The following is only part of my code. ADCINA4_Voltage_sum is the input anlogue to digital converter value of sinusoidal signal generated by signal generator. v0 is a variable of an implemented digital filter which is used to generate phase for a output sinusoidal signal on GPI06.
However oscilloscope shows that there is no output signal in GPI06 after few cycles (50Hz). i believe this problem is becuase digital filter is designed an coded in such way that value of variable v0 keeps increasing to wards infinity. however in this program v0 is a IQ math value _iq15 that cannot be more than definite value(65535.999969482). Thus I can only observe the frist few cycles.
How can I hold an infinitely progressing real time operation in a variable???
while(1)
{
ADCINA4_Voltage = (ADCINA4_Voltage_sum - 2047);//CENTRED SINE SIGNAL AND SCALE BY 0.95
ADCINB4_Voltage = (AdcResult.ADCRESULT1-2046)*0.95;
c1 = EPwm2Regs.TBCTR;
c2 = (c1 -1000)* 2.047;//triangle carrier centred at zero with amplitude +- 2046
in = _IQ(ADCINA4_Voltage);
div = _IQ(2048);
realin = _IQ(in/div);//realin = _IQ(in/div);//real part of ADC signal//commented temporarily
Z = _IQacos(realin);
imagin = _IQsin(Z);//imag part of input signal
realout = _IQcos(phiout[i]);//phiout initiallly zero updates at end of while 1 loop
imagout = _IQsin(phiout[i]);
v2= _IQ(v1);
v1= _IQ(v0);
ph1 = _IQatan2(imagin,realin);
ph2 = _IQatan2(imagout,realout);
pherr = _IQ(ph1-ph2);
v0 = _IQ(pherr + v1*2 - v2*1);
b0 = _IQ(0.027880390);
b1 = _IQ(0.000777695);
b2 = _IQ(-0.027102694);
phiout = _IQmpy(v0, b0);
phiout += _IQmpy(v1, b1);
phiout += _IQmpy(v2, b2);
scale = _IQ(1900);
}
Y = _IQmpy(realout, scale);
if(Y >= 0)
{
if (Y < c2)
{
GpioDataRegs.GPACLEAR.bit.GPIO6 = 1;
}
else
{
GpioDataRegs.GPASET.bit.GPIO6 = 1;
}
}
else if (Y < 0)
{
if (abs(Y) < abs(c2))
{
GpioDataRegs.GPASET.bit.GPIO6 = 1;
}
else
{
GpioDataRegs.GPACLEAR.bit.GPIO6 = 1;
}
}
}
}
