kopia lustrzana https://github.com/sq8vps/vp-digi
9600 untested
sq8vps
rodzic
e4f659d9da
commit
bb6797b293
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@ -22,6 +22,7 @@ along with VP-Digi. If not, see <http://www.gnu.org/licenses/>.
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#define IS_UPPERCASE_ALPHANUMERIC(x) ((((x) >= '0') && ((x) <= '9')) || (((x) >= 'A') && ((x) <= 'Z')))
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#define IS_NUMBER(x) (((x) >= '0') && ((x) <= '9'))
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#define ABS(x) (((x) > 0) ? (x) : (-x))
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#define CRC32_INIT 0xFFFFFFFF
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@ -69,13 +69,13 @@ along with VP-Digi. If not, see <http://www.gnu.org/licenses/>.
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#define PLL300_LOCKED_TUNE 0.74f
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#define PLL300_NOT_LOCKED_TUNE 0.50f
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#define AGC9600_ATTACK 0.08f
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#define AGC9600_DECAY 0.0008f
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#define DAC_SINE_SIZE 32 //DAC sine table size
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#define PTT_ON GPIOB->BSRR = GPIO_BSRR_BS7
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#define PTT_OFF GPIOB->BSRR = GPIO_BSRR_BR7
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#define DCD_ON (GPIOC->BSRR = GPIO_BSRR_BR13)
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#define DCD_OFF (GPIOC->BSRR = GPIO_BSRR_BS13)
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struct ModemDemodConfig ModemConfig;
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@ -92,9 +92,9 @@ static float baudRate; //baudrate
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static uint8_t markStep; //mark timer step
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static uint8_t spaceStep; //space timer step
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static uint16_t baudRateStep; //baudrate timer step
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static int32_t coeffHiI[NMAX], coeffLoI[NMAX], coeffHiQ[NMAX], coeffLoQ[NMAX]; //correlator IQ coefficients
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static int16_t coeffHiI[NMAX], coeffLoI[NMAX], coeffHiQ[NMAX], coeffLoQ[NMAX]; //correlator IQ coefficients
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static uint8_t dcd = 0; //multiplexed DCD state from both demodulators
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static uint32_t lfsr = 0; //LFSR for 9600 Bd
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/**
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* @brief BPF filter with 2200 Hz tone 6 dB preemphasis (it actually attenuates 1200 Hz tone by 6 dB)
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@ -193,7 +193,7 @@ struct DemodState
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enum ModemPrefilter prefilter;
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struct Filter bpf;
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int32_t correlatorSamples[NMAX];
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int16_t correlatorSamples[NMAX];
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uint8_t correlatorSamplesIdx;
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struct Filter lpf;
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@ -214,6 +214,9 @@ struct DemodState
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int32_t dcdInc;
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int32_t dcdDec;
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float dcdAdjust;
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int16_t peak;
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int16_t valley;
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};
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static struct DemodState demodState[MODEM_MAX_DEMODULATOR_COUNT];
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@ -296,6 +299,15 @@ static void setDcd(uint8_t state)
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}
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}
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static inline uint8_t scramble(uint8_t in)
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{
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//G3RUH scrambling (x^17+x^12+1)
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uint8_t bit = ((lfsr & 0x10000) > 0) ^ ((lfsr & 0x800) > 0) ^ (in > 0);
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lfsr <<= 1;
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lfsr |= bit;
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return bit;
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}
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/**
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* @brief ISR for demodulator
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@ -343,18 +355,34 @@ void TIM1_UP_IRQHandler(void)
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{
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TIM1->SR &= ~TIM_SR_UIF;
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int32_t sample = 0;
