FreeCalypso > hg > themwi-system-sw

annotate libutil/tfo_msg_enc.c @ 209:e80f158333c5

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
mgw: correct PCMU decoding table
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 07 May 2023 21:43:02 -0800
parents 05d01e810217
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
194
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 * The function implemented in this module encodes a GSM 08.62 Extension_Block.
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 */
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 #include <stdint.h>
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 #include "osmo_bits.h"
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 /*
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 * EFR TRAU parity
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 *
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 * g(x) = x^3 + x^1 + 1
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 */
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 static const struct osmo_crc8gen_code gsm0860_efr_crc3 = {
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 .bits = 3,
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 .poly = 0x3,
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 .init = 0x0,
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 .remainder = 0x7,
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 };
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 void
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 encode_tfo_ext_words(bits_2_10, bits_12_15, ex, out)
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 unsigned bits_2_10, bits_12_15, ex;
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23 uint16_t *out;
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24 {
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 ubit_t crc_in[13];
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26 uint8_t crc;
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 uint16_to_bits(bits_2_10, crc_in, 9);
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 uint16_to_bits(bits_12_15, crc_in + 9, 4);
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 crc = osmo_crc8gen_compute_bits(&gsm0860_efr_crc3, crc_in, 13);
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 out[0] = bits_2_10;
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 out[1] = (bits_12_15 << 5) | (crc << 2) | ex;
05d01e810217 libutil: add TFO message gen function based on Osmocom crc8gen
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 }