AFG/dump1090
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Don't attempt to error correct DF-11

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Don't attempt to error correct DF-11, because we can't be sure that the
checksum/crc is supposed to be 0.

Also a few typo's corrected
This commit is contained in:
Malcolm Robb 2013-04-15 21:55:46 +01:00
parent bb20d0b5b8
commit bdf985a792
1 changed files with 5 additions and 6 deletions
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11
dump1090.c
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@ -52,11 +52,11 @@
// File Version number // File Version number
// ==================== // ====================
// Format is : MajorVer.MinorVer.DayMonth.Year" // Format is : MajorVer.MinorVer.DayMonth.Year"
// MajorVer chances only with significant changes // MajorVer changes only with significant changes
// MinorVer changes when additional features are added, but not for bug fixes (range 00-99) // MinorVer changes when additional features are added, but not for bug fixes (range 00-99)
// DayDate & Year changes for all changes, including for bug fixes. It represent the release date of the update // DayDate & Year changes for all changes, including for bug fixes. It represent the release date of the update
// //
#define MODES_DUMP1090_VERSION "1.00.1404.13" #define MODES_DUMP1090_VERSION "1.00.1504.13"
#define MODES_DEFAULT_RATE 2000000 #define MODES_DEFAULT_RATE 2000000
#define MODES_DEFAULT_FREQ 1090000000 #define MODES_DEFAULT_FREQ 1090000000
@ -389,7 +389,7 @@ void modesInit(void) {
// The most this could be is if I&Q are both 128 (or 127 or 127.5), so you could end up with a magnitude // The most this could be is if I&Q are both 128 (or 127 or 127.5), so you could end up with a magnitude
// of 181.019 (or 179.605, or 180.312) // of 181.019 (or 179.605, or 180.312)
// //
// However, in reality the magnitude of the signal should never exceed the range -1 to +1, becaure the // However, in reality the magnitude of the signal should never exceed the range -1 to +1, because the
// values are I = rCos(w) and Q = rSin(w). Therefore the integer computed magnitude should (can?) never // values are I = rCos(w) and Q = rSin(w). Therefore the integer computed magnitude should (can?) never
// exceed 128 (or 127, or 127.5 or whatever) // exceed 128 (or 127, or 127.5 or whatever)
// //
@ -1052,13 +1052,12 @@ void decodeModesMessage(struct modesMessage *mm, unsigned char *msg) {
else else
{mm->crcok = (mm->iid == 0);} {mm->crcok = (mm->iid == 0);}
if (!mm->crcok && Modes.fix_errors && if (!mm->crcok && Modes.fix_errors && (mm->msgtype == 17))
(mm->msgtype == 11 || mm->msgtype == 17))
{ {
if ((mm->errorbit = fixSingleBitErrors(msg,mm->msgbits)) != -1) { if ((mm->errorbit = fixSingleBitErrors(msg,mm->msgbits)) != -1) {
mm->crc = modesChecksum(msg,mm->msgbits); mm->crc = modesChecksum(msg,mm->msgbits);
mm->crcok = 1; mm->crcok = 1;
} else if (Modes.aggressive && mm->msgtype == 17 && } else if (Modes.aggressive &&
(mm->errorbit = fixTwoBitsErrors(msg,mm->msgbits)) != -1) (mm->errorbit = fixTwoBitsErrors(msg,mm->msgbits)) != -1)
{ {
mm->crc = modesChecksum(msg,mm->msgbits); mm->crc = modesChecksum(msg,mm->msgbits);