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if(ModemConfig.modem == MODEM_9600)
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{
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if(ModemConfig.usePWM)
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sample = currentSymbol ? 90 : 0;
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else
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sample = currentSymbol ? 15 : 1;
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sample = filter(&demodState[0].lpf, sample);
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}
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else
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{
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sample = dacSine[dacSineIdx];
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dacSineIdx++;
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dacSineIdx &= (DAC_SINE_SIZE - 1);
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}
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if(ModemConfig.usePWM)
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{
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TIM4->CCR1 = dacSine[dacSineIdx];
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TIM4->CCR1 = sample;
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}
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else
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{
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GPIOB->ODR &= ~0xF000; //zero 4 oldest bits
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GPIOB->ODR |= (dacSine[dacSineIdx] << 12); //write sample to 4 oldest bits
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GPIOB->ODR |= (sample << 12); //write sample to 4 oldest bits
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}
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dacSineIdx++;
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dacSineIdx &= (DAC_SINE_SIZE - 1);
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}
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@ -381,10 +409,17 @@ void TIM3_IRQHandler(void)
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TIM1->CNT = 0;
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if(currentSymbol) //current symbol is space
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TIM1->ARR = spaceStep;
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else //mark
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TIM1->ARR = markStep;
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if(ModemConfig.modem == MODEM_9600)
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{
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currentSymbol = scramble(currentSymbol);
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}
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else
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{
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if(currentSymbol) //current symbol is space
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TIM1->ARR = spaceStep;
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else //mark
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TIM1->ARR = markStep;
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}
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}
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@ -400,34 +435,38 @@ static int32_t demodulate(int16_t sample, struct DemodState *dem)
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dem->RMSenergy += ((sample >> 1) * (sample >> 1)); //square the sample and add it to the sum
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dem->RMSsampleCount++; //increment number of samples
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if(dem->prefilter != PREFILTER_NONE) //filter is used
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if(ModemConfig.modem != MODEM_9600)
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{
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dem->correlatorSamples[dem->correlatorSamplesIdx++] = filter(&dem->bpf, sample);
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}
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else //no pre/deemphasis
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{
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dem->correlatorSamples[dem->correlatorSamplesIdx++] = sample;
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if(dem->prefilter != PREFILTER_NONE) //filter is used
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{
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dem->correlatorSamples[dem->correlatorSamplesIdx++] = filter(&dem->bpf, sample);
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}
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else //no pre/deemphasis
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{
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dem->correlatorSamples[dem->correlatorSamplesIdx++] = sample;
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}
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dem->correlatorSamplesIdx %= N;
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int32_t outLoI = 0, outLoQ = 0, outHiI = 0, outHiQ = 0; //output values after correlating
