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M17 - Debug LSF Frame; Pack/Repack CRC;

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lwvmobile
2024-03-07 21:21:06 -05:00
parent e20229208f
commit a30512f4e4
1 changed files with 24 additions and 10 deletions
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34
src/m17.c
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@@ -688,7 +688,7 @@ void processM17LSF(dsd_opts * opts, dsd_state * state)
//NOTE: Have not been able to get this to work successfully, but considering
//there is only one LSF frame at the beginning of TX, its probably just as easy to
//use and rely on the STR frame and embedded LSF chunk, which does work properly
int i, j, k, x;
int i, x;
uint8_t dbuf[184]; //384-bit frame - 16-bit (8 symbol) sync pattern (184 dibits)
uint8_t m17_rnd_bits[368]; //368 bits that are still scrambled (randomized)
uint8_t m17_int_bits[368]; //368 bits that are still interleaved
@@ -724,16 +724,13 @@ void processM17LSF(dsd_opts * opts, dsd_state * state)
m17_bits[i] = m17_int_bits[x];
}
j = 0; k = 0; x = 0;
// P1 Depuncture
x = 0;
for (i = 0; i < 488; i++)
{
if (p1[k++] == 1) m17_depunc[x++] = m17_bits[j++];
else m17_depunc[x++] = 0;
if (k == 61) k = 0; //61 -- should reset 8 times againt the array
if (p1[i%61] == 1)
m17_depunc[i] = m17_bits[x++];
else m17_depunc[i] = 0;
}
//debug -- values seem okay at end of run
@@ -1332,13 +1329,17 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
uint16_t crc_cmp = 0;
uint8_t lsf_packed[30];
memset (lsf_packed, 0, sizeof(lsf_packed));
for (i = 0; i < 30; i++)
for (i = 0; i < 28; i++)
lsf_packed[i] = (uint8_t)ConvertBitIntoBytes(&m17_lsf[i*8], 8);
crc_cmp = crc16m17(lsf_packed, 28);
//attach the crc16 bits to the end of the LSF data
for (i = 0; i < 16; i++) m17_lsf[224+i] = (crc_cmp >> 15-i) & 1;
//pack the CRC
for (i = 28; i < 30; i++)
lsf_packed[i] = (uint8_t)ConvertBitIntoBytes(&m17_lsf[i*8], 8);
//Craft and Send Initial LSF frame to be decoded
//LSF w/ convolutional encoding (double check array sizes)
@@ -1694,6 +1695,15 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
//send LSF frame once, if new encode session
if (new_lsf == 1)
{
//debug LSF before (see after in decoder for comparison)
// fprintf (stderr, "\n LSF: ");
// for (i = 0; i < 30; i++)
// {
// if ((i%15)==0) fprintf (stderr, "\n");
// fprintf (stderr, " %02X", lsf_packed[i]);
// }
fprintf (stderr, "\n M17 LSF (ENCODER): ");
if (opts->monitor_input_audio == 0)
processM17LSF_debug(opts, state, m17_lsfc);
@@ -1859,13 +1869,17 @@ void encodeM17STR(dsd_opts * opts, dsd_state * state)
//repack, new CRC, and update rest of lsf as well
memset (lsf_packed, 0, sizeof(lsf_packed));
for (i = 0; i < 30; i++)
for (i = 0; i < 28; i++)
lsf_packed[i] = (uint8_t)ConvertBitIntoBytes(&m17_lsf[i*8], 8);
crc_cmp = crc16m17(lsf_packed, 28);
//attach the crc16 bits to the end of the LSF data
for (i = 0; i < 16; i++) m17_lsf[224+i] = (crc_cmp >> 15-i) & 1;
//repack the CRC
for (i = 28; i < 30; i++)
lsf_packed[i] = (uint8_t)ConvertBitIntoBytes(&m17_lsf[i*8], 8);
//Recraft and Prepare New LSF frame for next encoding session
//this is primarily to make sure the LSF has the refreshed nonce
memset (m17_lsfc, 0, sizeof(m17_lsfc));