NXDN: Tweak to Frame Sync, restore other sync patterns based on polarity; Fixes random frame skips on NXDN96 trunking;

NXDN: Initial GPS Report Commit;

NXDN: Don't assign GI, TG/RID in VCALL_ASSGN; Leads to duplicate entries in Event History, particularly when private call;

NMEA: Sentence Checker with start, end, checksum, and supplimentary string checks P25p1 Tier 1 Location Service and Also observed on old Type-D system;

LRRP: Fix LRRP.exe style reports to use date/time strings with colons and slashes;

NXDN: Tweak to DCALL to check for a selective retry when blk_num is not equal to pf_num and invalidate, we don't have the memory of the last PDU attempt (and may have successfully received it anyways, even if the radio did not);

include/dsd.h

@@ -1409,6 +1409,7 @@ void harris_lptt (dsd_opts * opts, dsd_state * state, uint8_t * input, uint32_t
 void nxdn_gps_report(dsd_opts * opts, dsd_state * state, uint8_t * input, uint32_t src);
 void utf16_to_text (dsd_state * state, uint8_t wr, uint16_t len, uint8_t * input);
 void utf8_to_text (dsd_state * state, uint8_t wr, uint16_t len, uint8_t * input);
+uint8_t nmea_sentence_checker(dsd_opts * opts, dsd_state * state, uint8_t * input, uint8_t slot, int len);
 
 //"DMR STEREO"
 void dmrBSBootstrap (dsd_opts * opts, dsd_state * state);

src/dmr_pdu.c

@@ -995,8 +995,9 @@ void dmr_locn (dsd_opts * opts, dsd_state * state, uint16_t len, uint8_t * DMR_P
     //write to LRRP file
     if (opts->lrrp_file_output == 1)
     {
-      char * timestr  = getTimeC();
+
       char * datestr  = getDateS();
+      char * timestr  = getTimeC();
 
       //open file by name that is supplied in the ncurses terminal, or cli
       FILE * pFile; //file pointer

src/dsd_frame_sync.c

@@ -1212,8 +1212,11 @@ getFrameSync (dsd_opts * opts, dsd_state * state)
           {
             strncpy (synctest10, (synctest_p - 9), 10); //FSW only
             if (
-                   (strcmp (synctest10, "3131331131") == 0 ) //this seems to be the most common 'correct' pattern on Type-C
-                || (strcmp (synctest10, "3331331131") == 0 ) //this seems to be the most common 'correct' pattern on Conventional
+                   (strcmp (synctest10, "3131331131") == 0 )
+                || (strcmp (synctest10, "3331331131") == 0 )
+                || (strcmp (synctest10, "3131331111") == 0 )
+                // || (strcmp (synctest10, "3331331111") == 0 )
+                // || (strcmp (synctest10, "3131311131") == 0 )
                 )
             {
 
@@ -1239,8 +1242,11 @@ getFrameSync (dsd_opts * opts, dsd_state * state)
           {
             strncpy (synctest10, (synctest_p - 9), 10); //FSW only
             if (
-                   (strcmp (synctest10, "1313113313") == 0 ) //this seems to be the most common 'correct' pattern on Type-C
-                || (strcmp (synctest10, "1113113313") == 0 ) //this seems to be the most common 'correct' pattern on Conventional
+                   (strcmp (synctest10, "1313113313") == 0 )
+                || (strcmp (synctest10, "1113113313") == 0 )
+                || (strcmp (synctest10, "1313113333") == 0 )
+                // || (strcmp (synctest10, "1113113333") == 0 )
+                // || (strcmp (synctest10, "1313133313") == 0 )
                )
             {
 

src/dsd_gps.c

@@ -129,8 +129,8 @@ void lip_protocol_decoder (dsd_opts * opts, dsd_state * state, uint8_t * input)
     if (opts->lrrp_file_output == 1)
     {
 
-      char * datestr = getDate();
-      char * timestr = getTime();
+      char * datestr = getDateS();
+      char * timestr = getTimeC();
 
