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#pragma once
#define MAX_MAPPING_FRAME_SIZE 79
#define M_MAX 18
/* symbol rate */
enum {
V34_S2400,
V34_S2743,
V34_S2800,
V34_S3000,
V34_S3200,
V34_S3429,
};
/* constellation parameters */
#define L_MAX 1664 /* max number of points in the constellation */
#define C_MIN -11
#define C_MAX 11
#define C_MAX_SIZE ((C_MAX-C_MIN+1)*(C_MAX-C_MIN+1))
#define C_RADIUS (2*(C_MAX-C_MIN)+1) /* max coordinate of the constellation */
#define SYNC_PATTERN 0x77FA /* (table 12) synchronisation pattern for J=8 */
#define V34_SAMPLE_RATE_NUM 10
#define V34_SAMPLE_RATE_DEN 3
#define V34_SAMPLE_RATE ((2400*V34_SAMPLE_RATE_NUM)/V34_SAMPLE_RATE_DEN)
/* size of the raised root cosine filter (for both rx & tx) */
#define RC_FILTER_SIZE 40
#define TX_BUF_SIZE (2048)
#define RX_BUF1_SIZE 256
#define RX_BUF2_SIZE 256
/* size of the complex equalizer filter */
#define EQ_FRAC 3
#define EQ_SIZE (52*EQ_FRAC)
#define AGC_WINDOW_SIZE 512 /* must be a power of two, in input samples */
#define TRELLIS_MAX_STATES 64
/* 5 times the constraint length */
#define TRELLIS_LENGTH (6*5)
/* 10 fractional bits for nyquist filters */
#define NQ_BITS 10
#define NQ_BASE (1 << NQ_BITS)
/* state of the signal processing part of the V34 transmitter */
typedef struct V34DSPState {
/* V34 parameters */
int calling; /* true if we are the caller */
int S; /* index for symbol rate */
int expanded_shape; /* true if expanded shape used */
int R; /* transmit rate (in bits/s, including aux channel) */
int conv_nb_states; /* number of states of the convolutional coder */
int use_non_linear;
int use_high_carrier;
s16 h[3][2]; /* precoding coefficients (14 bits fractional part) */
void *opaque;
get_bit_func get_bit;
put_bit_func put_bit;
/* do not modify after this */
int N; /* total number of bits in a data frame */
int W; /* number of aux bits in a data frame (0 = no aux channel) */
int J; /* number of data frame in a super frame */
int P; /* number of mapping frame in a data frame */
int b; /* max length of a mapping frame */
int r; /* counter to know the length of the mapping frame */
int K; /* mapping parameters */
int q;
int L; /* current number of points of the constellation */
int M; /* current number of rings */
int Z_1; /* previous Z value (see § 9.5) */
int mapping_frame; /* number of the mapping frame */
int rcnt, acnt; /* fractional counters to know the number of bits
in a mapping frame */
int half_data_frame_count; /* number of half data frame */
int sync_count; /* counter mod 2P for synchronisation */
s16 x[3][2]; /* 3 most recent samples for precoding (7 bit fractional part) */
int U0;
int conv_reg; /* memory of the convolutional coder */
int scrambler_reg; /* state of the self synchronizing scrambler */
float carrier_freq;
float symbol_rate;
s8 constellation[C_MAX_SIZE][2];
/* precomputed bases for the ring computation */
int g2_tab[8*(M_MAX - 1) + 1];
int g4_tab[8*(M_MAX - 1) + 1];
int g8_tab[8*(M_MAX - 1) + 1];
int z8_tab[8*(M_MAX - 1) + 1];
/* for decoding only */
u16 constellation_to_code[C_RADIUS+1][C_RADIUS+1];
/* for encoding only */
s16 *tx_filter;
s16 tx_buf[TX_BUF_SIZE][2];
int tx_buf_ptr, tx_outbuf_ptr, tx_buf_size;
int tx_filter_wsize;
int baud_num, baud_denom;
int baud_incr;
int baud_phase;
int carrier_phase;
int carrier_incr;
s16 tx_amp; /* amplitude for transmit : each symbol is multiplied