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for(uint8_t i = 0; i < N; i++)
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{
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int16_t t = dem->correlatorSamples[(dem->correlatorSamplesIdx + i) % N]; //read sample
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outLoI += t * coeffLoI[i]; //correlate sample
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outLoQ += t * coeffLoQ[i];
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outHiI += t * coeffHiI[i];
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outHiQ += t * coeffHiQ[i];
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}
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outHiI >>= 12;
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outHiQ >>= 12;
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outLoI >>= 12;
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outLoQ >>= 12;
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sample = ABS(outHiI) + ABS(outHiQ) - ABS(outLoI) - ABS(outLoQ);
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}
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dem->correlatorSamplesIdx %= N;
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int64_t outLoI = 0, outLoQ = 0, outHiI = 0, outHiQ = 0; //output values after correlating
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for(uint8_t i = 0; i < N; i++)
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{
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int32_t t = dem->correlatorSamples[(dem->correlatorSamplesIdx + i) % N]; //read sample
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outLoI += t * coeffLoI[i]; //correlate sample
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outLoQ += t * coeffLoQ[i];
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outHiI += t * coeffHiI[i];
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outHiQ += t * coeffHiQ[i];
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}
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outHiI >>= 12;
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outHiQ >>= 12;
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outLoI >>= 12;
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outLoQ >>= 12;
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uint64_t hi = (outHiI * outHiI) + (outHiQ * outHiQ); //calculate output tone levels
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uint64_t lo = (outLoI * outLoI) + (outLoQ * outLoQ);
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//DCD using PLL
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//PLL is running nominally at 1200 Hz (= baudrate)
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@ -443,9 +482,7 @@ static int32_t demodulate(int16_t sample, struct DemodState *dem)
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dem->dcdPll = (signed)((unsigned)(dem->dcdPll) + ((unsigned)dem->pll)); //keep PLL ticking at the frequency equal to baudrate
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uint8_t dcdSymbol = (hi > lo); //get current symbol
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if(dcdSymbol != dem->dcdLastSymbol) //tone changed
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if((sample > 0) != dem->dcdLastSymbol) //tone changed
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{
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if(abs(dem->dcdPll) < dem->dcdInc) //tone change occurred near zero
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dem->dcdCounter += dem->dcdInc; //increase DCD counter
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@ -457,7 +494,7 @@ static int32_t demodulate(int16_t sample, struct DemodState *dem)
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dem->dcdPll = (int)(dem->dcdPll * dem->dcdAdjust); //adjust PLL
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}
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dem->dcdLastSymbol = dcdSymbol; //store last symbol for symbol change detection
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dem->dcdLastSymbol = sample > 0; //store last symbol for symbol change detection
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if(dem->dcdCounter > dem->dcdMax) //maximum DCD counter value reached
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dem->dcdCounter = dem->dcdMax; //avoid "sticky" DCD and counter overflow
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@ -467,12 +504,43 @@ static int32_t demodulate(int16_t sample, struct DemodState *dem)
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else //below DCD threshold
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dem->dcd = 0; //no DCD
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return filter(&dem->lpf, hi - lo) > 0;
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//TODO: check if demodulator works well after all changes
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sample = filter(&dem->lpf, sample);
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if(ModemConfig.modem == MODEM_9600)
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{
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//AGC
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if(sample >= dem->peak)
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{