       //open file by name that is supplied in the ncurses terminal, or cli
       pFile = fopen (opts->lrrp_out_file, "a");
@@ -247,8 +247,8 @@ void nmea_iec_61162_1 (dsd_opts * opts, dsd_state * state, uint8_t * input, uint
   if (opts->lrrp_file_output == 1)
   {
 
-    char * datestr = getDate();
-    char * timestr = getTime();
+    char * datestr = getDateS();
+    char * timestr = getTimeC();
 
     int s = (int)fkph; //rounded interger format for the log report
     int a = 0;
@@ -406,8 +406,8 @@ void harris_lptt (dsd_opts * opts, dsd_state * state, uint8_t * input, uint32_t
   if (opts->lrrp_file_output == 1 && src != 0 && gps_quality != 3)
   {
 
-    char * datestr = getDate();
-    char * timestr = getTime();
+    char * datestr = getDateS();
+    char * timestr = getTimeC();
 
     //rounded interger formats for the log report
     int s = (int)fkph;
@@ -536,8 +536,8 @@ void dmr_embedded_gps (dsd_opts * opts, dsd_state * state, uint8_t lc_bits[])
       if (opts->lrrp_file_output == 1)
       {
 
-        char * datestr = getDate();
-        char * timestr = getTime();
+        char * datestr = getDateS();
+        char * timestr = getTimeC();
 
         //open file by name that is supplied in the ncurses terminal, or cli
         pFile = fopen (opts->lrrp_out_file, "a");
@@ -644,8 +644,9 @@ void apx_embedded_gps (dsd_opts * opts, dsd_state * state, uint8_t lc_bits[])
       FILE * pFile; //file pointer
       if (opts->lrrp_file_output == 1)
       {
-        char * datestr = getDate();
-        char * timestr = getTime();
+
+        char * datestr = getDateS();
+        char * timestr = getTimeC();
 
         //open file by name that is supplied in the ncurses terminal, or cli
         pFile = fopen (opts->lrrp_out_file, "a");
@@ -719,11 +720,235 @@ void decode_ars(dsd_opts * opts, dsd_state * state, uint8_t * input, int len)
   UNUSED(len);
 }
 
