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Version 1.0 - Initial commit Changes to be committed: new file: .gitattributes new file: .gitignore new file: APRStt-Implementation-Notes.pdf new file: CHANGES.txt new file: LICENSE-dire-wolf.txt new file: LICENSE-other.txt new file: Makefile.linux new file: Makefile.win new file: Quick-Start-Guide-Windows.pdf new file: Raspberry-Pi-APRS.pdf new file: User-Guide.pdf new file: aclients.c new file: aprs_tt.c new file: aprs_tt.h new file: atest.c new file: audio.c new file: audio.h new file: audio_win.c new file: ax25_pad.c new file: ax25_pad.h new file: beacon.c new file: beacon.h new file: config.c new file: config.h new file: decode_aprs.c new file: decode_aprs.h new file: dedupe.c new file: dedupe.h new file: demod.c new file: demod.h new file: demod_9600.c new file: demod_9600.h new file: demod_afsk.c new file: demod_afsk.h new file: digipeater.c new file: digipeater.h new file: direwolf.c new file: direwolf.conf new file: direwolf.desktop new file: direwolf.h new file: dsp.c new file: dsp.h new file: dtmf.c new file: dtmf.h new file: dw-icon.ico new file: dw-icon.png new file: dw-icon.rc new file: dw-start.sh new file: dwgps.c new file: dwgps.h new file: encode_aprs.c new file: encode_aprs.h new file: fcs_calc.c new file: fcs_calc.h new file: fsk_demod_agc.h new file: fsk_demod_state.h new file: fsk_filters.h new file: fsk_gen_filter.h new file: gen_packets.c new file: gen_tone.c new file: gen_tone.h new file: hdlc_rec.c new file: hdlc_rec.h new file: hdlc_rec2.c new file: hdlc_rec2.h new file: hdlc_send.c new file: hdlc_send.h new file: igate.c new file: igate.h new file: kiss.c new file: kiss.h new file: kiss_frame.c new file: kiss_frame.h new file: kissnet.c new file: kissnet.h new file: latlong.c new file: latlong.h new file: ll2utm.c new file: misc/README-dire-wolf.txt new file: misc/strcasestr.c new file: misc/strsep.c new file: misc/strtok_r.c new file: morse.c new file: multi_modem.c new file: multi_modem.h new file: ptt.c new file: ptt.h new file: pttest.c new file: rdq.c new file: rdq.h new file: redecode.c new file: redecode.h new file: regex/COPYING new file: regex/INSTALL new file: regex/LICENSES new file: regex/NEWS new file: regex/README new file: regex/README-dire-wolf.txt new file: regex/re_comp.h new file: regex/regcomp.c new file: regex/regex.c new file: regex/regex.h new file: regex/regex_internal.c new file: regex/regex_internal.h new file: regex/regexec.c new file: rrbb.c new file: rrbb.h new file: server.c new file: server.h new file: symbols-new.txt new file: symbols.c new file: symbols.h new file: symbolsX.txt new file: textcolor.c new file: textcolor.h new file: tocalls.txt new file: tq.c new file: tq.h new file: tt_text.c new file: tt_text.h new file: tt_user.c new file: tt_user.h new file: tune.h new file: udp_test.c new file: utm/LatLong-UTMconversion.c new file: utm/LatLong-UTMconversion.h new file: utm/README.txt new file: utm/SwissGrid.cpp new file: utm/UTMConversions.cpp new file: utm/constants.h new file: utm2ll.c new file: version.h new file: xmit.c new file: xmit.h
2015-07-27 00:35:07 +00:00
//
// This file is part of Dire Wolf, an amateur radio packet TNC.
//
// Copyright (C) 2011 John Langner, WB2OSZ
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
1.4 development snapshot C. IBEACON for IGate statistics. NMEA style waypoints. Clean up compile warnings and header file use for Windows.
