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Decode DF-18

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This commit is contained in:
Malcolm Robb 2013-05-22 00:05:03 +01:00
parent 08ffc3f541
commit 4a3113f65a
1 changed files with 89 additions and 6 deletions
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93
dump1090.c
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@ -296,7 +296,7 @@ struct modesMessage {
int ca; // Responder capabilities int ca; // Responder capabilities
int iid; int iid;
// DF 17 // DF 17, DF 18
int metype; // Extended squitter message type. int metype; // Extended squitter message type.
int mesub; // Extended squitter message subtype. int mesub; // Extended squitter message subtype.
int heading; // Reported by aircraft, or computed from from EW and NS velocity int heading; // Reported by aircraft, or computed from from EW and NS velocity
@ -1653,6 +1653,18 @@ char *ca_str[8] = {
/* 7 */ "Level 7 ???" /* 7 */ "Level 7 ???"
}; };
// DF 18 Control field table.
char *cf_str[8] = {
/* 0 */ "ADS-B ES/NT device with ICAO 24-bit address",
/* 1 */ "ADS-B ES/NT device with other address",
/* 2 */ "Fine format TIS-B",
/* 3 */ "Coarse format TIS-B",
/* 4 */ "TIS-B managment message",
/* 5 */ "TIS-B relay of ADS-B message with other address",
/* 6 */ "ADS-B rebroadcast using DF-17 message format",
/* 7 */ "Reserved"
};
/* Flight status table. */ /* Flight status table. */
char *fs_str[8] = { char *fs_str[8] = {
/* 0 */ "Normal, Airborne", /* 0 */ "Normal, Airborne",
@ -1710,7 +1722,7 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
mm->phase_corrected = 0; mm->phase_corrected = 0;
mm->crc = modesChecksum(msg, mm->msgbits); mm->crc = modesChecksum(msg, mm->msgbits);
if ((mm->crc) && (Modes.fix_errors) && (mm->msgtype == 17)) { if ((mm->crc) && (Modes.fix_errors) && ((mm->msgtype == 17) || (mm->msgtype == 18))) {
// if ((mm->crc) && (Modes.fix_errors) && ((mm->msgtype == 11) || (mm->msgtype == 17))) { // if ((mm->crc) && (Modes.fix_errors) && ((mm->msgtype == 11) || (mm->msgtype == 17))) {
// //
// Fixing single bit errors in DF-11 is a bit dodgy because we have no way to // Fixing single bit errors in DF-11 is a bit dodgy because we have no way to
@ -1738,6 +1750,7 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
mm->crcok = (mm->crc < 80); mm->crcok = (mm->crc < 80);
mm->iid = mm->crc; mm->iid = mm->crc;
mm->addr = (msg[1] << 16) | (msg[2] << 8) | (msg[3]); mm->addr = (msg[1] << 16) | (msg[2] << 8) | (msg[3]);
mm->ca = (msg[0] & 0x07); // Responder capabilities
if (0 == mm->crc) { if (0 == mm->crc) {
// DF 11 : if crc == 0 try to populate our ICAO addresses whitelist. // DF 11 : if crc == 0 try to populate our ICAO addresses whitelist.
@ -1747,12 +1760,23 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
} else if (mm->msgtype == 17) { // DF 17 } else if (mm->msgtype == 17) { // DF 17
mm->crcok = (mm->crc == 0); mm->crcok = (mm->crc == 0);
mm->addr = (msg[1] << 16) | (msg[2] << 8) | (msg[3]); mm->addr = (msg[1] << 16) | (msg[2] << 8) | (msg[3]);
mm->ca = (msg[0] & 0x07); // Responder capabilities
if (0 == mm->crc) { if (0 == mm->crc) {
// DF 17 : if crc == 0 try to populate our ICAO addresses whitelist. // DF 17 : if crc == 0 try to populate our ICAO addresses whitelist.
addRecentlySeenICAOAddr(mm->addr); addRecentlySeenICAOAddr(mm->addr);
} }
} else if (mm->msgtype == 18) { // DF 18
mm->crcok = (mm->crc == 0);
mm->addr = (msg[1] << 16) | (msg[2] << 8) | (msg[3]);
mm->ca = (msg[0] & 0x07); // Control Field
if (0 == mm->crc) {
// DF 18 : if crc == 0 try to populate our ICAO addresses whitelist.
