[hamradio-commits] [dump1090] 110/389: Change Squawk/ModeA code
Matthew Ernisse
mernisse-guest at moszumanska.debian.org
Wed Nov 5 00:19:45 UTC 2014
This is an automated email from the git hooks/post-receive script.
mernisse-guest pushed a commit to branch master
in repository dump1090.
commit 25f92e54ba3ffb5f842482220dfccf97a05f2e1d
Author: Malcolm Robb <Support at ATTAvionics.com>
Date: Thu Apr 25 23:22:34 2013 +0100
Change Squawk/ModeA code
The original code stores the squawk as a decimal (base 10) value. Change
this to a hex value to reduce the amount of maths required to convert
the input binary value..
Rename all the variables used to store the squawk to "modeA", rather
than variously identity, squawk and modeA.
---
dump1090.c | 92 +++++++++++++++++++++++++++++---------------------------------
1 file changed, 43 insertions(+), 49 deletions(-)
diff --git a/dump1090.c b/dump1090.c
index dc0d4f5..476f6f9 100644
--- a/dump1090.c
+++ b/dump1090.c
@@ -142,6 +142,7 @@ struct aircraft {
int track; /* Angle of flight. */
time_t seen; /* Time at which the last packet was received. */
long messages; /* Number of Mode S messages received. */
+ int modeA; /* Squawk */
int modeC; /* Altitude */
long modeAcount; /* Mode A Squawk hit Count */
long modeCcount; /* Mode C Altitude hit Count */
@@ -155,7 +156,6 @@ struct aircraft {
double lat, lon; /* Coordinated obtained from CPR encoded data. */
int sbsflags;
uint64_t odd_cprtime, even_cprtime;
- int squawk;
struct aircraft *next; /* Next aircraft in our linked list. */
};
@@ -284,7 +284,7 @@ struct modesMessage {
int fs; /* Flight status for DF4,5,20,21 */
int dr; /* Request extraction of downlink request. */
int um; /* Request extraction of downlink request. */
- int identity; /* 13 bits identity (Squawk). */
+ int modeA; /* 13 bits identity (Squawk). */
// DF32 ModeA & Mode C
int modeC; /* Decoded Mode C */
@@ -1056,11 +1056,8 @@ void decodeModeAMessage(struct modesMessage *mm, int ModeA)
// Use an upper address byte of FF, since this is ICAO unallocated
mm->addr = 0x00FF0000 | (ModeA & 0x0000FF7F);
- // Set the Identity field to decimal ModeA
- mm->identity = (ModeA & 7)
- + (((ModeA >> 4) & 7) * 10)
- + (((ModeA >> 8) & 7) * 100)
- + (((ModeA >> 12) & 7) * 1000);
+ // Set the Identity field to ModeA
+ mm->modeA = ModeA & 0x7777;
// Flag ident in flight status
mm->fs = ModeA & 0x0080;
@@ -1494,31 +1491,31 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
* from 0 to 7.
*
* The actual meaning is just 4 octal numbers, but we convert it
- * into a base ten number tha happens to represent the four
+ * into a hex number tha happens to represent the four
* octal numbers.
*
* For more info: http://en.wikipedia.org/wiki/Gillham_code */
{
- int decIdentity = 0;
- unsigned char rawIdentity;
+ int hexSquawk = 0;
+ unsigned char rawSquawk;
- rawIdentity = msg[2];
- if (rawIdentity & 0x01) {decIdentity += 40;} // C4
- if (rawIdentity & 0x02) {decIdentity += 2000;} // A2
- if (rawIdentity & 0x04) {decIdentity += 20;} // C2
- if (rawIdentity & 0x08) {decIdentity += 1000;} // A1
- if (rawIdentity & 0x10) {decIdentity += 10;} // C1
+ rawSquawk = msg[2];
+ if (rawSquawk & 0x01) {hexSquawk |= 0x0040;} // C4
+ if (rawSquawk & 0x02) {hexSquawk |= 0x2000;} // A2
+ if (rawSquawk & 0x04) {hexSquawk |= 0x0020;} // C2
+ if (rawSquawk & 0x08) {hexSquawk |= 0x1000;} // A1
+ if (rawSquawk & 0x10) {hexSquawk |= 0x0010;} // C1
- rawIdentity = msg[3];
- if (rawIdentity & 0x01) {decIdentity += 4;} // D4
- if (rawIdentity & 0x02) {decIdentity += 400;} // B4
- if (rawIdentity & 0x04) {decIdentity += 2;} // D2
- if (rawIdentity & 0x08) {decIdentity += 200;} // B2
- if (rawIdentity & 0x10) {decIdentity += 1;} // D1
- if (rawIdentity & 0x20) {decIdentity += 100;} // B1
- if (rawIdentity & 0x80) {decIdentity += 4000;} // A4
+ rawSquawk = msg[3];
+ if (rawSquawk & 0x01) {hexSquawk |= 0x0004;} // D4
+ if (rawSquawk & 0x02) {hexSquawk |= 0x0400;} // B4
+ if (rawSquawk & 0x04) {hexSquawk |= 0x0002;} // D2
+ if (rawSquawk & 0x08) {hexSquawk |= 0x0200;} // B2
+ if (rawSquawk & 0x10) {hexSquawk |= 0x0001;} // D1
+ if (rawSquawk & 0x20) {hexSquawk |= 0x0100;} // B1
+ if (rawSquawk & 0x80) {hexSquawk |= 0x4000;} // A4
- mm->identity = decIdentity;
+ mm->modeA = hexSquawk;
}
/* DF 11 & 17: try to populate our ICAO addresses whitelist.