2016-07-03 22:09:34 +00:00
#include "direwolf.h"
Version 1.0 - Initial commit Changes to be committed: new file: .gitattributes new file: .gitignore new file: APRStt-Implementation-Notes.pdf new file: CHANGES.txt new file: LICENSE-dire-wolf.txt new file: LICENSE-other.txt new file: Makefile.linux new file: Makefile.win new file: Quick-Start-Guide-Windows.pdf new file: Raspberry-Pi-APRS.pdf new file: User-Guide.pdf new file: aclients.c new file: aprs_tt.c new file: aprs_tt.h new file: atest.c new file: audio.c new file: audio.h new file: audio_win.c new file: ax25_pad.c new file: ax25_pad.h new file: beacon.c new file: beacon.h new file: config.c new file: config.h new file: decode_aprs.c new file: decode_aprs.h new file: dedupe.c new file: dedupe.h new file: demod.c new file: demod.h new file: demod_9600.c new file: demod_9600.h new file: demod_afsk.c new file: demod_afsk.h new file: digipeater.c new file: digipeater.h new file: direwolf.c new file: direwolf.conf new file: direwolf.desktop new file: direwolf.h new file: dsp.c new file: dsp.h new file: dtmf.c new file: dtmf.h new file: dw-icon.ico new file: dw-icon.png new file: dw-icon.rc new file: dw-start.sh new file: dwgps.c new file: dwgps.h new file: encode_aprs.c new file: encode_aprs.h new file: fcs_calc.c new file: fcs_calc.h new file: fsk_demod_agc.h new file: fsk_demod_state.h new file: fsk_filters.h new file: fsk_gen_filter.h new file: gen_packets.c new file: gen_tone.c new file: gen_tone.h new file: hdlc_rec.c new file: hdlc_rec.h new file: hdlc_rec2.c new file: hdlc_rec2.h new file: hdlc_send.c new file: hdlc_send.h new file: igate.c new file: igate.h new file: kiss.c new file: kiss.h new file: kiss_frame.c new file: kiss_frame.h new file: kissnet.c new file: kissnet.h new file: latlong.c new file: latlong.h new file: ll2utm.c new file: misc/README-dire-wolf.txt new file: misc/strcasestr.c new file: misc/strsep.c new file: misc/strtok_r.c new file: morse.c new file: multi_modem.c new file: multi_modem.h new file: ptt.c new file: ptt.h new file: pttest.c new file: rdq.c new file: rdq.h new file: redecode.c new file: redecode.h new file: regex/COPYING new file: regex/INSTALL new file: regex/LICENSES new file: regex/NEWS new file: regex/README new file: regex/README-dire-wolf.txt new file: regex/re_comp.h new file: regex/regcomp.c new file: regex/regex.c new file: regex/regex.h new file: regex/regex_internal.c new file: regex/regex_internal.h new file: regex/regexec.c new file: rrbb.c new file: rrbb.h new file: server.c new file: server.h new file: symbols-new.txt new file: symbols.c new file: symbols.h new file: symbolsX.txt new file: textcolor.c new file: textcolor.h new file: tocalls.txt new file: tq.c new file: tq.h new file: tt_text.c new file: tt_text.h new file: tt_user.c new file: tt_user.h new file: tune.h new file: udp_test.c new file: utm/LatLong-UTMconversion.c new file: utm/LatLong-UTMconversion.h new file: utm/README.txt new file: utm/SwissGrid.cpp new file: utm/UTMConversions.cpp new file: utm/constants.h new file: utm2ll.c new file: version.h new file: xmit.c new file: xmit.h
2015-07-27 00:35:07 +00:00
#include <stdio.h>
/*
* Calculate the FCS for an AX.25 frame.
*/
#include "fcs_calc.h"
static const unsigned short ccitt_table[256] = {
// from http://www.ietf.org/rfc/rfc1549.txt
0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
};
/*
* Use this for an AX.25 frame.
*/
unsigned short fcs_calc (unsigned char *data, int len)
{
unsigned short crc = 0xffff;
int j;
for (j=0; j<len; j++) {
crc = ((crc) >> 8) ^ ccitt_table[((crc) ^ data[j]) & 0xff];
}
return ( crc ^ 0xffff );
}
KISS TNC enhancements: Multiple TCP clients, serial port for Linux, polling for Bluetooth device.
2017-05-03 21:41:37 +00:00
/*
* CRC is also used for duplicate checking for the digipeater and IGate.
* A packet is considered a duplicate if the source, destination, and
* information parts match. In other words, we ignore the via path
* which changes along the way.
* Rather than keeping a variable length string we just keep a 16 bit
* CRC which takes less memory and processing to compare.
*
* This can result in occasional false matches. If we had a random
* 16 bit number, there is a 1/65536 ( = 0.0015 % ) chance that it will
* match and we will drop something that should be passed along.
