spandsp  0.0.6
private/v17tx.h
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1 /*
2  * SpanDSP - a series of DSP components for telephony
3  *
4  * private/v17tx.h - ITU V.17 modem transmit part
5  *
6  * Written by Steve Underwood <steveu@coppice.org>
7  *
8  * Copyright (C) 2004 Steve Underwood
9  *
10  * All rights reserved.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU Lesser General Public License version 2.1,
14  * as published by the Free Software Foundation.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public
22  * License along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 /*! \file */
27 
28 #if !defined(_SPANDSP_PRIVATE_V17TX_H_)
29 #define _SPANDSP_PRIVATE_V17TX_H_
30 
31 /*! The number of taps in the pulse shaping/bandpass filter */
32 #define V17_TX_FILTER_STEPS 9
33 
34 /*!
35  V.17 modem transmit side descriptor. This defines the working state for a
36  single instance of a V.17 modem transmitter.
37 */
39 {
40  /*! \brief The bit rate of the modem. Valid values are 4800, 7200 and 9600. */
41  int bit_rate;
42  /*! \brief The callback function used to get the next bit to be transmitted. */
44  /*! \brief A user specified opaque pointer passed to the get_bit function. */
46 
47  /*! \brief The callback function used to report modem status changes. */
49  /*! \brief A user specified opaque pointer passed to the status function. */
51 
52  /*! \brief The gain factor needed to achieve the specified output power. */
53 #if defined(SPANDSP_USE_FIXED_POINT)
54  int32_t gain;
55 #else
56  float gain;
57 #endif
58 
59  /*! \brief The route raised cosine (RRC) pulse shaping filter buffer. */
60 #if defined(SPANDSP_USE_FIXED_POINT)
62 #else
64 #endif
65  /*! \brief Current offset into the RRC pulse shaping filter buffer. */
67 
68  /*! \brief The current state of the differential encoder. */
69  int diff;
70  /*! \brief The current state of the convolutional encoder. */
72  /*! \brief The code number for the current position in the constellation. */
74 
75  /*! \brief The register for the data scrambler. */
76  uint32_t scramble_reg;
77  /*! \brief Scrambler tap */
78  //int scrambler_tap;
79  /*! \brief TRUE if transmitting the training sequence. FALSE if transmitting user data. */
81  /*! \brief TRUE if the short training sequence is to be used. */
83  /*! \brief A counter used to track progress through sending the training sequence. */
85 
86  /*! \brief The current phase of the carrier (i.e. the DDS parameter). */
87  uint32_t carrier_phase;
88  /*! \brief The update rate for the phase of the carrier (i.e. the DDS increment). */
90  /*! \brief The current fractional phase of the baud timing. */
92 
93  /*! \brief A pointer to the constellation currently in use. */
94 #if defined(SPANDSP_USE_FIXED_POINT)
96 #else
98 #endif
99  /*! \brief The current number of data bits per symbol. This does not include
100  the redundant bit. */
102  /*! \brief The get_bit function in use at any instant. */
104  /*! \brief Error and flow logging control */
106 };
107 
108 #endif
109 /*- End of file ------------------------------------------------------------*/