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dem->peak += (((int32_t)(AGC9600_ATTACK * (float)32768) * (int32_t)(sample - dem->peak)) >> 15);
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}
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else
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{
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dem->peak += (((int32_t)(AGC9600_DECAY * (float)32768) * (int32_t)(sample - dem->peak)) >> 15);
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}
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if(sample <= dem->valley)
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{
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dem->valley += (((int32_t)(AGC9600_ATTACK * (float)32768) * (int32_t)(sample - dem->valley)) >> 15);
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}
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else
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{
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dem->valley += (((int32_t)(AGC9600_DECAY * (float)32768) * (int32_t)(sample - dem->valley)) >> 15);
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}
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//remove DC component (subtract average value of peaks)
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//and normalize to 32768 peak-to-peak (-16384:16384)
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//32768 is equal to 1 << 15
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if(dem->peak > dem->valley)
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{
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sample = ((((int32_t)(sample) - ((int32_t)(dem->peak + dem->valley) >> 1)) << 15) / (int32_t)(dem->peak - dem->valley));
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}
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}
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return sample > 0;
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}
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/**
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* @brief Decode received symbol: bit recovery, NRZI decoding and pass the decoded bit to higher level protocol
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* @param[in] symbol Received symbol
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@ -497,12 +565,16 @@ static void decode(uint8_t symbol, uint8_t demod)
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{
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dem->syncSymbols <<= 1; //shift recovered (received, synchronized) bit register
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uint8_t t = dem->rawSymbols & 0x07; //take last three symbols for sampling. Seems that 1 symbol is not enough, but 3 symbols work well
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if(t == 0b111 || t == 0b110 || t == 0b101 || t == 0b011) //if there are 2 or 3 ones, then the received symbol is 1
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{
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dem->syncSymbols |= 1; //push to recovered symbols register
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}
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//if there 2 or 3 zeros, no need to add anything to the register
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uint8_t sym = dem->rawSymbols & 0x07; //take last three symbols for sampling. Seems that 1 symbol is not enough, but 3 symbols work well
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if(sym == 0b111 || sym == 0b110 || sym == 0b101 || sym == 0b011) //if there are 2 or 3 ones, then the received symbol is 1
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sym = 1;
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else
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sym = 0;
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if(ModemConfig.modem == MODEM_9600)
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sym = scramble(sym); //descramble
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dem->syncSymbols |= sym;
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//NRZI decoding
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if (((dem->syncSymbols & 0x03) == 0b11) || ((dem->syncSymbols & 0x03) == 0b00)) //two last symbols are the same - no symbol transition - decoded bit 1
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@ -540,29 +612,23 @@ void ModemTxTestStart(enum ModemTxTestMode type)
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setPtt(1); //PTT on
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txTestState = type;
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//DAC timer
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TIM1->PSC = 17; //72/18=4 MHz
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TIM1->DIER = TIM_DIER_UIE; //enable interrupt
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TIM1->CR1 |= TIM_CR1_CEN; //enable timer
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TIM2->CR1 &= ~TIM_CR1_CEN; //disable RX timer
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TIM1->CR1 |= TIM_CR1_CEN; //enable DAC timer
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NVIC_DisableIRQ(DMA1_Channel2_IRQn); //disable RX DMA interrupt
