00001 /* 00002 * SpanDSP - a series of DSP components for telephony 00003 * 00004 * private/v27ter_tx.h - ITU V.27ter modem transmit part 00005 * 00006 * Written by Steve Underwood <steveu@coppice.org> 00007 * 00008 * Copyright (C) 2003 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 00026 #if !defined(_SPANDSP_PRIVATE_V27TER_TX_H_) 00027 #define _SPANDSP_PRIVATE_V27TER_TX_H_ 00028 00029 /*! The number of taps in the pulse shaping/bandpass filter */ 00030 #define V27TER_TX_FILTER_STEPS 9 00031 00032 /*! 00033 V.27ter modem transmit side descriptor. This defines the working state for a 00034 single instance of a V.27ter modem transmitter. 00035 */ 00036 struct v27ter_tx_state_s 00037 { 00038 /*! \brief The bit rate of the modem. Valid values are 2400 and 4800. */ 00039 int bit_rate; 00040 /*! \brief The callback function used to get the next bit to be transmitted. */ 00041 get_bit_func_t get_bit; 00042 /*! \brief A user specified opaque pointer passed to the get_bit function. */ 00043 void *get_bit_user_data; 00044 00045 /*! \brief The callback function used to report modem status changes. */ 00046 modem_status_func_t status_handler; 00047 /*! \brief A user specified opaque pointer passed to the status function. */ 00048 void *status_user_data; 00049 00050 #if defined(SPANDSP_USE_FIXED_POINT) 00051 /*! \brief The gain factor needed to achieve the specified output power at 2400bps. */ 00052 int16_t gain_2400; 00053 /*! \brief The gain factor needed to achieve the specified output power at 4800bps. */ 00054 int16_t gain_4800; 00055 /*! \brief The root raised cosine (RRC) pulse shaping filter buffer. */ 00056 int16_t rrc_filter_re[V27TER_TX_FILTER_STEPS]; 00057 int16_t rrc_filter_im[V27TER_TX_FILTER_STEPS]; 00058 #else 00059 /*! \brief The gain factor needed to achieve the specified output power at 2400bps. */ 00060 float gain_2400; 00061 /*! \brief The gain factor needed to achieve the specified output power at 4800bps. */ 00062 float gain_4800; 00063 /*! \brief The root raised cosine (RRC) pulse shaping filter buffer. */ 00064 float rrc_filter_re[V27TER_TX_FILTER_STEPS]; 00065 float rrc_filter_im[V27TER_TX_FILTER_STEPS]; 00066 #endif 00067 00068 /*! \brief Current offset into the RRC pulse shaping filter buffer. */ 00069 int rrc_filter_step; 00070 00071 /*! \brief The register for the training and data scrambler. */ 00072 uint32_t scramble_reg; 00073 /*! \brief A counter for the number of consecutive bits of repeating pattern through 00074 the scrambler. */ 00075 int scrambler_pattern_count; 00076 /*! \brief TRUE if transmitting the training sequence, or shutting down transmission. 00077 FALSE if transmitting user data. */ 00078 int in_training; 00079 /*! \brief A counter used to track progress through sending the training sequence. */ 00080 int training_step; 00081 00082 /*! \brief The current phase of the carrier (i.e. the DDS parameter). */ 00083 uint32_t carrier_phase; 00084 /*! \brief The update rate for the phase of the carrier (i.e. the DDS increment). */ 00085 int32_t carrier_phase_rate; 00086 /*! \brief The current fractional phase of the baud timing. */ 00087 int baud_phase; 00088 /*! \brief The code number for the current position in the constellation. */ 00089 int constellation_state; 00090 /*! \brief The get_bit function in use at any instant. */ 00091 get_bit_func_t current_get_bit; 00092 /*! \brief Error and flow logging control */ 00093 logging_state_t logging; 00094 }; 00095 00096 #endif 00097 /*- End of file ------------------------------------------------------------*/
1.6.1