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Add frequency error

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This commit is contained in:
F5OEO 2018-03-20 15:44:59 +00:00
parent 754c341387
commit 3969c35268
2 changed files with 13 additions and 1 deletions
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13
src/gpio.cpp
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@ -194,7 +194,7 @@ int clkgpio::ComputeBestLO(uint64_t Frequency,int Bandwidth)
best_divider=0;
for( divider=1;divider<4096;divider++)
{
if( Frequency*divider < 300e6 ) continue; // widest accepted frequency range
if( Frequency*divider < 600e6 ) continue; // widest accepted frequency range
if( Frequency*divider > 1500e6 ) break;
max_int_multiplier=((int)((double)(Frequency+Bandwidth)*divider*xtal_freq_recip));
@ -258,6 +258,17 @@ double clkgpio::GetFrequencyResolution()
return res;
}
double clkgpio::GetRealFrequency(double Frequency)
{
double FloatMult=((double)(CentralFrequency+Frequency)*PllFixDivider)/(double)(XOSC_FREQUENCY);
uint32_t freqctl = FloatMult*((double)(1<<20)) ;
int IntMultiply= freqctl>>20; // Need to be calculated to have a center frequency
freqctl&=0xFFFFF; // Fractionnal is 20bits
uint32_t FracMultiply=freqctl&0xFFFFF;
double RealFrequency=((double)IntMultiply+(FracMultiply/(double)(1<<20)))*(double)(XOSC_FREQUENCY)/PllFixDivider-(CentralFrequency+Frequency);
return RealFrequency;
}
int clkgpio::SetCenterFrequency(uint64_t Frequency,int Bandwidth)
{
CentralFrequency=Frequency;

1
src/gpio.h
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@ -162,6 +162,7 @@ class clkgpio:public gpio
void SetAdvancedPllMode(bool Advanced);
int SetCenterFrequency(uint64_t Frequency,int Bandwidth);
double GetFrequencyResolution();
double GetRealFrequency(double Frequency);
int ComputeBestLO(uint64_t Frequency,int Bandwidth);
int SetMasterMultFrac(uint32_t Mult,uint32_t Frac);
uint32_t GetMasterFrac(double Frequency);