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M17: MPKT Decode LSF Info; Misc Output Tweaks;

This commit is contained in:
lwvmobile 2024-04-10 09:36:16 -04:00
parent 6bfbdbd9df
commit 0feb8dc73c
1 changed files with 27 additions and 3 deletions
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30
src/m17.c
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@ -2954,7 +2954,12 @@ void encodeM17PKT(dsd_opts * opts, dsd_state * state)
m17_ip_frame[k++] = (mpkt[j] >> 7-i) &1;
}
//add StreamID
//randomize ID
srand(time(NULL));
sid[0] = rand() & 0xFF;
sid[1] = rand() & 0xFF;
//add StreamID / PKT ID
for (j = 0; j < 2; j++)
{
for (i = 0; i < 8; i++)
@ -3574,18 +3579,37 @@ void processM17IPF(dsd_opts * opts, dsd_state * state)
else if (memcmp(ip_frame, mpkt, 4) == 0)
{
//convert bytes to bits
k = 0;
uint8_t ip_bits[462]; memset(ip_bits, 0, sizeof(ip_bits));
for (i = 0; i < 54; i++)
{
for (j = 0; j < 8; j++)
ip_bits[k++] = (ip_frame[i] >> (7-j)) & 1;
}
//copy Stream ID (PKT ID)
uint16_t sid = (uint16_t)ConvertBitIntoBytes(&ip_bits[32], 16);
//copy LSF
for (i = 0; i < 224; i++)
state->m17_lsf[i] = ip_bits[i+48];
//copy received CRC
uint16_t crc_ext = (ip_frame[err-2] << 8) + ip_frame[err-1];
//calculate CRC on received packet
uint16_t crc_cmp = crc16m17(ip_frame, err-2);
fprintf (stderr, "\n M17 IP MPKT: ");
fprintf (stderr, "\n M17 IP MPKT: %04X;", sid);
if (crc_ext == crc_cmp)
M17decodeLSF(state);
if (opts->payload == 1)
{
for (i = 0; i < err; i++)
{
if ( (i != 0) && (i%25)==0)
if ( (i%25)==0)
fprintf (stderr, "\n ");
fprintf (stderr, "%02X ", ip_frame[i]);
}