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EDACS: Redo Parts of EA Patch / Regroup Based on Newer Observations and Remove Overlapping Bit Range;

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lwvmobile 2024-04-13 16:19:52 -04:00
parent 0208f6240c
commit 4eb2e770c8
1 changed files with 9 additions and 10 deletions
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15
src/edacs-fme.c
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@ -813,17 +813,16 @@ void edacs(dsd_opts * opts, dsd_state * state)
int unk1 = (msg_1 & 0x70000) >> 20; //unknown 3 bit value preceeding the SGID
int sgid = (msg_1 & 0xFFFF); //patched supergroup ID
//Note: SSN is the supergroup sequence number in P25 Harris lingo, but you would think this would be kind of redundant
//since the SGID is itself a unique number as well (waste of bits), but guess that's how their systems work
//that being said, the SSN is always the same for each SGID, so those values seem to go together here as well
//Updated Observation: The 'SSN' value may not be unique in this instance, so may be an entirely different value
//altogether. Its function is still unknown, but for the sake of displaying patches, is not required.
int ssn = (msg_2 & 0xFF00000) >> 20; //this value seems to incrememnt based on SGID, so assigning 8-bit as the SSN
int unk2 = (msg_2 & 0xF0000) >> 16; //unknown 4 bit value preceeding 20-bit target value of patch
int target = (msg_2 & 0xFFFFF); //target group or individual ID (20-bit) to include in supergroup
fprintf (stderr, "%s", KWHT); //just make it stick out for now
fprintf (stderr, " System Dynamic Regroup :: SSN [%03d] SGID [%05d] Target [%07d]", ssn, sgid, target);
if (unk1) fprintf (stderr, " UNK1: [%X]", unk1); //this value seems to always be zero
if (unk2) fprintf (stderr, " UNK2: [%X]", unk2); //this value seems to always be zero
fprintf (stderr, "%s", KWHT);
fprintf (stderr, " System Dynamic Regroup :: SGID [%05d] Target [%07d]", sgid, target);
if (unk1) fprintf (stderr, " UNK1: [%01X]", unk1); //this value seems to always be zero
if (ssn) fprintf (stderr, " UNK2: [%02X]", ssn); //this may or may not be a unique value to each SGID
fprintf (stderr, "%s", KNRM);
}
//Serial Number Request (not seen in the wild, see US patent 20030190923, Figure 2b)