+//WIP: Based on Denny's always brilliant reverse-engineering of GPS reports
 void nxdn_gps_report(dsd_opts * opts, dsd_state * state, uint8_t * input, uint32_t src)
 {
-  //TODO: This
-  UNUSED(opts);
-  UNUSED(state);
-  UNUSED(input);
-  UNUSED(src);
+
+  // Basic fields
+  // uint8_t quality    = (uint8_t)convert_bits_into_output(input+8, 4);   //can't seem to work these first two out correctly
+  // uint8_t num_sat    = (uint8_t)convert_bits_into_output(input+12, 4); //can't seem to work these first two out correctly
+  int16_t elevation  = (int16_t)convert_bits_into_output(input+56, 16);
+
+  // Speed & Heading (in tenths)
+  uint16_t speed_raw   = (uint16_t)convert_bits_into_output(input+74, 14);
+  uint16_t heading_raw = (uint16_t)convert_bits_into_output(input+92, 12);
+  double speed   = speed_raw   / 10.0; //knots or k/h
+  double heading = heading_raw / 10.0;
+
+  //Date
+  uint16_t year  = (uint16_t)(convert_bits_into_output(input+136,7) + 2000);
+  uint8_t  month = (uint8_t) convert_bits_into_output(input+143,4);
+  uint8_t  day   = (uint8_t)(convert_bits_into_output(input+147,5) + 1);
+
+  // Longitude (DDMM.mmmm format)
+  uint16_t lon_degmin = (uint16_t)convert_bits_into_output(input+152, 16);
+  uint16_t lon_frac   = (uint16_t)convert_bits_into_output(input+16, 15);
+  uint8_t  lon_hem    = (uint8_t) convert_bits_into_output(input+183, 1);
+  double lon_minutes = (lon_degmin % 100) + (lon_frac / 10000.0);
+  double lon_decimal = (lon_degmin / 100) + (lon_minutes / 60.0);
+  double longitude = (lon_hem == 0) ? lon_decimal : -lon_decimal;
+
+  // Latitude (DDMM.mmmm format)
+  uint16_t lat_degmin = (uint16_t)convert_bits_into_output(input+184,16);
+  uint16_t lat_frac   = (uint16_t)convert_bits_into_output(input+200,15);
+  uint8_t  lat_hem    = (uint8_t) convert_bits_into_output(input+215,1);
+  double lat_minutes = (lat_degmin % 100) + (lat_frac / 10000.0);
+  double lat_decimal = (lat_degmin / 100) + (lat_minutes / 60.0);
+  double latitude = (lat_hem == 0) ? lat_decimal : -lat_decimal;
+
+  //Time
+  // uint8_t hour   = (uint8_t) convert_bits_into_output(input+247,5);
+  // uint8_t minute = (uint8_t) convert_bits_into_output(input+252,6);
+  // uint8_t second = (uint8_t) convert_bits_into_output(input+258,6); //this seems to be zero, recheck time
+
+  char deg_glyph[4];
+  sprintf (deg_glyph, "%s", "°");
+
+  //Report
+  fprintf (stderr, "\n GPS: (%f%s, %f%s) ", latitude, deg_glyph, longitude, deg_glyph);
+  fprintf (stderr, "Speed: %lf k/h; ", speed);
+  fprintf (stderr, "COG: %lf; ", heading);
+  fprintf (stderr, "Elevation: %i; ", elevation);
+  // fprintf (stderr, "Quality: %d / %d; ", quality, num_sat);
+  fprintf (stderr, "Date: %04d/%02d/%02d ", year, month, day);
+  // fprintf (stderr, "Time: %02d:%02d:%02d ", hour, minute, second);
+
+  //save to LRRP report for mapping/logging
+  if (opts->lrrp_file_output == 1 && src != 0) //&& quality?
+  {
+
+    char * datestr = getDateS();
+    char * timestr = getTimeC();
+
+    //rounded interger formats for the log report
+    int s = (int)speed;
+    int a = (int)heading;
+
+    //open file by name that is supplied in the ncurses terminal, or cli
+    FILE * pFile; //file pointer
+    pFile = fopen (opts->lrrp_out_file, "a");
+    fprintf (pFile, "%s\t", datestr );
+    fprintf (pFile, "%s\t", timestr );
+    fprintf (pFile, "%08d\t", src);
+    fprintf (pFile, "%.6lf\t", latitude);
+    fprintf (pFile, "%.6lf\t", longitude);
+    fprintf (pFile, "%d\t ", s);
+    fprintf (pFile, "%d\t ", a);
+    fprintf (pFile, "\n");
+    fclose (pFile);
+
+    if (timestr != NULL)
+    {
+      free (timestr);
+      timestr = NULL;
+    }
+    if (datestr != NULL)
+    {
+      free (datestr);
+      datestr = NULL;
+    }
+
+  }
+
+  //reset source and target from PDU storage
+  state->dmr_lrrp_source[0] = 0;
+  state->dmr_lrrp_target[0] = 0;
+}
+
+uint8_t nmea_sentence_checker(dsd_opts * opts, dsd_state * state, uint8_t * input, uint8_t slot, int len)
+{
+
+  //Check Start and End, and Validity w/ Checksum
+  int i;
+  uint8_t start_value = (uint8_t)ConvertBitIntoBytes(input, 8);
+  uint8_t end_value = 0;
+  uint8_t checksum_calc = 0;
+  uint8_t checksum_ext = 0;
+  char checksum_str[3];
+  memset(checksum_str, 0, sizeof(checksum_str));
+  uint8_t valid = 0;
