mirror of
https://github.com/f4exb/sdrangel.git
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77 lines
2.8 KiB
C
77 lines
2.8 KiB
C
/*
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*
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* This code is taken largely from on1arf's GMSK code. Original copyright below:
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*
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*
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* Copyright (C) 2011 by Kristoff Bonne, ON1ARF
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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*/
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#include "fcs.h"
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#include "descramble.h"
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#include "dstar_header.h"
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void dstar_header_decode(int radioheaderbuffer[660]) {
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int radioheaderbuffer2[660];
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unsigned char radioheader[41];
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int octetcount, bitcount, loop;
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unsigned char bit2octet[] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80};
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unsigned int FCSinheader;
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unsigned int FCScalculated;
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int len;
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scramble(radioheaderbuffer, radioheaderbuffer2);
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deinterleave(radioheaderbuffer2, radioheaderbuffer);
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len = FECdecoder(radioheaderbuffer, radioheaderbuffer2);
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memset(radioheader, 0, 41);
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// note we receive 330 bits, but we only use 328 of them (41 octets)
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// bits 329 and 330 are unused
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octetcount = 0;
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bitcount = 0;
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for (loop = 0; loop < 328; loop++) {
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if (radioheaderbuffer2[loop]) {
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radioheader[octetcount] |= bit2octet[bitcount];
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};
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bitcount++;
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// increase octetcounter and reset bitcounter every 8 bits
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if (bitcount >= 8) {
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octetcount++;
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bitcount = 0;
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}
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}
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// print header
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fprintf(stderr, "\nDSTAR HEADER: ");
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//fprintf(stderr, "FLAG1: %02X - FLAG2: %02X - FLAG3: %02X\n", radioheader[0],
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// radioheader[1], radioheader[2]);
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fprintf(stderr, "RPT 2: %c%c%c%c%c%c%c%c ", radioheader[3], radioheader[4],
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radioheader[5], radioheader[6], radioheader[7], radioheader[8],
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radioheader[9], radioheader[10]);
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fprintf(stderr, "RPT 1: %c%c%c%c%c%c%c%c ", radioheader[11], radioheader[12],
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radioheader[13], radioheader[14], radioheader[15], radioheader[16],
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radioheader[17], radioheader[18]);
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fprintf(stderr, "YOUR: %c%c%c%c%c%c%c%c ", radioheader[19], radioheader[20],
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radioheader[21], radioheader[22], radioheader[23], radioheader[24],
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radioheader[25], radioheader[26]);
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fprintf(stderr, "MY: %c%c%c%c%c%c%c%c/%c%c%c%c\n", radioheader[27],
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radioheader[28], radioheader[29], radioheader[30], radioheader[31],
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radioheader[32], radioheader[33], radioheader[34], radioheader[35],
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radioheader[36], radioheader[37], radioheader[38]);
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//FCSinheader = ((radioheader[39] << 8) | radioheader[40]) & 0xFFFF;
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//FCScalculated = calc_fcs((unsigned char*) radioheader, 39);
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//fprintf(stderr, "Check sum = %04X ", FCSinheader);
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//if (FCSinheader == FCScalculated) {
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// fprintf(stderr, "(OK)\n");
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//} else {
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// fprintf(stderr, "(NOT OK- Calculated FCS = %04X)\n", FCScalculated);
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//}; // end else - if
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}
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