@@ -1678,7 +1675,7 @@ void displayModesMessage(struct modesMessage *mm) {
printf(" Flight Status : %s\n", fs_str[mm->fs]);
printf(" DR : %d\n", mm->dr);
printf(" UM : %d\n", mm->um);
- printf(" Squawk : %d\n", mm->identity);
+ printf(" Squawk : %x\n", mm->modeA);
printf(" ICAO Address : %06x\n", mm->addr);
if (mm->msgtype == 21) {
@@ -1688,7 +1685,7 @@ void displayModesMessage(struct modesMessage *mm) {
/* DF 11 */
printf("DF 11: All Call Reply.\n");
printf(" Capability : %s\n", ca_str[mm->ca]);
- printf(" ICAO Address %06x\n", mm->addr);
+ printf(" ICAO Address: %06x\n", mm->addr);
if (mm->iid > 16)
{printf(" IID : SI-%02d\n", mm->iid-16);}
else
@@ -1743,11 +1740,11 @@ void displayModesMessage(struct modesMessage *mm) {
// DF 32 is special code we use for Mode A/C
printf("SSR : Mode A/C Reply.\n");
if (mm->fs & 0x0080) {
- printf(" Mode A : %04d IDENT\n", mm->identity);
+ printf(" Mode A : %04x IDENT\n", mm->modeA);
} else {
- printf(" Mode A : %04d\n", mm->identity);
+ printf(" Mode A : %04x\n", mm->modeA);
if (mm->altitude >= -1300)
- {printf(" Mode C : %d feet\n",mm->altitude);}
+ {printf(" Mode C : %d feet\n", mm->altitude);}
}
} else {
@@ -2160,7 +2157,6 @@ struct aircraft *interactiveCreateAircraft(struct modesMessage *mm) {
a->addr = mm->addr;
a->flight[0] = '\0';
- a->altitude = 0;
a->speed = 0;
a->track = 0;
a->odd_cprlat = 0;
@@ -2174,11 +2170,12 @@ struct aircraft *interactiveCreateAircraft(struct modesMessage *mm) {
a->sbsflags = 0;
a->seen = time(NULL);
a->messages = 0;
- a->squawk = 0;
- a->modeACflags = 0;
+ a->modeACflags = 0;
+ a->modeA = 0;
+ a->modeC = 0;
+ a->altitude = 0;
a->modeAcount = 0;
a->modeCcount = 0;
- a->modeC = 0;
a->next = NULL;
return (a);
}
@@ -2225,16 +2222,15 @@ void interactiveUpdateAircraftModeA(struct aircraft *a) {
if ((b->modeACflags & MODEAC_MSG_FLAG) == 0) {// skip any fudged ICAO records
// First check for Mode-A <=> Mode-S Squawk matches
- if (a->squawk == b->squawk) { // If a 'real' Mode-S ICAO exists using this Mode-A Squawk
+ if (a->modeA == b->modeA) { // If a 'real' Mode-S ICAO exists using this Mode-A Squawk
b->modeAcount++;
if ( (b->modeAcount > 0) &&
((b->modeCcount > 1) || (a->modeC < -12)) )
- {a->modeACflags |= MODEAC_MSG_MODES_HIT;} // flag this ModeA/C probably belongs to a known Mode S
+ {a->modeACflags |= MODEAC_MSG_MODES_HIT;} // flag this ModeA/C probably belongs to a known Mode S
}
// Next check for Mode-C <=> Mode-S Altitude matches
- if (a->modeC == b->modeC) // If a 'real' Mode S ICAO exists at this Mode-C Altitude
- {
+ if (a->modeC == b->modeC) { // If a 'real' Mode S ICAO exists at this Mode-C Altitude
b->modeCcount++;
if ((b->modeAcount > 0) && (b->modeCcount > 1))
{a->modeACflags |= MODEAC_MSG_MODES_HIT;} // flag this ModeA/C probably belongs to a known Mode S