+
+  if (start_value == '$' || start_value == '!')
+  {
+    //debug
+    // fprintf (stderr, "Start Okay! ");
+
+    for (i = 1; i < len; i++)
+    {
+      uint8_t value = (uint8_t)ConvertBitIntoBytes(input+(i*8), 8);
+      if (value == '*')
+      {
+        end_value = value;
+        checksum_str[0] = (uint8_t)ConvertBitIntoBytes(input+(i*8)+8, 8);
+        checksum_str[1] = (uint8_t)ConvertBitIntoBytes(input+(i*8)+16, 8);
+        checksum_str[2] = 0;
+        sscanf (checksum_str, "%hhX", &checksum_ext);
+        break;
+      }
+      else if (value >= 0x20 && value < 0x7F)
+      {
+        checksum_calc ^= value;
+        continue;
+      }
+      else break; //anything else that isn't ascii range values
+    }
+
+    //debug
+    // if (end_value == '*')
+    //   fprintf (stderr, "Checksum Present! ");
+
+    if (checksum_ext == checksum_calc)
+    {
+      // fprintf (stderr, "Checksum Okay! (%02X / %02X)", checksum_calc, checksum_ext);
+      valid = 1;
+    }
+    else
+    {
+      // fprintf (stderr, "Checksum Err! (%02X / %02X) ", checksum_calc, checksum_ext);
+      valid = 0;
+    }
+      
+  }
+
+
+  //dump, if valid
+  memset(state->event_history_s[slot].Event_History_Items[0].text_message, 0, sizeof(state->event_history_s[slot].Event_History_Items[0].text_message));
+  if (valid)
+  {
+    uint8_t ascii = 0;
+    uint16_t crlf = 0;
+    for (i = 0; i < len; i++)
+    {
+      ascii = (uint8_t)ConvertBitIntoBytes(input+(i*8), 8);
+      crlf  = (uint16_t)ConvertBitIntoBytes(input+(i*8), 16);
+      if (ascii >= 0x20 && ascii < 0x7F)
+      {
+        fprintf (stderr, "%c", ascii);
+        state->event_history_s[slot].Event_History_Items[0].text_message[i] = ascii;
+      }
+      else if (crlf == 0x0D0A) //NMEA Sentences end with 0x0D 0x0A (CR/LF)
+      {
+        fprintf (stderr, "%s", " ");
+        state->event_history_s[slot].Event_History_Items[0].text_message[i+0] = 0x20; //Space
+        state->event_history_s[slot].Event_History_Items[0].text_message[i+1] = 0x20; //Space
+        i+=2;
+        break;
+      }
+      else break; //anything else that isn't ascii range values
+    }
+
+    //check for supplimentary string i.e., $PP25
+    ascii = (uint8_t)ConvertBitIntoBytes(input+(i*8), 8);
+    if (crlf == 0x0D0A && ascii == '$')
+    {
+      for (i = i; i < len; i++)
+      {
+        ascii = (uint8_t)ConvertBitIntoBytes(input+(i*8), 8);
+        crlf  = (uint16_t)ConvertBitIntoBytes(input+(i*8), 16);
+
+        if (ascii >= 0x20 && ascii < 0x7F)
+        {
+          fprintf (stderr, "%c", ascii);
+          state->event_history_s[slot].Event_History_Items[0].text_message[i] = ascii;
+        }
+        else if (crlf == 0x0D0A) //Supplimentary Sentences end with 0x0D 0x0A (CR/LF)
+        {
+          state->event_history_s[slot].Event_History_Items[0].text_message[i] = 0x20;
+          break;
+        }
+        else break; //anything else that isn't ascii range values
+      }
+
+    }
+
+    //debug
+    // fprintf(stderr, "\n %s", state->event_history_s[slot].Event_History_Items[0].text_message);
+
+    //dump to event history
+    state->event_history_s[slot].Event_History_Items[0].text_message[i] = '\0';
+    uint32_t source = state->dmr_lrrp_source[slot];
+    uint32_t target = state->dmr_lrrp_target[slot];
+    char comp_string[500]; memset (comp_string, 0, sizeof(comp_string));
+    sprintf (comp_string, "NMEA SRC: %d; TGT: %d;", source, target);
+    watchdog_event_datacall (opts, state, source, target, comp_string, slot);
+  }
+
+  else
+  {
+    if (start_value != '$' && start_value != '!')
+      fprintf (stderr, " Not an NMEA Sentence Structure;");
+    else if ( (start_value == '$' || start_value == '!') && end_value != '*')
+      fprintf (stderr, " Possible NMEA Sentence, Missing Ending *;");
+    else if (  start_value != '$' && start_value != '!' && end_value == '*')
+      fprintf (stderr, " Possible NMEA Sentence, Missing Starting $ or !;");
+    else if (checksum_calc != checksum_ext)
+      fprintf (stderr, " NMEA Checksum Error (%02X / %02X);", checksum_calc, checksum_ext);
+  }
+
+  //TODO: Convert to LRRP data and report / GPS on Event History
+
+  state->dmr_lrrp_source[slot] = 0;
+  state->dmr_lrrp_target[slot] = 0;
+
+  return valid;
 }

