libspandsp 0.0.4
|
00001 /* 00002 * SpanDSP - a series of DSP components for telephony 00003 * 00004 * v8.h - V.8 modem negotiation processing. 00005 * 00006 * Written by Steve Underwood <steveu@coppice.org> 00007 * 00008 * Copyright (C) 2004 Steve Underwood 00009 * 00010 * All rights reserved. 00011 * 00012 * This program is free software; you can redistribute it and/or modify 00013 * it under the terms of the GNU Lesser General Public License version 2.1, 00014 * as published by the Free Software Foundation. 00015 * 00016 * This program is distributed in the hope that it will be useful, 00017 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00018 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00019 * GNU Lesser General Public License for more details. 00020 * 00021 * You should have received a copy of the GNU Lesser General Public 00022 * License along with this program; if not, write to the Free Software 00023 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 00024 * 00025 * $Id: v8.h,v 1.22 2008/05/14 15:41:25 steveu Exp $ 00026 */ 00027 00028 /*! \file */ 00029 00030 /*! \page v8_page The V.8 modem negotiation protocol 00031 \section v8_page_sec_1 What does it do? 00032 The V.8 specification defines a procedure to be used as PSTN modem answer phone calls, 00033 which allows the modems to negotiate the optimum modem standard, which both ends can 00034 support. 00035 00036 \section v8_page_sec_2 How does it work? 00037 At startup the modems communicate using the V.21 standard at 300 bits/second. They 00038 exchange simple messages about their capabilities, and choose the modem standard they 00039 will use for data communication. The V.8 protocol then terminates, and the modems 00040 being negotiating and training with their chosen modem standard. 00041 */ 00042 00043 #if !defined(_SPANDSP_V8_H_) 00044 #define _SPANDSP_V8_H_ 00045 00046 typedef struct v8_result_s v8_result_t; 00047 00048 typedef void (v8_result_handler_t)(void *user_data, v8_result_t *result); 00049 00050 enum v8_call_function_e 00051 { 00052 V8_CALL_TBS = 0, 00053 V8_CALL_H324, 00054 V8_CALL_V18, 00055 V8_CALL_T101, 00056 V8_CALL_T30_TX, 00057 V8_CALL_T30_RX, 00058 V8_CALL_V_SERIES, 00059 V8_CALL_FUNCTION_EXTENSION 00060 }; 00061 00062 enum v8_modulation_e 00063 { 00064 V8_MOD_V17 = (1 << 0), /* V.17 half-duplex */ 00065 V8_MOD_V21 = (1 << 1), /* V.21 duplex */ 00066 V8_MOD_V22 = (1 << 2), /* V.22/V22.bis duplex */ 00067 V8_MOD_V23HALF = (1 << 3), /* V.23 half-duplex */ 00068 V8_MOD_V23 = (1 << 4), /* V.23 duplex */ 00069 V8_MOD_V26BIS = (1 << 5), /* V.23 duplex */ 00070 V8_MOD_V26TER = (1 << 6), /* V.23 duplex */ 00071 V8_MOD_V27TER = (1 << 7), /* V.23 duplex */ 00072 V8_MOD_V29 = (1 << 8), /* V.29 half-duplex */ 00073 V8_MOD_V32 = (1 << 9), /* V.32/V32.bis duplex */ 00074 V8_MOD_V34HALF = (1 << 10), /* V.34 half-duplex */ 00075 V8_MOD_V34 = (1 << 11), /* V.34 duplex */ 00076 V8_MOD_V90 = (1 << 12), /* V.90 duplex */ 00077 V8_MOD_V92 = (1 << 13), /* V.92 duplex */ 00078 00079 V8_MOD_FAILED = (1 << 15), /* Indicates failure to negotiate */ 00080 }; 00081 00082 enum v8_protocol_e 00083 { 00084 V8_PROTOCOL_NONE = 0, 00085 V8_PROTOCOL_LAPM_V42 = 1, 00086 V8_PROTOCOL_EXTENSION = 7 00087 }; 00088 00089 enum v8_pstn_access_e 00090 { 00091 V8_PSTN_ACCESS_CALL_DCE_CELLULAR = 0x20, 00092 V8_PSTN_ACCESS_ANSWER_DCE_CELLULAR = 0x40, 00093 V8_PSTN_ACCESS_DCE_ON_DIGTIAL = 0x80 00094 }; 00095 00096 enum v8_pcm_modem_availability_e 00097 { 00098 V8_PSTN_PCM_MODEM_V90_V92_ANALOGUE = 0x20, 00099 V8_PSTN_PCM_MODEM_V90_V92_DIGITAL = 0x40, 00100 V8_PSTN_PCM_MODEM_V91 = 0x80 00101 }; 00102 00103 typedef struct 00104 { 00105 /*! \brief TRUE if we are the calling modem */ 00106 int caller; 00107 /*! \brief The current state of the V8 protocol */ 00108 int state; 00109 int negotiation_timer; 00110 int ci_timer; 