*
* Looking at it another way, there is a 0.9999847412109375 (out of 1)
* probability of doing the right thing.
*/
Version 1.0 - Initial commit Changes to be committed: new file: .gitattributes new file: .gitignore new file: APRStt-Implementation-Notes.pdf new file: CHANGES.txt new file: LICENSE-dire-wolf.txt new file: LICENSE-other.txt new file: Makefile.linux new file: Makefile.win new file: Quick-Start-Guide-Windows.pdf new file: Raspberry-Pi-APRS.pdf new file: User-Guide.pdf new file: aclients.c new file: aprs_tt.c new file: aprs_tt.h new file: atest.c new file: audio.c new file: audio.h new file: audio_win.c new file: ax25_pad.c new file: ax25_pad.h new file: beacon.c new file: beacon.h new file: config.c new file: config.h new file: decode_aprs.c new file: decode_aprs.h new file: dedupe.c new file: dedupe.h new file: demod.c new file: demod.h new file: demod_9600.c new file: demod_9600.h new file: demod_afsk.c new file: demod_afsk.h new file: digipeater.c new file: digipeater.h new file: direwolf.c new file: direwolf.conf new file: direwolf.desktop new file: direwolf.h new file: dsp.c new file: dsp.h new file: dtmf.c new file: dtmf.h new file: dw-icon.ico new file: dw-icon.png new file: dw-icon.rc new file: dw-start.sh new file: dwgps.c new file: dwgps.h new file: encode_aprs.c new file: encode_aprs.h new file: fcs_calc.c new file: fcs_calc.h new file: fsk_demod_agc.h new file: fsk_demod_state.h new file: fsk_filters.h new file: fsk_gen_filter.h new file: gen_packets.c new file: gen_tone.c new file: gen_tone.h new file: hdlc_rec.c new file: hdlc_rec.h new file: hdlc_rec2.c new file: hdlc_rec2.h new file: hdlc_send.c new file: hdlc_send.h new file: igate.c new file: igate.h new file: kiss.c new file: kiss.h new file: kiss_frame.c new file: kiss_frame.h new file: kissnet.c new file: kissnet.h new file: latlong.c new file: latlong.h new file: ll2utm.c new file: misc/README-dire-wolf.txt new file: misc/strcasestr.c new file: misc/strsep.c new file: misc/strtok_r.c new file: morse.c new file: multi_modem.c new file: multi_modem.h new file: ptt.c new file: ptt.h new file: pttest.c new file: rdq.c new file: rdq.h new file: redecode.c new file: redecode.h new file: regex/COPYING new file: regex/INSTALL new file: regex/LICENSES new file: regex/NEWS new file: regex/README new file: regex/README-dire-wolf.txt new file: regex/re_comp.h new file: regex/regcomp.c new file: regex/regex.c new file: regex/regex.h new file: regex/regex_internal.c new file: regex/regex_internal.h new file: regex/regexec.c new file: rrbb.c new file: rrbb.h new file: server.c new file: server.h new file: symbols-new.txt new file: symbols.c new file: symbols.h new file: symbolsX.txt new file: textcolor.c new file: textcolor.h new file: tocalls.txt new file: tq.c new file: tq.h new file: tt_text.c new file: tt_text.h new file: tt_user.c new file: tt_user.h new file: tune.h new file: udp_test.c new file: utm/LatLong-UTMconversion.c new file: utm/LatLong-UTMconversion.h new file: utm/README.txt new file: utm/SwissGrid.cpp new file: utm/UTMConversions.cpp new file: utm/constants.h new file: utm2ll.c new file: version.h new file: xmit.c new file: xmit.h
2015-07-27 00:35:07 +00:00
/*
* This can be used when we want to calculate a single CRC over disjoint data.
*
* crc = crc16 (region1, sizeof(region1), 0xffff);
* crc = crc16 (region2, sizeof(region2), crc);
* crc = crc16 (region3, sizeof(region3), crc);
*/
unsigned short crc16 (unsigned char *data, int len, unsigned short seed)
{
unsigned short crc = seed;
int j;
for (j=0; j<len; j++) {
crc = ((crc) >> 8) ^ ccitt_table[((crc) ^ data[j]) & 0xff];
}
return ( crc ^ 0xffff );
}