src/nxdn_element.c

@@ -186,6 +186,10 @@ void NXDN_Elements_Content_decode(dsd_opts * opts, dsd_state * state, uint8_t Cr
       //reset header validity
       state->data_header_valid[0] = 0;
 
+      //set source and target
+      state->dmr_lrrp_source[0] = 0;
+      state->dmr_lrrp_target[0] = 0;
+
       //reset encryption variables (for pdu)
       state->payload_algid = 0;
       state->payload_keyid = 0;
@@ -220,6 +224,10 @@ void NXDN_Elements_Content_decode(dsd_opts * opts, dsd_state * state, uint8_t Cr
       //reset header validity
       state->data_header_valid[0] = 0;
 
+      //set source and target
+      state->dmr_lrrp_source[0] = 0;
+      state->dmr_lrrp_target[0] = 0;
+
       //reset encryption variables (for pdu)
       state->payload_algid = 0;
       state->payload_keyid = 0;
@@ -712,23 +720,6 @@ void NXDN_decode_VCALL_ASSGN(dsd_opts * opts, dsd_state * state, uint8_t * Messa
         state->p25_vc_freq[0] = state->p25_vc_freq[1] = freq;
         opts->p25_is_tuned = 1; //set to 1 to set as currently tuned so we don't keep tuning nonstop
 
-        //set rid and tg when we actually tune to it
-        //only assign rid if not spare and not reserved (happens on private calls, unsure of its significance)
-        if ( (VoiceCallOption & 0xF) < 4) //ideally, only want 0, 2, or 3
-          state->nxdn_last_rid = SourceUnitID;
-        state->nxdn_last_tg = DestinationID;
-        sprintf (state->nxdn_call_type, "%s", NXDN_Call_Type_To_Str(CallType));
-
-        if (CallType == 3)
-        {
-          state->gi[0] = 1; //Private Call
-          //unassign these, sometimes, when trunking, these may be reversed by the time listened,
-          //and this will plant an extra private call in the event_history
-          state->nxdn_last_rid = 0;
-          state->nxdn_last_tg = 0;
-        }
-        else state->gi[0] = 0; //Group Call
-
         //Call String for Per Call WAV File
         sprintf (state->call_string[0], "%s", NXDN_Call_Type_To_Str(CallType));
         if (CCOption & 0x80) strcat (state->call_string[0], " Emergency");
@@ -760,23 +751,6 @@ void NXDN_decode_VCALL_ASSGN(dsd_opts * opts, dsd_state * state, uint8_t * Messa
         state->p25_vc_freq[0] = state->p25_vc_freq[1] = freq;
         opts->p25_is_tuned = 1;
 
