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V001. 2017_11_30 10:21 Working code from Tuesday's lab session.
Fork of 2017_11_28_ELEC347_Coursework by
DSP Coursework ELEC347 2017-2018 Group members: Matthew Thewsey, Thomas Morris, Samuel Waggett, Christopher Hills .
main.cpp
- Committer:
- thomasmorris
- Date:
- 2017-12-02
- Revision:
- 11:7efb6e4759cc
- Parent:
- 10:3495fff88da7
- Child:
- 12:d522a7a061d6
File content as of revision 11:7efb6e4759cc:
#include "mbed.h" #include "rtos.h" #include "Filter.hpp" unsigned short ADC_DATA; //Init values for difference equation //MBED Class Instances follows DigitalOut SampLED(LED1); //Digital Output (GREEN LED is PB_3, D13 You can use an Oscilloscope on This pin to confirm sample rate) //Analog Inputs AnalogIn QDEF(PA_7); // Q Factor AnalogIn BDEF(PA_6); // Boost Level AnalogIn FDEF(PA_5); //Centre Frequency AnalogIn Ain(PA_1); //Analog Input (Signal Input 0 to +3 Volts) AnalogOut Aout(PA_4); //Analog Output (Signal Input 0 to +3 Volts) //Declare Tickers Ticker sample_timer; //Declare Threads Thread t1; Thread t2; //Declare Ticker Rates float sample_rate = (1.0/35000); //Rate of sampling float coeff_rate = (1.0 / 20); //Rate of updating coefficients //Initial Input Value float input = 0.0; //Declare Filter FILTER BP_filter(48000,10000,-16,2); //Create object of type Filter(Fs,Fo,Boost,Q) //Declare Variables float Fo = 1; float Boost = 0; float Q = 1; //Declare Temporary Coefficient Values float Fo_Current; float Boost_Current; float Q_Current; //Forward Declarations void sampler(void); void coeff_update(void); int main() { t2.start(sampler);//Start the Sampler timed interrupt t1.start(coeff_update);//Update the coeffiecients of the filter while(1) { } } void coeff_update(void) { while(1){ Fo_Current = FDEF * 22000 + 10; if (abs(Fo_Current - BP_filter.Get_Fo()) > 50) //If Centre Frequency has changed significantly { BP_filter.Update_Fo(Fo_Current); //Update Centre Frequency } Boost_Current = BDEF * 100 - 50; if (abs(Boost_Current - BP_filter.Get_Boost()) > 2) //If Boost has changed significantly { BP_filter.Update_Boost(Boost_Current); //Update Boost } Q_Current = QDEF * 49 + 1; if (abs(Q_Current - BP_filter.Get_Q()) > 2) //If Q has changed significantly { BP_filter.Update_Q(Q_Current); //Update Q } BP_filter.Define_Filter(); //Calculate the coefficients //BP_filter.Print_Filter(); //Print the ceofficients printf("Q = %d \t Boost = %f \t Fo = %d\n\r", BP_filter.Get_Q(), BP_filter.Get_Boost(), BP_filter.Get_Fo()); Thread::wait(1000);//Sleep the thread for 1 second then re runs the coefficient calculation } } void sampler(void) { while(1) { SampLED = 1; //LED Indicates start of sampling input = Ain; BP_filter.setvalue(input); //Input ADC. N.B. ADC in MBED is 0.0 to 1.0 float!!!!!! Aout = BP_filter.getvalue(); SampLED = 0; //LED Indicates end of sampling Thread::wait(sample_rate/1000);//Look at this } }