TTY/TDD Generation support. More...
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Defines | |
#define | TDD_BYTES_PER_CHAR 2700 |
Typedefs | |
typedef struct tdd_state | TDDSTATE |
Functions | |
int | ast_tdd_gen_ecdisa (unsigned char *outbuf, int len) |
int | tdd_feed (struct tdd_state *tdd, unsigned char *ubuf, int samples) |
void | tdd_free (struct tdd_state *tdd) |
int | tdd_gen_holdtone (unsigned char *outbuf) |
int | tdd_generate (struct tdd_state *tdd, unsigned char *buf, const char *string) |
void | tdd_init (void) |
struct tdd_state * | tdd_new (void) |
TTY/TDD Generation support.
Definition in file tdd.h.
#define TDD_BYTES_PER_CHAR 2700 |
Definition at line 27 of file tdd.h.
Referenced by dahdi_sendtext().
int ast_tdd_gen_ecdisa | ( | unsigned char * | outbuf, |
int | len | ||
) |
Generate Echo Canceller disable tone (2100HZ)
outbuf | This is the buffer to receive the tone data |
len | This is the length (in samples) of the tone data to generate Returns 0 if no error, and -1 if error. |
Definition at line 143 of file tdd.c.
References ecdisa, len(), and tdd_state::pos.
Referenced by dahdi_setoption().
int tdd_feed | ( | struct tdd_state * | tdd, |
unsigned char * | ubuf, | ||
int | samples | ||
) |
Read samples into the state machine, and return character (if any).
tdd | Which state machine to act upon |
ubuf | containing your samples |
samples | number of samples contained within the buffer. |
Send received audio to the TDD demodulator. Returns -1 on error, 0 for "needs more samples", and > 0 (the character) if reception of a character is complete.
Definition at line 156 of file tdd.c.
References ast_log(), AST_MULAW, buf, calloc, free, fsk_serial(), tdd_state::fskd, len(), LOG_ERROR, LOG_NOTICE, LOG_WARNING, tdd_state::mode, tdd_state::oldlen, tdd_state::oldstuff, and tdd_decode_baudot().
Referenced by dahdi_read().
{ int mylen = len; int olen; int b = 'X'; int res; int c,x; short *buf = calloc(1, 2 * len + tdd->oldlen); short *obuf = buf; if (!buf) { ast_log(LOG_WARNING, "Out of memory\n"); return -1; } memcpy(buf, tdd->oldstuff, tdd->oldlen); mylen += tdd->oldlen / 2; for (x = 0; x < len; x++) buf[x + tdd->oldlen / 2] = AST_MULAW(ubuf[x]); c = res = 0; while (mylen >= 1320) { /* has to have enough to work on */ olen = mylen; res = fsk_serial(&tdd->fskd, buf, &mylen, &b); if (mylen < 0) { ast_log(LOG_ERROR, "fsk_serial made mylen < 0 (%d) (olen was %d)\n", mylen, olen); free(obuf); return -1; } buf += (olen - mylen); if (res < 0) { ast_log(LOG_NOTICE, "fsk_serial failed\n"); free(obuf); return -1; } if (res == 1) { /* Ignore invalid bytes */ if (b > 0x7f) continue; c = tdd_decode_baudot(tdd, b); if ((c < 1) || (c > 126)) continue; /* if not valid */ break; } } if (mylen) { memcpy(tdd->oldstuff, buf, mylen * 2); tdd->oldlen = mylen * 2; } else tdd->oldlen = 0; free(obuf); if (res) { tdd->mode = 2; /* put it in mode where it reliably puts teleprinter in correct shift mode */ return(c); } return 0; }
void tdd_free | ( | struct tdd_state * | tdd | ) |
int tdd_gen_holdtone | ( | unsigned char * | buf | ) |
Generate hold tone
outbuf | This is the buffer to receive the tone data |
Generate TDD hold tone
buf | Result buffer |
Definition at line 280 of file tdd.c.
References PUT_AUDIO_SAMPLE, and tdd_getcarrier().
{ int bytes = 0; float scont = 0.0, cr = 1.0, ci=0.0; while (scont < tddsb * 10.0) { PUT_AUDIO_SAMPLE(tdd_getcarrier(&cr, &ci, 1)); scont += 1.0; } return bytes; }
int tdd_generate | ( | struct tdd_state * | tdd, |
unsigned char * | buf, | ||
const char * | string | ||
) |
Generates a CallerID FSK stream in ulaw format suitable for transmission.
tdd | tdd structure |
buf | Buffer to use. This needs to be large enough to accomodate all the generated samples. |
string | This is the string to send. This function creates a stream of TDD data in ulaw format. It returns the size (in bytes) of the data (if it returns a size of 0, there is probably an error) |
Baudot letters
Baudot figures
Definition at line 291 of file tdd.c.