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NVIC_EnableIRQ(TIM1_UP_IRQn); //enable timer 1 for PWM
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NVIC_EnableIRQ(TIM1_UP_IRQn); //enable DAC interrupt
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if(type == TEST_MARK)
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{
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TIM1->ARR = markStep;
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} else if(type == TEST_SPACE)
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}
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else if(type == TEST_SPACE)
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{
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TIM1->ARR = spaceStep;
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}
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else //alternating tones
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{
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//enable baudrate generator
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TIM3->PSC = 71; //72/72=1 MHz
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TIM3->DIER = TIM_DIER_UIE; //enable interrupt
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TIM3->ARR = baudRateStep; //set timer interval
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TIM3->CR1 = TIM_CR1_CEN; //enable timer
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NVIC_EnableIRQ(TIM3_IRQn); //enable interrupt in NVIC
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}
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@ -573,8 +639,8 @@ void ModemTxTestStop(void)
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{
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txTestState = TEST_DISABLED;
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TIM3->CR1 &= ~TIM_CR1_CEN; //turn off timers
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TIM1->CR1 &= ~TIM_CR1_CEN;
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TIM3->CR1 &= ~TIM_CR1_CEN; //disable baudrate timer
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TIM1->CR1 &= ~TIM_CR1_CEN; //disable DAC timer
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TIM2->CR1 |= TIM_CR1_CEN; //enable RX timer
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NVIC_DisableIRQ(TIM3_IRQn);
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@ -589,14 +655,6 @@ void ModemTransmitStart(void)
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{
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setPtt(1); //PTT on
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TIM1->PSC = 17;
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TIM1->DIER |= TIM_DIER_UIE;
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TIM3->PSC = 71;
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TIM3->DIER |= TIM_DIER_UIE;
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TIM3->ARR = baudRateStep;
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TIM3->CR1 = TIM_CR1_CEN;
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TIM1->CR1 = TIM_CR1_CEN;
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TIM2->CR1 &= ~TIM_CR1_CEN;
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@ -612,7 +670,6 @@ void ModemTransmitStart(void)
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*/
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void ModemTransmitStop(void)
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{
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TIM2->CR1 |= TIM_CR1_CEN;
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TIM3->CR1 &= ~TIM_CR1_CEN;
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TIM1->CR1 &= ~TIM_CR1_CEN;
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@ -628,14 +685,14 @@ void ModemTransmitStop(void)
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/**
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* @brief Controls PTT output
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* @param[in] state 0 - PTT off, 1 - PTT on
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* @param state 0 - PTT off, 1 - PTT on
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*/
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static void setPtt(uint8_t state)
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{
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if(state)
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PTT_ON;
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GPIOB->BSRR = GPIO_BSRR_BS7;
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else
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PTT_OFF;
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GPIOB->BSRR = GPIO_BSRR_BR7;
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}
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@ -646,98 +703,9 @@ void ModemInit(void)
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{
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memset(demodState, 0, sizeof(demodState));
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if((ModemConfig.modem == MODEM_1200) || (ModemConfig.modem == MODEM_1200_V23))
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{
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demodCount = 2;
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N = N1200;