00111 int ci_count; 00112 fsk_tx_state_t v21tx; 00113 fsk_rx_state_t v21rx; 00114 queue_state_t *tx_queue; 00115 modem_connect_tones_tx_state_t ansam_tx; 00116 modem_connect_tones_rx_state_t ansam_rx; 00117 00118 v8_result_handler_t *result_handler; 00119 void *result_handler_user_data; 00120 00121 /*! \brief Modulation schemes available at this end. */ 00122 int available_modulations; 00123 int common_modulations; 00124 int negotiated_modulation; 00125 int far_end_modulations; 00126 00127 int call_function; 00128 int protocol; 00129 int pstn_access; 00130 int nsf_seen; 00131 int pcm_modem_availability; 00132 int t66_seen; 00133 00134 /* V8 data parsing */ 00135 unsigned int bit_stream; 00136 int bit_cnt; 00137 /* Indicates the type of message coming up */ 00138 int preamble_type; 00139 uint8_t rx_data[64]; 00140 int rx_data_ptr; 00141 00142 /*! \brief a reference copy of the last CM or JM message, used when 00143 testing for matches. */ 00144 uint8_t cm_jm_data[64]; 00145 int cm_jm_count; 00146 int got_cm_jm; 00147 int got_cj; 00148 int zero_byte_count; 00149 /*! \brief Error and flow logging control */ 00150 logging_state_t logging; 00151 } v8_state_t; 00152 00153 struct v8_result_s 00154 { 00155 int call_function; 00156 int available_modulations; 00157 int negotiated_modulation; 00158 int protocol; 00159 int pstn_access; 00160 int nsf_seen; 00161 int pcm_modem_availability; 00162 int t66_seen; 00163 }; 00164 00165 #if defined(__cplusplus) 00166 extern "C" 00167 { 00168 #endif 00169 00170 /*! Initialise a V.8 context. 00171 \brief Initialise a V.8 context. 00172 \param s The V.8 context. 00173 \param caller TRUE if caller mode, else answerer mode. 00174 \param available_modulations A bitwise list of the modulation schemes to be 00175 advertised as available here. 00176 \param result_handler The callback routine used to handle the results of negotiation. 00177 \param user_data An opaque pointer passed to the result_handler routine. 00178 \return A pointer to the V.8 context, or NULL if there was a problem. */ 00179 v8_state_t *v8_init(v8_state_t *s, 00180 int caller, 00181 int available_modulations, 00182 v8_result_handler_t *result_handler, 00183 void *user_data); 00184 00185 /*! Release a V.8 context. 00186 \brief Release a V.8 context. 00187 \param s The V.8 context. 00188 \return 0 for OK. */ 00189 int v8_release(v8_state_t *s); 00190 00191 /*! Generate a block of V.8 audio samples. 00192 \brief Generate a block of V.8 audio samples. 00193 \param s The V.8 context. 00194 \param amp The audio sample buffer. 00195 \param max_len The number of samples to be generated. 00196 \return The number of samples actually generated. 00197 */ 00198 int v8_tx(v8_state_t *s, int16_t *amp, int max_len); 00199 00200 /*! Process a block of received V.8 audio samples. 00201 \brief Process a block of received V.8 audio samples. 00202 \param s The V.8 context. 00203 \param amp The audio sample buffer. 00204 \param len The number of samples in the buffer. 00205 */ 00206 int v8_rx(v8_state_t *s, const int16_t *amp, int len); 00207 00208 /*! Log the list of supported modulations. 00209 \brief Log the list of supported modulations. 00210 \param s The V.8 context. 00211 \param modulation_schemes The list of supported modulations. */ 00212 void v8_log_supported_modulations(v8_state_t *s, int modulation_schemes); 00213 00214 const char *v8_call_function_to_str(int call_function); 00215 const char *v8_modulation_to_str(int modulation_scheme); 00216 const char *v8_protocol_to_str(int protocol); 00217 const char *v8_pstn_access_to_str(int pstn_access); 00218 const char *v8_pcm_modem_availability_to_str(int pcm_modem_availability); 00219 00220 #if defined(__cplusplus) 00221 } 00222 #endif 00223 00224 #endif 00225 /*- End of file ------------------------------------------------------------*/