fskmodem_float.h

Go to the documentation of this file.

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
/*! \file
 * \brief FSK Modem Support
 * \note Includes code and algorithms from the Zapata library.
 */
 
#ifndef _ASTERISK_FSKMODEM_H
#define _ASTERISK_FSKMODEM_H
 
#define PARITY_NONE     0
#define PARITY_EVEN     1
#define PARITY_ODD      2
 
 
#define NCOLA 0x4000
 
typedef struct {
    float spb;  /*!< Samples / Bit */
    int nbit;   /*!< Number of Data Bits (5,7,8) */
    float nstop;    /*!< Number of Stop Bits 1,1.5,2  */
    int parity; /*!< Parity 0=none 1=even 2=odd */
    int hdlc;   /*!< Modo Packet */
    float x0;
    float x1;
    float x2;
    float cont;
    int bw;             /*!< Bandwidth */
    double fmxv[8],fmyv[8];     /*!< filter stuff for M filter */
    int fmp;            /*!< pointer for M filter */
    double fsxv[8],fsyv[8];     /*!< filter stuff for S filter */
    int fsp;            /*!< pointer for S filter */
    double flxv[8],flyv[8];     /*!< filter stuff for L filter */
    int flp;            /*!< pointer for L filter */
    int f_mark_idx;         /*!< Mark frequency index (f_M-500)/5 */
    int f_space_idx;        /*!< Space frequency index (f_S-500)/5 */
    int state;
    int pcola;          /*!< Pointer to data queues */
    float cola_in[NCOLA];       /*!< Queue of input samples */
    float cola_filter[NCOLA];   /*!< Queue of samples after filters */
    float cola_demod[NCOLA];    /*!< Queue of demodulated samples */
} fsk_data;
 
/*! \brief Retrieve a serial byte into outbyte.
   Buffer is a pointer into a series of
   shorts and len records the number of bytes in the buffer.  len will be
   overwritten with the number of bytes left that were not consumed.
   \retval 0 Still looking for something...
   \retval 1 An output byte was received and stored in outbyte
   \retval -1 An error occured in the transmission
   He must be called with at least 80 bytes of buffer. */
int fsk_serial(fsk_data *fskd, short *buffer, int *len, int *outbyte);
 
#endif /* _ASTERISK_FSKMODEM_H */