addRecentlySeenICAOAddr(mm->addr);
}
} else { // All other DF's } else { // All other DF's
// Compare the checksum with the whitelist of recently seen ICAO // Compare the checksum with the whitelist of recently seen ICAO
// addresses. If it matches one, then declare the message as valid // addresses. If it matches one, then declare the message as valid
@ -1771,7 +1795,6 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
// Fields for DF11, DF17 // Fields for DF11, DF17
if (mm->msgtype == 11 || mm->msgtype == 17) { if (mm->msgtype == 11 || mm->msgtype == 17) {
mm->ca = msg[0] & 0x07; // Responder capabilities
if (mm->ca == 4) { if (mm->ca == 4) {
mm->bFlags |= MODES_ACFLAGS_AOG_VALID | MODES_ACFLAGS_AOG; mm->bFlags |= MODES_ACFLAGS_AOG_VALID | MODES_ACFLAGS_AOG;
} else if (mm->ca == 5) { } else if (mm->ca == 5) {
@ -1810,8 +1833,9 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
} }
} }
// Fields for DF17 squitter // Fields for DF17, DF18_CF0, DF18_CF1, DF18_CF6 squitters
if (mm->msgtype == 17) { if ( (mm->msgtype == 17)
|| ((mm->msgtype == 18) && ((mm->ca == 0) || (mm->ca == 1) || (mm->ca == 6)) )) {
int metype = mm->metype = msg[4] >> 3; // Extended squitter message type int metype = mm->metype = msg[4] >> 3; // Extended squitter message type
int mesub = mm->mesub = msg[4] & 7; // Extended squitter message subtype int mesub = mm->mesub = msg[4] & 7; // Extended squitter message subtype
@ -2104,6 +2128,65 @@ void displayModesMessage(struct modesMessage *mm) {
} else if (mm->msgtype == 18) { // DF 18 } else if (mm->msgtype == 18) { // DF 18
printf("DF 18: Extended Squitter.\n"); printf("DF 18: Extended Squitter.\n");
printf(" Control Field : %d (%s)\n", mm->ca, cf_str[mm->ca]);
if ((mm->ca == 0) || (mm->ca == 1) || (mm->ca == 6)) {
if (mm->ca == 1) {
printf(" Other Address : %06x\n", mm->addr);
} else {
printf(" ICAO Address : %06x\n", mm->addr);
}
printf(" Extended Squitter Type: %d\n", mm->metype);
printf(" Extended Squitter Sub : %d\n", mm->mesub);
printf(" Extended Squitter Name: %s\n", getMEDescription(mm->metype, mm->mesub));
// Decode the extended squitter message
if (mm->metype >= 1 && mm->metype <= 4) { // Aircraft identification
printf(" Aircraft Type : %c%d\n", ('A' + 4 - mm->metype), mm->mesub);
printf(" Identification : %s\n", mm->flight);
//} else if (mm->metype >= 5 && mm->metype <= 8) { // Surface position
} else if (mm->metype >= 9 && mm->metype <= 18) { // Airborne position Baro
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);
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) {
printf(" EW status : %s\n", (mm->bFlags & MODES_ACFLAGS_EWSPEED_VALID) ? "Valid" : "Unavailable");
printf(" EW velocity : %d\n", mm->ew_velocity);
printf(" NS status : %s\n", (mm->bFlags & MODES_ACFLAGS_NSSPEED_VALID) ? "Valid" : "Unavailable");
printf(" NS velocity : %d\n", mm->ns_velocity);
printf(" Vertical status : %s\n", (mm->bFlags & MODES_ACFLAGS_VERTRATE_VALID) ? "Valid" : "Unavailable");
printf(" Vertical rate src : %d\n", ((mm->msg[8] >> 4) & 1));
printf(" Vertical rate : %d\n", mm->vert_rate);
} else if (mm->mesub == 3 || mm->mesub == 4) {
printf(" Heading status : %s\n", (mm->bFlags & MODES_ACFLAGS_HEADING_VALID) ? "Valid" : "Unavailable");
printf(" Heading : %d\n", mm->heading);
printf(" Airspeed status : %s\n", (mm->bFlags & MODES_ACFLAGS_SPEED_VALID) ? "Valid" : "Unavailable");
printf(" Airspeed : %d\n", mm->velocity);
printf(" Vertical status : %s\n", (mm->bFlags & MODES_ACFLAGS_VERTRATE_VALID) ? "Valid" : "Unavailable");
printf(" Vertical rate src : %d\n", ((mm->msg[8] >> 4) & 1));
printf(" Vertical rate : %d\n", mm->vert_rate);
} else {
printf(" Unrecognized ME subtype: %d subtype: %d\n", mm->metype, mm->mesub);
}
//} else if (mm->metype >= 20 && mm->metype <= 22) { // Airborne position GNSS
} else {
printf(" Unrecognized ME type: %d subtype: %d\n", mm->metype, mm->mesub);
}
}
} else if (mm->msgtype == 19) { // DF 19 } else if (mm->msgtype == 19) { // DF 19
printf("DF 19: Military Extended Squitter.\n"); printf("DF 19: Military Extended Squitter.\n");