-        //set rid and tg when we actually tune to it
-        //only assign rid if not spare and not reserved (happens on private calls, unsure of its significance)
-        if ( (VoiceCallOption & 0xF) < 4) //ideally, only want 0, 2, or 3
-          state->nxdn_last_rid = SourceUnitID;
-        state->nxdn_last_tg = DestinationID;
-        sprintf (state->nxdn_call_type, "%s", NXDN_Call_Type_To_Str(CallType));
-
-        if (CallType == 3)
-        {
-          state->gi[0] = 1; //Private Call
-          //unassign these, sometimes, when trunking, these may be reversed by the time listened,
-          //and this will plant an extra private call in the event_history
-          state->nxdn_last_rid = 0;
-          state->nxdn_last_tg = 0;
-        }
-        else state->gi[0] = 0; //Group Call
-
         //Call String for Per Call WAV File
         sprintf (state->call_string[0], "%s", NXDN_Call_Type_To_Str(CallType));
         if (CCOption & 0x80) strcat (state->call_string[0], " Emergency");
@@ -2586,6 +2560,10 @@ void nxdn_sdcall_header(dsd_opts * opts, dsd_state * state, uint8_t * Message)
 
   //set this is a valid header
   state->data_header_valid[0] = 1;
+
+  //set source and target
+  state->dmr_lrrp_source[0] = source;
+  state->dmr_lrrp_target[0] = target;
   
 }
 
@@ -2659,7 +2637,7 @@ void nxdn_dcall_header(dsd_opts * opts, dsd_state * state, uint8_t * Message)
   NXDN_Data_Call_Option_To_Str(dcall_opt, duplex_string, dcall_string);
 
   fprintf (stderr, "\n %s", KCYN);
-  fprintf (stderr, "Data Call Header (%04X) ", pkt_info);
+  fprintf (stderr, "Data Call Header (%06X) ", pkt_info);
   if (idas == 0)
     fprintf (stderr, "Source: %d; Target: %d; ", source, target);
   else
@@ -2732,6 +2710,10 @@ void nxdn_dcall_header(dsd_opts * opts, dsd_state * state, uint8_t * Message)
 
   //set this is a valid header
   state->data_header_valid[0] = 1;
+
+  //set source and target
+  state->dmr_lrrp_source[0] = source;
+  state->dmr_lrrp_target[0] = target;
   
 }
 
@@ -2739,8 +2721,9 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
 {
   UNUSED(opts);
 
-  //packet frame number and block number, observation shows these seem to be the same value (observed Type-D)
-  //but the manual does not quite explain these values indicate super packet of up to 16 big packets, and 1 packet is up to 16 blocks?
+  //if this is a full packet delivery, both of these numbers match typically,
+  //but if this is a selective retry resending blocks, the second number is the
+  //number of the retry block, and the first number is the remaining blocks
   uint8_t pf_num  = (uint8_t)ConvertBitIntoBytes(Message+8, 4);
   uint8_t blk_num = (uint8_t)ConvertBitIntoBytes(Message+12, 4);
 
@@ -2783,6 +2766,18 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
     return -1;
   }
 
+  //Part 1-B Basic Operation Ver.2.0 page 34
+  //if this is a retry, we don't have memory of the other pieces, so just nuke it
+  //although, I suppose its possible that, for example, there were originally 4 blocks,
+  //but the retry is going to retry 3,3,2,0 blocks all sequentially, or similar,
+  //and this would potentially miss it, but the CRC32 will determine success then.
+  if (pf_num != blk_num)
+  {
+    fprintf (stderr, "Partial Selective Retry, Previous Delivery Not Retained in Memory; ");
+    state->data_header_valid[0] = 0;
+    return -1;
+  }
+
   if (total_bytes < 4) //this shouldn't even happen in code
   {
     fprintf (stderr, "Total Bytes After Padding Less Than Required; ");
@@ -2797,7 +2792,7 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
   memcpy(state->dmr_pdu_sf[0]+ptr, Message+16, byte_len*8*sizeof(uint8_t));
 
