Files
bassofono/codice/Core/Src/tx.c
2021-07-02 22:19:04 +02:00

87 lines
2.8 KiB
C

#include <stdint.h>
#include <arm_math.h>
#include <stm32g4xx_ll_cordic.h>
#include "bassofono.h"
#include "tx.h"
volatile uint8_t half_tx_dac_buffer_empty, tx_dac_buffer_toggle;
volatile uint8_t tx_adc_buffer_ready;
// FILTRO
arm_fir_instance_q31 tx_audio_filter_I_struct, tx_audio_filter_Q_struct;
q31_t tx_audio_filter_I_state[TX_AUDIO_FILTER_BLOCK_SIZE + TX_AUDIO_FILTER_TAP_NUM - 1];
q31_t tx_audio_filter_Q_state[TX_AUDIO_FILTER_BLOCK_SIZE + TX_AUDIO_FILTER_TAP_NUM - 1];
int32_t tx_audio_filter_coeffs[TX_AUDIO_FILTER_TAP_NUM];
void tx_mixer(uint16_t *out, uint16_t size, q31_t *I_in, q31_t *Q_in, int32_t nco_freq){
uint16_t i = 0;
int32_t sin, cos, tmp;
static int32_t phase_accu;
// perche?
nco_freq = nco_freq>>2;
LL_CORDIC_WriteData(CORDIC, phase_accu);
while(i < (size * 2)){
tmp = LL_CORDIC_ReadData(CORDIC);
phase_accu += nco_freq;
LL_CORDIC_WriteData(CORDIC, phase_accu);
sin = (int16_t)tmp;
cos = tmp>>16;
// out[i] = (int32_t)cos;
// out[i] = 2000;
out[i] = cos>>4;
// out[i] = (I_in[i] * sin) + (Q_in[i] * cos);
i++;
}
tmp = LL_CORDIC_ReadData(CORDIC);
}
// modulatori
void ssb_modulator(q31_t *out_I, q31_t *out_Q, uint16_t size, q31_t *in, q31_t nco_freq){
uint16_t i;
static int32_t phase_accu;
int32_t sin, cos, tmp;
LL_CORDIC_WriteData(CORDIC, phase_accu);
i = 0;
while(i < size){
tmp = LL_CORDIC_ReadData(CORDIC);
phase_accu += nco_freq;
LL_CORDIC_WriteData(CORDIC, phase_accu);
sin = (int16_t)tmp;
cos = tmp>>16;
out_I = sat_mult_q31(sin, in[i]);
out_Q = sat_mult_q31(cos, in[i]);
i++;
}
tmp = LL_CORDIC_ReadData(CORDIC);
}
void dc_modulator(q31_t *in, uint16_t size, q31_t *out){
uint16_t i;
i = 0;
while(i < LF_BUFFER_SIZE){
out[i] = ((in[i]*(int32_t)mic_gain))/4096;
i++;
}
}
void am_modulator(q31_t *out_I, q31_t *out_Q, uint16_t size, q31_t *in){
// SQRT (I * I + Q * Q)
uint16_t i;
q31_t acc0, acc1;
i = 0;
while(i < size){
out_I[i] = in[i];
out_Q[i] = 0;
i++;
}
}
void tx_audio_filter_init(void){
arm_fir_interpolate_init_q15 (&tx_audio_filter_I_struct, TX_AUDIO_FILTER_INTERPOLATION_FACTOR, TX_AUDIO_FILTER_TAP_NUM, tx_audio_filter_coeffs, &tx_audio_filter_I_state[0], TX_AUDIO_FILTER_BLOCK_SIZE);
arm_fir_interpolate_init_q15 (&tx_audio_filter_Q_struct, TX_AUDIO_FILTER_INTERPOLATION_FACTOR, TX_AUDIO_FILTER_TAP_NUM, tx_audio_filter_coeffs, &tx_audio_filter_Q_state[0], TX_AUDIO_FILTER_BLOCK_SIZE);
}