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baudRate = 1200.f;
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demodState[0].pllStep = PLL1200_STEP;
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demodState[0].pllLockedAdjust = PLL1200_LOCKED_TUNE;
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demodState[0].pllNotLockedAdjust = PLL1200_NOT_LOCKED_TUNE;
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demodState[0].dcdMax = DCD1200_MAXPULSE;
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demodState[0].dcdThres = DCD1200_THRES;
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demodState[0].dcdInc = DCD1200_INC;
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demodState[0].dcdDec = DCD1200_DEC;
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demodState[0].dcdAdjust = DCD1200_PLLTUNE;
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demodState[1].pllStep = PLL1200_STEP;
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demodState[1].pllLockedAdjust = PLL1200_LOCKED_TUNE;
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demodState[1].pllNotLockedAdjust = PLL1200_NOT_LOCKED_TUNE;
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demodState[1].dcdMax = DCD1200_MAXPULSE;
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demodState[1].dcdThres = DCD1200_THRES;
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demodState[1].dcdInc = DCD1200_INC;
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demodState[1].dcdDec = DCD1200_DEC;
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demodState[1].dcdAdjust = DCD1200_PLLTUNE;
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demodState[0].prefilter = PREFILTER_NONE;
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demodState[0].lpf.coeffs = lpf1200;
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demodState[0].lpf.taps = sizeof(lpf1200) / sizeof(*lpf1200);
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demodState[0].lpf.gainShift = 0; //not important, output is always compared with 0
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demodState[1].lpf.coeffs = lpf1200;
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demodState[1].lpf.taps = sizeof(lpf1200) / sizeof(*lpf1200);
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demodState[1].lpf.gainShift = 0; //not important, output is always compared with 0
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if(ModemConfig.flatAudioIn) //when used with flat audio input, use deemphasis and flat modems
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{
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demodState[1].prefilter = PREFILTER_DEEMPHASIS;
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demodState[1].bpf.coeffs = bpf1200Inv;
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demodState[1].bpf.taps = sizeof(bpf1200Inv) / sizeof(*bpf1200Inv);
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demodState[1].bpf.gainShift = 15;
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}
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else //when used with normal (filtered) audio input, use flat and preemphasis modems
|
||||
{
|
||||
demodState[1].prefilter = PREFILTER_PREEMPHASIS;
|
||||
demodState[1].bpf.coeffs = bpf1200;
|
||||
demodState[1].bpf.taps = sizeof(bpf1200) / sizeof(*bpf1200);
|
||||
demodState[1].bpf.gainShift = 15;
|
||||
}
|
||||
|
||||
if(ModemConfig.modem == MODEM_1200) //Bell 202
|
||||
{
|
||||
markFreq = 1200.f;
|
||||
spaceFreq = 2200.f;
|
||||
}
|
||||
else //V.23
|
||||
{
|
||||
markFreq = 1300.f;
|
||||
spaceFreq = 2100.f;
|
||||
}
|
||||
}
|
||||
else if(ModemConfig.modem == MODEM_300)
|
||||
{
|
||||
demodCount = 1;
|
||||
N = N300;
|
||||
baudRate = 300.f;
|
||||
markFreq = 1600.f;
|
||||
markFreq = 1800.f;
|
||||
|
||||
demodState[0].pllStep = PLL300_STEP;
|
||||
demodState[0].pllLockedAdjust = PLL300_LOCKED_TUNE;
|
||||
demodState[0].pllNotLockedAdjust = PLL300_NOT_LOCKED_TUNE;
|
||||
demodState[0].dcdMax = DCD300_MAXPULSE;
|
||||
demodState[0].dcdThres = DCD300_THRES;
|
||||
demodState[0].dcdInc = DCD300_INC;
|
||||
demodState[0].dcdDec = DCD300_DEC;
|
||||
demodState[0].dcdAdjust = DCD300_PLLTUNE;
|
||||
|
||||
demodState[0].prefilter = PREFILTER_FLAT;
|
||||
demodState[0].bpf.coeffs = bpf300;
|
||||
demodState[0].bpf.taps = sizeof(bpf300) / sizeof(*bpf300);
|
||||
demodState[0].bpf.gainShift = 16;
|
||||
demodState[0].lpf.coeffs = lpf300;
|
||||
demodState[0].lpf.taps = sizeof(lpf300) / sizeof(*lpf300);
|
||||
demodState[0].lpf.gainShift = 0; //not important, output is always compared with 0
|
||||
}
|
||||
|
||||
markStep = 4000000 / (DAC_SINE_SIZE * markFreq) - 1;
|
||||
spaceStep = 4000000 / (DAC_SINE_SIZE * spaceFreq) - 1;
|
||||
baudRateStep = 1000000 / baudRate - 1;
|
||||
|
||||
|
||||
/**
|
||||
* TIM1 is used for pushing samples to DAC (R2R or PWM) at 4 MHz
|
||||
* TIM3 is the baudrate generator for TX running at 1 MHz
|
||||
* TIM1 is used for pushing samples to DAC (R2R or PWM) (clocked at 4 MHz)
|
||||
* TIM3 is the baudrate generator for TX (clocked at 1 MHz)
|
||||
* TIM4 is the PWM generator with no software interrupt
|
||||
* TIM2 is the RX sampling timer with no software interrupt, but it directly calls DMA
|
||||
*/
|
||||
|
|
@ -806,10 +774,138 @@ void ModemInit(void)
|
|||
|
