2 * Copyright (c) 2000 Hellmuth Michaelis. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 /*---------------------------------------------------------------------------
28 * i4b_l1lib.c - general useful L1 procedures
29 * ------------------------------------------
30 * $Id: i4b_l1lib.c,v 1.3 2000/05/29 15:41:41 hm Exp $
31 * last edit-date: [Mon May 29 15:24:21 2000]
33 *---------------------------------------------------------------------------*/
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
38 #include <sys/param.h>
39 #include <sys/systm.h>
41 #include <i4b/include/i4b_ioctl.h>
42 #include <i4b/include/i4b_trace.h>
44 #include <i4b/layer1/i4b_l1.h>
46 #define TEL_IDLE_MIN (BCH_MAX_DATALEN/2)
48 /*---------------------------------------------------------------------------*
49 * telephony silence detection
50 *---------------------------------------------------------------------------*/
52 i4b_l1_bchan_tel_silence(unsigned char *data, int len)
57 /* count idle bytes */
61 if((*data >= 0xaa) && (*data <= 0xac))
67 printf("i4b_l1_bchan_tel_silence: got %d silence bytes in frame\n", j);
70 if(j < (TEL_IDLE_MIN))