   //Finished Assembly
-  if (blk_num == 0)
+  if (pf_num == 0)
   {
 
     //KS creation and application, if applicable
@@ -2933,18 +2928,13 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
     if (crc_ext == crc_chk)
     {
       uint8_t opcode = (uint8_t)ConvertBitIntoBytes(state->dmr_pdu_sf[0], 8);
+      uint8_t nmea = (uint8_t)ConvertBitIntoBytes(state->dmr_pdu_sf[0]+8, 8);
       uint32_t reverse = (uint8_t)ConvertBitIntoBytes(state->dmr_pdu_sf[0], 24); //observed 3 bytes of zeroes
-      if (opcode == 0x06)
+      if (opcode == 0x06 && (nmea == '$' || nmea == '!')) //may only need to check one of the other
       {
-        //String Data Dump if first byte is 0x06 (NMEA sentences observed here)
+        //Check NMEA Sentence
         fprintf (stderr, "\n ");
-        for (int i = 1; i < total_bytes; i++)
-        {
-          uint8_t ascii = (uint8_t)ConvertBitIntoBytes(state->dmr_pdu_sf[0]+(i*8), 8);
-          if (ascii >= 0x20 && ascii < 0x7F)
-            fprintf (stderr, "%c", ascii);
-          else break;
-        }
+        nmea_sentence_checker(opts, state, state->dmr_pdu_sf[0]+8, 0, total_bytes);
       }
       else if (reverse == 0)
       {
@@ -2962,7 +2952,7 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
 
         //Debug Data Dump
         fprintf (stderr, "\n  REV: ");
-        for (int i = 0; i < total_bytes-4-4+1; i++) //sans the CRC and the leading zeroes
+        for (int i = 0; i < total_bytes-7; i++) //sans the CRC and the leading zeroes
           fprintf (stderr, "%02X", reverse_bytes[i]);
 
         uint8_t reverse_byte_bits[total_bytes*8];
@@ -2971,7 +2961,7 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
 
         //GPS report on 0xFFFC? or is that just any odd Kenwood message?
         if ((uint16_t)convert_bits_into_output(reverse_byte_bits, 16) == 0xFFFC)
-          nxdn_gps_report(opts, state, reverse_byte_bits+16, state->nxdn_last_rid); //src is probably reset on cac
+          nxdn_gps_report(opts, state, reverse_byte_bits+16, state->dmr_lrrp_source[0]);
 
       }
       else
@@ -3000,6 +2990,10 @@ int nxdn_dcall_data(dsd_opts * opts, dsd_state * state, int type, uint8_t * Mess
     //reset header validity
     state->data_header_valid[0] = 0;
 
+    //set source and target
+    state->dmr_lrrp_source[0] = 0;
+    state->dmr_lrrp_target[0] = 0;
+
     //reset encryption variables
     state->payload_algid = 0;
     state->payload_keyid = 0;

src/p25p1_pdu_data.c

@@ -457,8 +457,18 @@ void p25_decode_pdu_data(dsd_opts * opts, dsd_state * state, uint8_t * input, in
     if (sap == 0 || sap == 4) //User Data or Packet Data (both are UDP typically, same format dmr UDP/IP data)
       decode_ip_pdu (opts, state, len+1, input+ptr);
 
-    else if (sap == 48) //Tier 1 Location Service (or does it depend on the io bit?)
-      utf8_to_text(state, 1, len-ptr+1, input+ptr); //TODO, read initial string, i.e., $GPRMC and properly decode
+    //NMEA Tier 1 Location Reporting w/ Supplimentary $PP25 string
+    else if (sap == 48)
+    {
+      len += 12; //not sure how we ended up off by up to 12 on this, above negation too much?
+      state->dmr_lrrp_source[state->currentslot] = state->lastsrc;
+      state->dmr_lrrp_source[state->currentslot] = state->lasttg;
+      uint8_t input_bits[(len+1)*8];
+      memset(input_bits, 0, sizeof(input_bits));
+      unpack_byte_array_into_bit_array(input, input_bits, len);
+      fprintf (stderr, "\n ");
+      nmea_sentence_checker(opts, state, input_bits+ptr*8, state->currentslot, len*8);
+    }
 
     // else //default catch all (debug only)
     // {