||||
NVIC_EnableIRQ(DMA1_Channel2_IRQn);
|
||||
|
||||
TIM2->PSC = 17; //72/18=4 MHz
|
||||
|
||||
//RX sampling timer
|
||||
TIM2->PSC = 8; //72/9=8 MHz
|
||||
TIM2->DIER |= TIM_DIER_UDE; //enable calling DMA on timer tick
|
||||
TIM2->ARR = 103; //4MHz / 104 =~38400 Hz (4*9600 Hz for 4x oversampling)
|
||||
TIM2->CR1 |= TIM_CR1_CEN; //enable timer
|
||||
|
||||
//TX DAC timer
|
||||
TIM1->PSC = 17; //72/18=4 MHz
|
||||
TIM1->DIER |= TIM_DIER_UIE;
|
||||
|
||||
//baudrate timer
|
||||
TIM3->PSC = 71; //72/72=1 MHz
|
||||
TIM3->DIER |= TIM_DIER_UIE;
|
||||
|
||||
if((ModemConfig.modem == MODEM_1200) || (ModemConfig.modem == MODEM_1200_V23))
|
||||
{
|
||||
demodCount = 2;
|
||||
N = N1200;
|
||||
baudRate = 1200.f;
|
||||
|
||||
demodState[0].pllStep = PLL1200_STEP;
|
||||
demodState[0].pllLockedAdjust = PLL1200_LOCKED_TUNE;
|
||||
demodState[0].pllNotLockedAdjust = PLL1200_NOT_LOCKED_TUNE;
|
||||
demodState[0].dcdMax = DCD1200_MAXPULSE;
|
||||
demodState[0].dcdThres = DCD1200_THRES;
|
||||
demodState[0].dcdInc = DCD1200_INC;
|
||||
demodState[0].dcdDec = DCD1200_DEC;
|
||||
demodState[0].dcdAdjust = DCD1200_PLLTUNE;
|
||||
|
||||
demodState[1].pllStep = PLL1200_STEP;
|
||||
demodState[1].pllLockedAdjust = PLL1200_LOCKED_TUNE;
|
||||
demodState[1].pllNotLockedAdjust = PLL1200_NOT_LOCKED_TUNE;
|
||||
demodState[1].dcdMax = DCD1200_MAXPULSE;
|
||||
demodState[1].dcdThres = DCD1200_THRES;
|
||||
demodState[1].dcdInc = DCD1200_INC;
|
||||
demodState[1].dcdDec = DCD1200_DEC;
|
||||
demodState[1].dcdAdjust = DCD1200_PLLTUNE;
|
||||
|
||||
demodState[0].prefilter = PREFILTER_NONE;
|
||||
demodState[0].lpf.coeffs = lpf1200;
|
||||
demodState[0].lpf.taps = sizeof(lpf1200) / sizeof(*lpf1200);
|
||||
demodState[0].lpf.gainShift = 0; //not important, output is always compared with 0
|
||||
demodState[1].lpf.coeffs = lpf1200;
|
||||
demodState[1].lpf.taps = sizeof(lpf1200) / sizeof(*lpf1200);
|
||||
demodState[1].lpf.gainShift = 0; //not important, output is always compared with 0
|
||||
|
||||
if(ModemConfig.flatAudioIn) //when used with flat audio input, use deemphasis and flat modems
|
||||
{
|
||||
demodState[1].prefilter = PREFILTER_DEEMPHASIS;
|
||||
demodState[1].bpf.coeffs = bpf1200Inv;
|
||||
demodState[1].bpf.taps = sizeof(bpf1200Inv) / sizeof(*bpf1200Inv);
|
||||
demodState[1].bpf.gainShift = 15;
|
||||
}
|
||||
else //when used with normal (filtered) audio input, use flat and preemphasis modems
|
||||
{
|
||||
demodState[1].prefilter = PREFILTER_PREEMPHASIS;
|
||||
demodState[1].bpf.coeffs = bpf1200;
|
||||
demodState[1].bpf.taps = sizeof(bpf1200) / sizeof(*bpf1200);
|
||||
demodState[1].bpf.gainShift = 15;
|
||||
}
|
||||
|
||||
if(ModemConfig.modem == MODEM_1200) //Bell 202
|
||||
{
|
||||
markFreq = 1200.f;
|
||||
spaceFreq = 2200.f;
|
||||
}
|
||||
else //V.23
|
||||
{
|
||||
markFreq = 1300.f;
|
||||
spaceFreq = 2100.f;
|
||||
}
|
||||
|
||||
TIM2->ARR = 207; //8MHz / 208 =~38400 Hz (4*9600 Hz for 4x oversampling)
|
||||
}
|
||||
else if(ModemConfig.modem == MODEM_300)
|
||||
{
|
||||
demodCount = 1;
|
||||
N = N300;
|
||||
baudRate = 300.f;
|
||||
markFreq = 1600.f;
|
||||
spaceFreq = 1800.f;
|
||||
|
||||
demodState[0].pllStep = PLL300_STEP;
|
||||
demodState[0].pllLockedAdjust = PLL300_LOCKED_TUNE;
|
||||
demodState[0].pllNotLockedAdjust = PLL300_NOT_LOCKED_TUNE;
|
||||
demodState[0].dcdMax = DCD300_MAXPULSE;
|
||||
demodState[0].dcdThres = DCD300_THRES;
|
||||
demodState[0].dcdInc = DCD300_INC;
|
||||
demodState[0].dcdDec = DCD300_DEC;
|
||||
demodState[0].dcdAdjust = DCD300_PLLTUNE;
|
||||
|
||||
demodState[0].prefilter = PREFILTER_FLAT;
|
||||
demodState[0].bpf.coeffs = bpf300;
|
||||
demodState[0].bpf.taps = sizeof(bpf300) / sizeof(*bpf300);
|
||||
demodState[0].bpf.gainShift = 16;
|
||||
demodState[0].lpf.coeffs = lpf300;
|
||||
demodState[0].lpf.taps = sizeof(lpf300) / sizeof(*lpf300);
|
||||
demodState[0].lpf.gainShift = 0; //not important, output is always compared with 0
|
||||
|
||||
TIM2->ARR = 416; //8MHz / 416 =~19200 Hz (4*4800 Hz for 4x oversampling)
|
||||
}
|
||||
else if(ModemConfig.modem == MODEM_9600)
|
||||
{
|
||||
demodCount = 1;
|
||||
N = N9600;
|
||||
baudRate = 9600.f;
|
||||
|
||||
demodState[0].pllStep = PLL9600_STEP;
|
||||
demodState[0].pllLockedAdjust = PLL9600_LOCKED_TUNE;
|
||||
demodState[0].pllNotLockedAdjust = PLL9600_NOT_LOCKED_TUNE;
|
||||
demodState[0].dcdMax = DCD9600_MAXPULSE;
|
||||
demodState[0].dcdThres = DCD9600_THRES;
|
||||
demodState[0].dcdInc = DCD9600_INC;
|
||||
demodState[0].dcdDec = DCD9600_DEC;
|
||||
demodState[0].dcdAdjust = DCD9600_PLLTUNE;
|
||||
|
||||
demodState[0].prefilter = PREFILTER_NONE;
|
||||
//this filter will be used for RX and TX
|
||||
demodState[0].lpf.coeffs = lpf9600;
|
||||
demodState[0].lpf.taps = sizeof(lpf9600) / sizeof(*lpf9600);
|
||||
demodState[0].lpf.gainShift = 16;
|
||||
|
||||
TIM2->ARR = 51; //8MHz / 52 =~153600 Hz (4*38400 Hz for 4x oversampling)
|
||||
}
|
||||
|
||||
TIM2->CR1 |= TIM_CR1_CEN; //enable DMA timer
|
||||
|
||||
markStep = 4000000 / (DAC_SINE_SIZE * markFreq) - 1;
|
||||
spaceStep = 4000000 / (DAC_SINE_SIZE * spaceFreq) - 1;
|
||||
baudRateStep = 1000000 / baudRate - 1;
|
||||
|
||||
|
||||
TIM3->ARR = baudRateStep;
|
||||
|
||||
for(uint8_t i = 0; i < N; i++) //calculate correlator coefficients
|
||||
{
|
||||
|
|
|
|||
Ładowanie…
Reference in New Issue