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P25: Add Tait (mfid: D8) Slot Count vPDU (op: B5);

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lwvmobile
2025-01-26 13:31:54 -05:00
parent bc140ec081
commit 291e808feb
1 changed files with 33 additions and 1 deletions
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34
src/p25p2_vpdu.c
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@@ -21,7 +21,7 @@ static const uint8_t mac_msg_len[256] = {
8, 18, 0, 7, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, //8F (needed to add 81 and 8f for Harris)
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, //9F
16, 0, 0, 11, 13, 11, 11, 11, 10, 0, 0, 0, 0, 0, 0, 0, //AF
17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, //BF, B0 was 0, set to 17 (Harris again)
17, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, //BF, B0 was 0, set to 17 (Harris again), B5 Tait 0, set to 5
11, 0, 0, 8, 15, 12, 15, 32, 12, 12, 0, 27, 14, 29, 29, 32, //CF
0, 0, 0, 0, 0, 0, 9, 0, 14, 29, 11, 27, 14, 0, 40, 11, //DF
28, 0, 0, 14, 17, 14, 0, 0, 16, 8, 11, 0, 13, 19, 0, 0, //EF
@@ -1840,6 +1840,38 @@ void process_MAC_VPDU(dsd_opts * opts, dsd_state * state, int type, unsigned lon
}
//Tait Observed "tdma slot counter", this can be a single message in a facch idle, or a ndary message in a sacch channel update
if (MAC[len_a+1] == 0xB5 && MAC[len_a+2] == 0xD8)
{
uint8_t mfid = MAC[len_a+2];
uint16_t sc = (MAC[len_a+4] << 8) + MAC[len_a+5]; //its possible that not all bits in these two bytes are slots, similar to time_date_ann
uint8_t len = MAC[len_a+3]; //5 on this opcode (including opcode, mfid, len, and two bytes for slot count)
//if using the same slot counter bits as time_date_ann,
//then we can trunc the slot count to 13 bits
// sc &= 0x1FFF;
fprintf (stderr, "\n MFID %02X (Tait); Len: %d; Opcode: %02X; Slot Counter: %04X;", mfid, len, MAC[len_a+1], sc);
len_b = 5;
}
//look for other unknown Tait opcodes
if (MAC[len_a+1] != 0xB5 && MAC[len_a+2] == 0xD8)
{
uint8_t mfid = MAC[len_a+2];
uint8_t len = MAC[len_a+3];
fprintf (stderr, "\n MFID %02X (Tait); Len: %d; Opcode: %02X;", mfid, len, MAC[len_a+1]);
//dump entire payload
fprintf (stderr, " Payload: ");
for (i = 4; i < 24; i++)
fprintf (stderr, "%02llX", MAC[i+len_a]);
len_b = len;
}
/*
Maybe this is why some of these SYNC_BCST PDUs have zeroes in most fields