 0.0; float press_sample3 = 0.0; float press_sample4 = 0.0; int air_sample_size = 10; float air_sample = 0.0; // voltage from a voltage divider with 5v input float air_volt_ref = 3.24; const int DATA_SIZE = 20; char data[DATA_SIZE]; char* data_pointers[DATA_SIZE] = {&r1.bytes[2], &r1.bytes[3], &r2.bytes[2], &r2.bytes[3], &v.bytes[2], &v.bytes[3], &p1.bytes[0], &p1.bytes[1], &p2.bytes[0], &p2.bytes[1], &p3.bytes[0], &p3.bytes[1], &p4.bytes[0], &p4.bytes[1], &a.bytes[2], &a.bytes[3], &t1.bytes[2], &t1.bytes[3], &t2.bytes[2], &t2.bytes[3]}; struct { float pressure0, pressure1, pressure2, pressure3; float temperature0, temperature1; float rpm0, rpm1; float vibration; float airflow; }ddata; // functions void setRpm1(){ if (rpm1_count == rpm_sample_size){ t_rpm1.stop(); // calculate frequency float time = t_rpm1.read(); float frequency = rpm1_count/time; // in Hz r1.rpm_value = frequency; rpm1_count = 0; t_rpm1.reset(); t_rpm1.start(); } else{ rpm1_count++; } } void resetRpm1(){ if(t_rpm1.read()>rpm_sample_size/2){ t_rpm1.reset(); rpm1_count = 0; r1.rpm_value = 0; } } void setRpm2(){ if (rpm2_count == rpm_sample_size){ t_rpm2.stop(); // calculate frequency float time = t_rpm2.read(); float frequency = rpm2_count/time; // in Hz r2.rpm_value = frequency; rpm2_count = 0; t_rpm2.reset(); t_rpm2.start(); } else{ rpm2_count++; } } void resetRpm2(){ if(t_rpm2.read()>rpm_sample_size/2){ t_rpm2.reset(); rpm1_count = 0; r2.rpm_value = 0; } } void setPressure(){ float press_sample1 = 0; float press_sample2 = 0; float press_sample3 = 0; float press_sample4 = 0; for (int i = 0; i < press_sample_size; i++){ press_sample1 += press1.read(); press_sample2 += press2.read(); press_sample3 += press3.read(); press_sample4 += press4.read(); wait(0.02); } float avgPr1 = press_sample1/press_sample_size; // Transfer Function from data sheet: //Vout = VS*(0.0018*P+0.04) ± Error // Where : // VS = 5.0 Vdc // Temperature = 0 to 85°C //pc.printf("avg press 1 = %0.2f\n", avgPr1); //float avg = avgPr1; avgPr1 *= 100; //avgPr1 = (((avgPr1+0.2) / 5.13) - 0.04) / 0.0018; //avgPr1 = ((avgPr1 / 5) - 0.04) / 0.0018; //pc.printf("avg press 1 = %0.2f\n", avgPr1); p1.press_value = avgPr1; // converts to integer float avgPr2 = press_sample2/press_sample_size; avgPr2 *= 100; //avgPr2 = (((avgPr2+1.0) / 4.6) - 0.04) / 0.0018; p2.press_value = avgPr2; float avgPr3 = press_sample3/press_sample_size; avgPr3 *= 100; // (((avgPr3+1.1) / 4.6) - 0.04) / 0.0018; p3.press_value = avgPr3; float avgPr4 = press_sample4/press_sample_size; avgPr4 *= 100; //(((avgPr4+1.0) / 4.6) - 0.04) / 0.0018; p4.press_value = avgPr4; } void setAirspeed(){ float air_sample = 0; for (int i = 0; i < air_sample_size; i++){ air_sample += air.read(); wait(0.02); } //pc.printf("analog read %f\n", air.read() ); float avgAir = air_sample/air_sample_size; // transfer function from datasheet //NOTE added comments //avgAir = (avgAir/air_volt_ref - 0.5) * 5; //pc.printf("pressure is %f\n", pressure); // END NOTE // Vout = Vs * (0.2 * P(kPa) + 0.5) +- 6.25% avgAir = avgAir / 3.3 * 5; float pressure = ((avgAir * air_volt_ref / 5) - 0.5f) * 1/0.2f; pressure *= 1000; //pc.printf("pressure is %f\r", pressure); // air speed (m/s) formula: speed_of_sound(in m/s)in room temp (20 degrees) * sqrt( ( (measured_pressure/pressure_at_sea_level + 1)^(2/7) -1) *5) float calc_power = pow((((avgAir) / 10132.5) + 1), 0.285714286); float calc_sqrt = 5 * (calc_power - 1); calc_sqrt = sqrt(calc_sqrt); float calc_airSpeed = 343.21 * calc_sqrt; //pc.printf("calc airspeed %f\n", calc_airSpeed); a.air_value = calc_airSpeed; } void setVibration(){ if (vibr_count == vibr_sample_size){ vibr.disable_irq(); t_vibr.stop(); // calculate frequency float time = t_vibr.read(); float frequency = vibr_count/time; // in Hz v.vibr_value = frequency; vibr_count = 0; t_vibr.reset(); t_vibr.start(); wait(0.025); vibr.enable_irq(); } else{ vibr_count++; vibr.disable_irq(); wait(0.025); vibr.enable_irq(); } } void resetVibration(){ if(t_vibr.read()>vibr_sample_size/2){ t_vibr.reset(); vibr_count = 0; v.vibr_value = 0; } } void synchronizeData(){ for (int i = 0; i<DATA_SIZE; i++){ data[i] = *data_pointers[i]; } } void pcHeader(){ // Display the (default) setup of the nRF24L01+ chip pc.printf( "nRF24L01+ Frequency : %d MHz\r\n", wireless.getRfFrequency() ); pc.printf( "nRF24L01+ Output power : %d dBm\r\n", wireless.getRfOutputPower() ); pc.printf( "nRF24L01+ Data Rate : %d kbps\r\n", wireless.getAirDataRate() ); pc.printf( "nRF24L01+ TX Address : 0x%010llX\r\n", wireless.getTxAddress() ); pc.printf( "nRF24L01+ RX Address : 0x%010llX\r\n\n", wireless.getRxAddress() ); } void pcDataOut(){ pc.printf("Temperature sensor 1 reading: %3.1f degrees celcius\n", t1.temp_value); pc.printf("Temperature sensor 2 reading: %3.1f degrees celcius\n", t2.temp_value); pc.printf("RPM sensor 1 reading: %.1f Hz, %d rpm\n", r1.rpm_value, (int) (r1.rpm_value*60 + 0.5)); pc.printf("RPM sensor 2 reading: %.1f Hz, %d rpm\n", r2.rpm_value, (int) (r2.rpm_value*60 + 0.5)); pc.printf("Vibration sensor reading: %.1f Hz, %d rpm\n", v.vibr_value, (int) (v.vibr_value*60 + 0.5)); pc.printf("Pressure Sensor 1 reading: %.2f kPa\n", p1.press_value); pc.printf("Pressure Sensor 2 reading: %.2f kPa\n", p2.press_value); pc.printf("Pressure Sensor 3 reading: %.2f kPa\n", p3.press_value); pc.printf("Pressure Sensor 4 reading: %.2f kPa\n\n", p4.press_value); pc.printf("Air Speed Sensor reading: %.2f m/s\n\n", a.air_value); // individual bytes to be sent in hex //pc.printf("%x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x, %x\n", //data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7], data[8], data[9], //data[10], data[11], data[12], data[13], data[14], data[15], data[16], data[17], data[18], data[19]); } int main() { //static_assert(sizeof(data) == 40, "unexpected strucure size"); wireless.powerUp(); t_rpm1.start(); t_rpm2.start(); t_vibr.start(); //pcHeader(); // print info on screen // wireless setup wireless.setTransferSize(DATA_SIZE); wireless.setReceiveMode(); wireless.enable(); // rpm1 sampling on rising edge rpm1.rise(&setRpm1); // rpm2 sampling on rising edge rpm2.rise(&setRpm2); // vibration ampling on rising edge vibr.rise(&setVibration); // sample pressure and airspeed every set interval ticker.attach(&setPressure, 0.7); ticker.attach(&setAirspeed, 0.7); while(1) { // reset to 0 if idle resetRpm1(); resetRpm2(); resetVibration(); temp1.getTemp(&t1.temp_value); temp2.getTemp(&t2.temp_value); setPressure(); synchronizeData(); wireless.write(NRF24L01P_PIPE_P0, data, sizeof data); // fill in the data and send //ddata = {0};+ //#define GUI #ifdef GUI memset(&ddata, 0, sizeof(ddata)); ddata.temperature0 = t1.temp_value; ddata.temperature1 = t2.temp_value; ddata.rpm0 = r1.rpm_value; ddata.rpm1 = r2.rpm_value; ddata.vibration = v.vibr_value; ddata.pressure0 = p1.press_value; ddata.pressure1 = p2.press_value; ddata.pressure2 = p3.press_value; ddata.pressure3 = p4.press_value; ddata.airflow = a.air_value; char *ptr = (char*)&ddata; size_t s = sizeof(ddata); pc.putc('s'); for (unsigned j = 0; j < s; ++j) { pc.putc(ptr[j]); } #else pcDataOut(); #endif wait(0.2); } }