From 735429b87a32181f1de1b1b0cde8b86709d54e47 Mon Sep 17 00:00:00 2001 From: Malcolm Robb Date: Thu, 9 May 2013 18:48:07 +0100 Subject: [PATCH] Additional bFlags for Lat/Lon decoding Additional flags in the bFlags variables for even and odd CPR lat/lon updates. Change the interactiveReceiveData function to use the bFlags when updating the aircraft (a) structure from the newly received (mm) message structure. This should hopefully be faster than basically re-decoding the DF, type and subtypes all over again. If we decode the lat/lon into the aircraft (a) structure, back populate it into the message (mm) structure. This allows us to print a decoded Lat/Lon in the decoded message list output. --- dump1090.c | 157 +++++++++++++++++++++++++++-------------------------- 1 file changed, 79 insertions(+), 78 deletions(-) diff --git a/dump1090.c b/dump1090.c index 67976d5..f6aad6f 100644 --- a/dump1090.c +++ b/dump1090.c @@ -105,7 +105,7 @@ #define MODES_USER_LATLON_VALID (1<<0) -#define MODES_ACFLAGS_LATLON_VALID (1<<0) // Aircraft Lat/Lon is known +#define MODES_ACFLAGS_LATLON_VALID (1<<0) // Aircraft Lat/Lon is decoded #define MODES_ACFLAGS_ALTITUDE_VALID (1<<1) // Aircraft altitude is known #define MODES_ACFLAGS_HEADING_VALID (1<<2) // Aircraft heading is known #define MODES_ACFLAGS_SPEED_VALID (1<<3) // Aircraft speed is known @@ -115,8 +115,13 @@ #define MODES_ACFLAGS_EWSPEED_VALID (1<<7) // Aircraft East West Speed is known #define MODES_ACFLAGS_NSSPEED_VALID (1<<8) // Aircraft North South Speed is known #define MODES_ACFLAGS_AOG (1<<9) // Aircraft is On the Ground +#define MODES_ACFLAGS_LLEVEN_VALID (1<<10) // Aircraft Even Lot/Lon is known +#define MODES_ACFLAGS_LLODD_VALID (1<<11) // Aircraft Odd Lot/Lon is known #define MODES_ACFLAGS_LATLON_REL_OK (1<<15) // Indicates it's OK to do a relative CPR +#define MODES_ACFLAGS_LLEITHER_VALID (MODES_ACFLAGS_LLEVEN_VALID | MODES_ACFLAGS_LLODD_VALID) +#define MODES_ACFLAGS_LLBOTH_VALID (MODES_ACFLAGS_LLEVEN_VALID | MODES_ACFLAGS_LLODD_VALID) + #define MODES_SBS_LAT_LONG_FRESH (1<<0) #define MODES_DEBUG_DEMOD (1<<0) @@ -296,6 +301,8 @@ struct modesMessage { int heading; // Reported by aircraft, or computed from from EW and NS velocity int raw_latitude; // Non decoded latitude. int raw_longitude; // Non decoded longitude. + double fLat; // Coordinates obtained from CPR encoded data if/when decoded + double fLon; // Coordinates obtained from CPR encoded data if/when decoded char flight[16]; // 8 chars flight number. int ew_velocity; // E/W velocity. int ns_velocity; // N/S velocity. @@ -1511,6 +1518,8 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) { } else if (metype >= 5 && metype <= 18) { // Position Message mm->raw_latitude = ((msg[6] & 3) << 15) | (msg[7] << 7) | (msg[8] >> 1); mm->raw_longitude = ((msg[8] & 1) << 16) | (msg[9] << 8) | (msg[10]); + mm->bFlags |= (mm->msg[6] & 0x04) ? MODES_ACFLAGS_LLODD_VALID + : MODES_ACFLAGS_LLEVEN_VALID; if (metype >= 9) { // Airborne int AC12Field = ((msg[5] << 4) | (msg[6] >> 4)) & 0x0FFF; if (AC12Field) {// Only attempt to decode if a valid (non zero) altitude is present @@ -1704,8 +1713,7 @@ void displayModesMessage(struct modesMessage *mm) { } } - } else if (mm->msgtype == 11) { - /* DF 11 */ + } else if (mm->msgtype == 11) { // DF 11 printf("DF 11: All Call Reply.