tdd.c File Reference

outbuf

do { \
   int index = (short)(rint(8192.0 * (y))); \
   *(buf++) = AST_LIN2MU(index); \
   bytes++; \
} while(0)

do { \
   *(buf++) = (a); \
   bytes++; \
} while(0)

do { \
   int x; \
   for (x=0;x<8;x++) \
      PUT_AUDIO_SAMPLE(tdd_getcarrier(&cr, &ci, 1)); \
} while(0)

00127 {
00128    int pos = 0;
00129    int cnt;
00130    while (len) {
00131       cnt = len > sizeof(ecdisa) ? sizeof(ecdisa) : len;
00132       memcpy(outbuf + pos, ecdisa, cnt);
00133       pos += cnt;
00134       len -= cnt;
00135    }
00136    return 0;
00137 }

00065 {
00066    static char ltrs[32] = { '<','E','\n','A',' ','S','I','U',
00067                             '\n','D','R','J','N','F','C','K',
00068                             'T','Z','L','W','H','Y','P','Q',
00069                             'O','B','G','^','M','X','V','^' };
00070    static char figs[32] = { '<','3','\n','-',' ',',','8','7',
00071                             '\n','$','4','\'',',','�',':','(',
00072                             '5','+',')','2','�','6','0','1',
00073                             '9','7','�','^','.','/','=','^' };
00074    int d = 0;  /* return 0 if not decodeable */
00075    switch (data) {
00076    case 0x1f:
00077       tdd->modo = 0;
00078       break;
00079    case 0x1b:
00080       tdd->modo = 1;
00081       break;
00082    default:
00083       if (tdd->modo == 0)
00084          d = ltrs[data];
00085       else
00086          d = figs[data];
00087       break;
00088    }
00089    return d;
00090 }

00140 {
00141    int mylen = len;
00142    int olen;
00143    int b = 'X';
00144    int res;
00145    int c,x;
00146    short *buf = malloc(2 * len + tdd->oldlen);
00147    short *obuf = buf;
00148    if (!buf) {
00149       ast_log(LOG_WARNING, "Out of memory\n");
00150       return -1;
00151    }
00152    memset(buf, 0, 2 * len + tdd->oldlen);
00153    memcpy(buf, tdd->oldstuff, tdd->oldlen);
00154    mylen += tdd->oldlen/2;
00155    for (x = 0; x < len; x++) 
00156       buf[x + tdd->oldlen / 2] = AST_MULAW(ubuf[x]);
00157    c = res = 0;
00158    while (mylen >= 1320) { /* has to have enough to work on */
00159       olen = mylen;
00160       res = fsk_serial(&tdd->fskd, buf, &mylen, &b);
00161       if (mylen < 0) {
00162          ast_log(LOG_ERROR, "fsk_serial made mylen < 0 (%d) (olen was %d)\n", mylen, olen);
00163          free(obuf);
00164          return -1;
00165       }
00166       buf += (olen - mylen);
00167       if (res < 0) {
00168          ast_log(LOG_NOTICE, "fsk_serial failed\n");
00169          free(obuf);
00170          return -1;
00171       }
00172       if (res == 1) {
00173          /* Ignore invalid bytes */
00174          if (b > 0x7f)
00175             continue;
00176          c = tdd_decode_baudot(tdd,b);
00177          if ((c < 1) || (c > 126))
00178             continue; /* if not valid */
00179          break;
00180       }
00181    }
00182    if (mylen) {
00183       memcpy(tdd->oldstuff, buf, mylen * 2);
00184       tdd->oldlen = mylen * 2;
00185    } else
00186       tdd->oldlen = 0;
00187    free(obuf);
00188    if (res) {
00189       tdd->mode = 2; /* put it in mode where it
00190          reliably puts teleprinter in correct shift mode */
00191       return(c);
00192    }
00193    return 0;
00194 }