@@ -2499,10 +2495,10 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) {
a->altitude = mm->altitude;
a->modeC = mm->modeC;
} else if(mm->msgtype == 5 || mm->msgtype == 21) {
- if (a->squawk != mm->identity) {
+ if (a->modeA != mm->modeA) {
a->modeAcount = 0; // Squawk has changed, so zero the hit count
}
- a->squawk = mm->identity;
+ a->modeA = mm->modeA;
} else if (mm->msgtype == 17) {
if (mm->metype >= 1 && mm->metype <= 4) {
memcpy(a->flight, mm->flight, sizeof(a->flight));
@@ -2539,7 +2535,7 @@ struct aircraft *interactiveReceiveData(struct modesMessage *mm) {
}
} else if(mm->msgtype == 32) {
a->modeACflags = MODEAC_MSG_FLAG;
- a->squawk = mm->identity;
+ a->modeA = mm->modeA;
a->modeC = mm->modeC;
a->altitude = mm->altitude;
interactiveUpdateAircraftModeA(a);
@@ -2593,8 +2589,8 @@ void interactiveShowData(void) {
altitude = -9999;
}
- if (a->squawk > 0 && a->squawk <= 7777) {
- sprintf(squawk, "%04d", a->squawk);
+ if (a->modeA) {
+ sprintf(squawk, "%04x", a->modeA);
}
if (msgs > 99999) {
@@ -2875,10 +2871,8 @@ void modesSendSBSOutput(struct modesMessage *mm, struct aircraft *a) {
struct tm stTime;
if (mm->msgtype == 4 || mm->msgtype == 5 || mm->msgtype == 21) {
- /* Node: identity is calculated/kept in base10 but is actually
- * octal (07500 is represented as 7500) */
- if (mm->identity == 7500 || mm->identity == 7600 ||
- mm->identity == 7700) emergency = -1;
+ if (mm->modeA == 0x7500 || mm->modeA == 0x7600 ||
+ mm->modeA == 0x7700) emergency = -1;
if (mm->fs == 1 || mm->fs == 3) ground = -1;
if (mm->fs == 2 || mm->fs == 3 || mm->fs == 4) alert = -1;
if (mm->fs == 4 || mm->fs == 5) spi = -1;
@@ -2916,7 +2910,7 @@ void modesSendSBSOutput(struct modesMessage *mm, struct aircraft *a) {
p += sprintf(p, "MSG,5,%s,,%d,,,,,,,%d,%d,%d,%d", strCommon, mm->altitude, alert, emergency, spi, ground);
} else if (mm->msgtype == 5) {
- p += sprintf(p, "MSG,6,%s,,,,,,,,%d,%d,%d,%d,%d", strCommon, mm->identity, alert, emergency, spi, ground);
+ p += sprintf(p, "MSG,6,%s,,,,,,,,%x,%d,%d,%d,%d", strCommon, mm->modeA, alert, emergency, spi, ground);
} else if (mm->msgtype == 11) {
p += sprintf(p, "MSG,8,%s,,,,,,,,,,,,", strCommon);
@@ -2938,7 +2932,7 @@ void modesSendSBSOutput(struct modesMessage *mm, struct aircraft *a) {
p += sprintf(p, "MSG,4,%s,,,%d,%d,,,%i,,0,0,0,0", strCommon, mm->velocity, mm->heading, vr);
} else if (mm->msgtype == 21) {
- p += sprintf(p, "MSG,6,%s,,,,,,,,%d,%d,%d,%d,%d", strCommon, mm->identity, alert, emergency, spi, ground);
+ p += sprintf(p, "MSG,6,%s,,,,,,,,%x,%d,%d,%d,%d", strCommon, mm->modeA, alert, emergency, spi, ground);
} else {
return;
--
Alioth's /usr/local/bin/git-commit-notice on /srv/git.debian.org/git/pkg-hamradio/dump1090.git
More information about the pkg-hamradio-commits
mailing list