\n"); printf(" Capability : %s\n", ca_str[mm->ca]); printf(" ICAO Address: %06x\n", mm->addr); @@ -1736,8 +1744,13 @@ void displayModesMessage(struct modesMessage *mm) { printf(" F flag : %s\n", (mm->msg[6] & 0x04) ? "odd" : "even"); printf(" T flag : %s\n", (mm->msg[6] & 0x08) ? "UTC" : "non-UTC"); printf(" Altitude : %d feet\n", mm->altitude); - printf(" Latitude : %d (not decoded)\n", mm->raw_latitude); - printf(" Longitude: %d (not decoded)\n", mm->raw_longitude); + if (mm->bFlags & MODES_ACFLAGS_LATLON_VALID) { + printf(" Latitude : %f\n", mm->fLat); + printf(" Longitude: %f\n", mm->fLon); + } else { + printf(" Latitude : %d (not decoded)\n", mm->raw_latitude); + printf(" Longitude: %d (not decoded)\n", mm->raw_longitude); + } } else if (mm->metype == 19) { // Airborne Velocity if (mm->mesub == 1 || mm->mesub == 2) { @@ -2252,14 +2265,11 @@ struct aircraft *interactiveCreateAircraft(struct modesMessage *mm) { if (mm->msgtype == 32) { int modeC = ModeAToModeC(mm->modeA | mm->fs); a->modeACflags = MODEAC_MSG_FLAG; - a->modeA = mm->modeA; - a->bFlags = mm->bFlags; if (modeC < -12) { a->modeACflags |= MODEAC_MSG_MODEA_ONLY; } else { - a->modeC = modeC; - a->altitude = modeC * 100; - a->bFlags |= MODES_ACFLAGS_ALTITUDE_VALID; + mm->altitude = modeC * 100; + mm->bFlags |= MODES_ACFLAGS_ALTITUDE_VALID; } } return (a); @@ -2604,7 +2614,13 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) { a->timestamp = mm->timestampMsg; a->messages++; - if (mm->msgtype == 0 || mm->msgtype == 4 || mm->msgtype == 20) { + // If a (new) CALLSIGN has been received, copy it to the aircraft structure + if (mm->bFlags & MODES_ACFLAGS_CALLSIGN_VALID) { + memcpy(a->flight, mm->flight, sizeof(a->flight)); + } + + // If a (new) ALTITUDE has been received, copy it to the aircraft structure + if (mm->bFlags & MODES_ACFLAGS_ALTITUDE_VALID) { if ( (a->modeCcount) // if we've a modeCcount already && (a->altitude != mm->altitude ) ) // and Altitude has changed // && (a->modeC != mm->modeC + 1) // and Altitude not changed by +100 feet @@ -2613,81 +2629,70 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) { a->modeCcount = 0; //....zero the hit count a->modeACflags &= ~MODEAC_MSG_MODEC_HIT; } - a->altitude = mm->altitude; + a->altitude = mm->altitude; a->modeC = (mm->altitude + 49) / 100; + } - if ((mm->msgtype == 20) && (mm->msg[4] == 0x20)) { - memcpy(a->flight, mm->flight, sizeof(a->flight)); - } - - } else if(mm->msgtype == 5 || mm->msgtype == 21) { + // If a (new) SQUAWK has been received, copy it to the aircraft structure + if (mm->bFlags & MODES_ACFLAGS_SQUAWK_VALID) { if (a->modeA != mm->modeA) { a->modeAcount = 0; // Squawk has changed, so zero the hit count a->modeACflags &= ~MODEAC_MSG_MODEA_HIT; } a->modeA = mm->modeA; + } - if ((mm->msgtype == 21) && (mm->msg[4] == 0x20)) { - memcpy(a->flight, mm->flight, sizeof(a->flight)); + // If a (new) HEADING has been received, copy it to the aircraft structure + if (mm->bFlags & MODES_ACFLAGS_HEADING_VALID) { + a->track = mm->heading; + } + + // If a (new) SPEED has been received, copy it to the aircraft structure + if (mm->bFlags & MODES_ACFLAGS_SPEED_VALID) { + a->speed = mm->velocity; + } + + // if the Aircraft has landed or taken off since the last message, clear the even/odd CPR flags + if ((a->bFlags ^ mm->bFlags) & MODES_ACFLAGS_AOG) { + a->bFlags &= ~(MODES_ACFLAGS_LLBOTH_VALID | MODES_ACFLAGS_AOG); + + } else if ( (mm->bFlags & MODES_ACFLAGS_LLEITHER_VALID) + && (((mm->bFlags | a->bFlags) & MODES_ACFLAGS_LLEITHER_VALID) == MODES_ACFLAGS_LLBOTH_VALID) ) { + // If