00197 {
00198    free(tdd);
00199 }

00261 {
00262    int bytes=0;
00263    int i,x;
00264    char  c;
00265    /*! Baudot letters */
00266    static unsigned char lstr[31] = "\000E\nA SIU\rDRJNFCKTZLWHYPQOBG\000MXV";
00267    /*! Baudot figures */
00268    static unsigned char fstr[31] = "\0003\n- \00787\r$4',!:(5\")2\0006019?&\000./;";
00269    /* Initial carriers (real/imaginary) */
00270    float cr = 1.0;
00271    float ci = 0.0;
00272    float scont = 0.0;
00273 
00274    for(x = 0; str[x]; x++) {
00275       c = toupper(str[x]);
00276 #if   0
00277       printf("%c",c); fflush(stdout);
00278 #endif
00279       if (c == 0) { /* send null */
00280          PUT_TDD(0);
00281          continue;
00282       }
00283       if (c == '\r') { /* send c/r */
00284          PUT_TDD(8);
00285          continue;
00286       }
00287       if (c == '\n') { /* send c/r and l/f */
00288          PUT_TDD(8);
00289          PUT_TDD(2);
00290          continue;
00291       }
00292       if (c == ' ') { /* send space */
00293          PUT_TDD(4);
00294          continue;
00295       }
00296       for (i = 0; i < 31; i++) {
00297          if (lstr[i] == c)
00298             break;
00299       }
00300       if (i < 31) {        /* if we found it */
00301          if (tdd->mode) { /* if in figs mode, change it */
00302             PUT_TDD(31); /* Send LTRS */
00303             tdd->mode = 0;
00304          }
00305          PUT_TDD(i);
00306          continue;
00307       }
00308       for (i = 0; i < 31; i++) {
00309          if (fstr[i] == c)
00310             break;
00311       }
00312       if (i < 31) {             /* if we found it */
00313          if (tdd->mode != 1) { /* if in ltrs mode, change it */
00314             PUT_TDD(27);      /* send FIGS */
00315             tdd->mode = 1;
00316          }
00317          PUT_TDD(i);           /* send byte */
00318          continue;
00319       }
00320    }
00321    return bytes;
00322 }

00202 {
00203    /* Move along.  There's nothing to see here... */
00204    float t;
00205    t = *cr * dr[bit] - *ci * di[bit];
00206    *ci = *cr * di[bit] + *ci * dr[bit];
00207    *cr = t;
00208    
00209    t = 2.0 - (*cr * *cr + *ci * *ci);
00210    *cr *= t;
00211    *ci *= t;
00212    return *cr;
00213 }  

00093 {
00094    /* Initialize stuff for inverse FFT */
00095    dr[0] = cos(TDD_SPACE * 2.0 * M_PI / 8000.0);
00096    di[0] = sin(TDD_SPACE * 2.0 * M_PI / 8000.0);
00097    dr[1] = cos(TDD_MARK * 2.0 * M_PI / 8000.0);
00098    di[1] = sin(TDD_MARK * 2.0 * M_PI / 8000.0);
00099 }

00102 {
00103    struct tdd_state *tdd;
00104    tdd = malloc(sizeof(struct tdd_state));
00105    if (tdd) {
00106       memset(tdd, 0, sizeof(struct tdd_state));
00107       tdd->fskd.spb = 176;        /* 45.5 baud */
00108       tdd->fskd.hdlc = 0;         /* Async */
00109       tdd->fskd.nbit = 5;         /* 5 bits */
00110       tdd->fskd.nstop = 1.5;      /* 1.5 stop bits */
00111       tdd->fskd.parity = 0;       /* No parity */
00112       tdd->fskd.bw=0;             /* Filter 75 Hz */
00113       tdd->fskd.f_mark_idx = 0;   /* 1400 Hz */
00114       tdd->fskd.f_space_idx = 1;  /* 1800 Hz */
00115       tdd->fskd.pcola = 0;        /* No clue */
00116       tdd->fskd.cont = 0;         /* Digital PLL reset */
00117       tdd->fskd.x0 = 0.0;
00118       tdd->fskd.state = 0;
00119       tdd->pos = 0;
00120       tdd->mode = 2;
00121    } else
00122       ast_log(LOG_WARNING, "Out of memory\n");
00123    return tdd;
00124 }


Data Structures
struct	tdd_state
Defines
#define	PUT_AUDIO_SAMPLE(y)
#define	PUT_BYTE(a)
#define	PUT_TDD(byte)
#define	PUT_TDD_BAUD(bit)
#define	PUT_TDD_MARKMS
#define	PUT_TDD_STOP
#define	TDD_MARK 1400.0
#define	TDD_SPACE 1800.0
Functions
int	ast_tdd_gen_ecdisa (unsigned char *outbuf, int len)
static int	tdd_decode_baudot (struct tdd_state *tdd, unsigned char data)
int	tdd_feed (struct tdd_state tdd, unsigned char ubuf, int len)
void	tdd_free (struct tdd_state *tdd)
int	tdd_generate (struct tdd_state tdd, unsigned char buf, const char *str)
static float	tdd_getcarrier (float cr, float ci, int bit)
void	tdd_init (void)
tdd_state *	tdd_new (void)
Variables
static float	di [4]
static float	dr [4]
static float	tddsb = 176.0

Asterisk developer's documentation :: Codename Pineapple

tdd.c File Reference

Detailed Description

Data Structures

Defines

Functions

Variables

Define Documentation

Function Documentation

Variable Documentation