References tdd_state::charnum, tdd_state::mode, and PUT_TDD.
Referenced by dahdi_sendtext().
{ int bytes = 0; int i,x; char c; /*! Baudot letters */ static unsigned char lstr[31] = "\000E\nA SIU\rDRJNFCKTZLWHYPQOBG\000MXV"; /*! Baudot figures */ static unsigned char fstr[31] = "\0003\n- \00787\r$4',!:(5\")2\0006019?+\000./;"; /* Initial carriers (real/imaginary) */ float cr = 1.0; float ci = 0.0; float scont = 0.0; for(x = 0; str[x]; x++) { /* Do synch for each 72th character */ if ( (tdd->charnum++) % 72 == 0) PUT_TDD(tdd->mode ? 27 /* FIGS */ : 31 /* LTRS */); c = toupper(str[x]); #if 0 printf("%c",c); fflush(stdout); #endif if (c == 0) { /* send null */ PUT_TDD(0); continue; } if (c == '\r') { /* send c/r */ PUT_TDD(8); continue; } if (c == '\n') { /* send c/r and l/f */ PUT_TDD(8); PUT_TDD(2); continue; } if (c == ' ') { /* send space */ PUT_TDD(4); continue; } for (i = 0; i < 31; i++) { if (lstr[i] == c) break; } if (i < 31) { /* if we found it */ if (tdd->mode) { /* if in figs mode, change it */ PUT_TDD(31); /* Send LTRS */ tdd->mode = 0; } PUT_TDD(i); continue; } for (i = 0; i < 31; i++) { if (fstr[i] == c) break; } if (i < 31) { /* if we found it */ if (tdd->mode != 1) { /* if in ltrs mode, change it */ PUT_TDD(27); /* send FIGS */ tdd->mode = 1; } PUT_TDD(i); /* send byte */ continue; } } return bytes; }
void tdd_init | ( | void | ) |
struct tdd_state* tdd_new | ( | void | ) | [read] |
Create a TDD state machine This function returns a malloc'd instance of the tdd_state data structure. Returns a pointer to a malloc'd tdd_state structure, or NULL on error.
Definition at line 98 of file tdd.c.
References ast_log(), fsk_data::bw, calloc, tdd_state::charnum, fsk_data::cont, fsk_data::f_mark_idx, fsk_data::f_space_idx, tdd_state::fskd, fskmodem_init(), fsk_data::hdlc, fsk_data::instop, fsk_data::ispb, LOG_WARNING, tdd_state::mode, fsk_data::nbit, fsk_data::nstop, fsk_data::parity, fsk_data::pcola, fsk_data::pllids, fsk_data::pllispb, fsk_data::pllispb2, tdd_state::pos, fsk_data::spb, fsk_data::state, fsk_data::x0, and fsk_data::xi0.
Referenced by dahdi_setoption().
{ struct tdd_state *tdd; tdd = calloc(1, sizeof(*tdd)); if (tdd) { #ifdef INTEGER_CALLERID tdd->fskd.ispb = 176; /* 45.5 baud */ /* Set up for 45.5 / 8000 freq *32 to allow ints */ tdd->fskd.pllispb = (int)((8000 * 32 * 2) / 90); tdd->fskd.pllids = tdd->fskd.pllispb / 32; tdd->fskd.pllispb2 = tdd->fskd.pllispb / 2; tdd->fskd.hdlc = 0; /* Async */ tdd->fskd.nbit = 5; /* 5 bits */ tdd->fskd.instop = 1; /* integer rep of 1.5 stop bits */ tdd->fskd.parity = 0; /* No parity */ tdd->fskd.bw=0; /* Filter 75 Hz */ tdd->fskd.f_mark_idx = 0; /* 1400 Hz */ tdd->fskd.f_space_idx = 1; /* 1800 Hz */ tdd->fskd.xi0 = 0; tdd->fskd.state = 0; tdd->pos = 0; tdd->mode = 0; fskmodem_init(&tdd->fskd); #else tdd->fskd.spb = 176; /* 45.5 baud */ tdd->fskd.hdlc = 0; /* Async */ tdd->fskd.nbit = 5; /* 5 bits */ tdd->fskd.nstop = 1.5; /* 1.5 stop bits */ tdd->fskd.parity = 0; /* No parity */ tdd->fskd.bw=0; /* Filter 75 Hz */ tdd->fskd.f_mark_idx = 0; /* 1400 Hz */ tdd->fskd.f_space_idx = 1; /* 1800 Hz */ tdd->fskd.pcola = 0; /* No clue */ tdd->fskd.cont = 0; /* Digital PLL reset */ tdd->fskd.x0 = 0.0; tdd->fskd.state = 0; tdd->pos = 0; tdd->mode = 2; #endif tdd->charnum = 0; } else ast_log(LOG_WARNING, "Out of memory\n"); return tdd; }