by it (1:8:7) */
int baud3_phase;
s16 *rx_filter;
int rx_filter_wsize;
s16 rx_buf1[RX_BUF1_SIZE];
int rx_buf1_ptr;
/* symbol synchronization */
s16 sync_low_mem[2];
s16 sync_low_coef[2];
s16 sync_high_mem[2];
s16 sync_high_coef[2];
s16 sync_A, sync_B, sync_C;
/* equalizer */
s32 eq_filter[EQ_SIZE][2];
s16 eq_buf[EQ_SIZE];
int eq_buf_ptr;
int eq_shift;
/* AGC */
float agc_mem;
float agc_coef;
int agc_power;
int agc_gain;
/* Viterbi decoder */
/* the previous decoded decision comming to this path. Each
decision Y[5] is coded on one byte */
u8 state_decision[TRELLIS_MAX_STATES][TRELLIS_LENGTH];
u8 state_path[TRELLIS_MAX_STATES][TRELLIS_LENGTH];
s16 state_memory[TRELLIS_LENGTH][4];
u8 u0_memory[TRELLIS_LENGTH];
int state_error[TRELLIS_MAX_STATES];
int state_error1[TRELLIS_MAX_STATES];
int trellis_ptr;
/* decoder synchronization */
int phase_4d; /* index of the current 2d symbol in the 4D symbol
(0 or 1) */
int phase_mse; /* MSE to find if we are synchronized on a 4D symbol */
int phase_mse_cnt;
s16 yy[2][2]; /* current 4D symbol */
s16 rx_mapping_frame[2*4][2];
int rx_mapping_frame_count;
/* rx state */
int sym_count;
/* current V34 protocol state */
int state;
int is_16states; /* 16 states required in the startup sequences */
/* interaction with receiver */
int J_received;
int JP_received;
} V34DSPState;
extern u8 trellis_trans_4[256][4];
extern u8 trellis_trans_8[256][4];
extern u8 trellis_trans_16[256][4];
/* V34 states */
enum {
V34_STARTUP3_S1,
V34_STARTUP3_SINV1,
V34_STARTUP3_S2,
V34_STARTUP3_SINV2,
V34_STARTUP3_PP,
V34_STARTUP3_TRN,
V34_STARTUP3_J,
V34_STARTUP3_JP,
V34_STARTUP3_WAIT_J,
V34_STARTUP4_S,
V34_STARTUP4_WAIT_JP,
V34_STARTUP4_SINV,
V34_STARTUP4_TRN,
V34_STARTUP4_MP,
V34_STARTUP4_MPP,
V34_STARTUP4_E,
V34_DATA,
/* receive only */
V34_STARTUP3_WAIT_S1,
};
void put_bits(u8 **pp, int n, int bits);
int calc_crc(u8 *buf, int size);
void v34_send_info0(V34DSPState *s, int ack);
#define DSPK_TX_FILTER_SIZE 321
extern s16 v34_dpsk_tx_filter[DSPK_TX_FILTER_SIZE];
extern s16 v34_rc_5_filter[];
extern s16 v34_rc_7_filter[];
extern s16 v34_rc_8_filter[];
extern s16 v34_rc_10_filter[];
extern s16 v34_rc_20_filter[];
extern s16 v34_rc_35_filter[];
extern s16 v34_rx_filter_2400_1600[];
extern s16 v34_rx_filter_2400_1800[];
extern s16 v34_rx_filter_2743_1646[];
extern s16 v34_rx_filter_2743_1829[];
extern s16 v34_rx_filter_2800_1680[];
extern s16 v34_rx_filter_2800_1867[];
extern s16 v34_rx_filter_3000_1800[];
extern s16 v34_rx_filter_3000_2000[];
extern s16 v34_rx_filter_3200_1829[];
extern s16 v34_rx_filter_3200_1920[];
extern s16 v34_rx_filter_3429_1959[];
/* v34eq.c */
typedef struct {
s16 re, im;
} icomplex;
#define V34_PP_SIZE 48
extern icomplex tabPP[V34_PP_SIZE];
void V34eq_init(void);
void V34_fast_equalize(V34DSPState *s, s16 *input);
typedef struct V34State {
/* V34 parameters test */
int calling; /* true if we are the caller */
int S; /* index for symbol rate */
int expanded_shape; /* true if expanded shape used */
int R; /* transmit rate (in bits/s, excluding aux channel) */
int conv_nb_states; /* number of states of the convolutional coder */
int use_non_linear;
int use_high_carrier;
int use_aux_channel;
s16 h[3][2]; /* precoding coefficients (14 bits fractional part) */
V34DSPState v34_tx;
V34DSPState v34_rx;
} V34State;
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