it's a new even/odd raw lat/lon, and we now have both even and odd,decode the CPR + int fflag; + + if (mm->bFlags & MODES_ACFLAGS_LLODD_VALID) { + fflag = 1; + a->odd_cprlat = mm->raw_latitude; + a->odd_cprlon = mm->raw_longitude; + a->odd_cprtime = mstime(); + } else { + fflag = 0; + a->even_cprlat = mm->raw_latitude; + a->even_cprlon = mm->raw_longitude; + a->even_cprtime = mstime(); } - - } else if (mm->msgtype == 17) { - if (mm->metype >= 1 && mm->metype <= 4) { - memcpy(a->flight, mm->flight, sizeof(a->flight)); - - } else if (mm->metype >= 5 && mm->metype <= 18) { - int fflag = mm->msg[6] & 0x04; - - if ((a->bFlags ^ mm->bFlags) & MODES_ACFLAGS_AOG) { - a->odd_cprtime = a->even_cprtime = 0; // Change airborne = change CPR scale need new pair - a->bFlags ^= MODES_ACFLAGS_AOG; // Ground = metype 5-8, Airborne = metype 9-18 - } - - if (mm->metype >= 9) { // Airborne - if ( (a->modeCcount) // if we've a modeCcount already - && (a->altitude != mm->altitude ) ) // and Altitude has changed -// && (a->modeC != mm->modeC + 1) // and Altitude not changed by +100 feet -// && (a->modeC + 1 != mm->modeC ) ) // and Altitude not changes by -100 feet - { - a->modeCcount = 0; //....zero the hit count - a->modeACflags &= ~MODEAC_MSG_MODEC_HIT; - } - a->altitude = mm->altitude; - a->modeC = (mm->altitude + 49) / 100; - } else { // Ground - a->speed = mm->velocity; - a->track = mm->heading; - } - - if (fflag) { - a->odd_cprlat = mm->raw_latitude; - a->odd_cprlon = mm->raw_longitude; - a->odd_cprtime = mstime(); - } else { - a->even_cprlat = mm->raw_latitude; - a->even_cprlon = mm->raw_longitude; - a->even_cprtime = mstime(); - } - // Try relative CPR first - if (decodeCPRrelative(a, fflag, (mm->bFlags & MODES_ACFLAGS_AOG))) { - // If it fails then try global if the two data are less than 10 seconds apart, compute - // the position. - if (abs((int)(a->even_cprtime - a->odd_cprtime)) <= 10000) { - decodeCPR(a, fflag, (mm->bFlags & MODES_ACFLAGS_AOG)); - } - } - - } else if (mm->metype == 19) { - if ((mm->mesub >= 1) && (mm->mesub <= 4)) { - a->speed = mm->velocity; - a->track = mm->heading; + // Try relative CPR first + if (decodeCPRrelative(a, fflag, (mm->bFlags & MODES_ACFLAGS_AOG))) { + // If it fails then try global if the two data are less than 10 seconds apart + if (abs((int)(a->even_cprtime - a->odd_cprtime)) <= 10000) { + decodeCPR(a, fflag, (mm->bFlags & MODES_ACFLAGS_AOG)); } } - } else if(mm->msgtype == 32) { + //If we sucessfully decoded, back copy the results to mm so that we can print them in list output + if (a->bFlags & MODES_ACFLAGS_LATLON_VALID) { + mm->bFlags |= MODES_ACFLAGS_LATLON_VALID; + mm->fLat = a->lat; + mm->fLon = a->lon; + } + } + // Update the aircrafts a->bFlags to reflect the newly received mm->bFlags; + a->bFlags |= mm->bFlags; + + if (mm->msgtype == 32) { int flags = a->modeACflags; - if ((flags & (MODEAC_MSG_MODEC_HIT | MODEAC_MSG_MODEC_OLD)) == MODEAC_MSG_MODEC_OLD) { // // This Mode-C doesn't currently hit any known Mode-S, but it used to because MODEAC_MSG_MODEC_OLD is @@ -2702,13 +2707,9 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) { a->modeACflags = flags & ~MODEAC_MSG_MODEC_OLD; a->messages = 1; } - - if (a->bFlags & MODES_ACFLAGS_ALTITUDE_VALID) { - mm->altitude = a->altitude; - mm->bFlags |= MODES_ACFLAGS_ALTITUDE_VALID; - } } - return a; + + return (a); } /* Show the currently captured interactive data on screen. */