Parser and printer for type 20 and TCAS info

python/modes_flightgear.py

@@ -72,7 +72,7 @@ class modes_flightgear(modes_parse.modes_parse):
         if complete:
             print "FG update: %s" % (self.callsigns[icao24][0])
             msg = fg_posmsg(self.callsigns[icao24][0],
-                            None,#TODO FIX should populate ac type; this isn't pressing bc it appears nobody populates this field
+                            self.callsigns[icao24][1],
                             self.positions[icao24][0],
                             self.positions[icao24][1],
                             self.positions[icao24][2],
@@ -133,14 +133,14 @@ modelmap = { None:                       'Aircraft/777-200/Models/777-200ER.xml'
 }
 
 class fg_posmsg(fg_header):
-    def __init__(self, callsign, model, lat, lon, alt, hdg, vel, vs, turnrate):
+    def __init__(self, callsign, modelname, lat, lon, alt, hdg, vel, vs, turnrate):
         #from the above, calculate valid FGFS mp vals
         #this is the translation layer between ADS-B and FGFS
         fg_header.__init__(self)
         self.callsign = callsign
         if self.callsign is None:
             self.callsign = "UNKNOWN"
-        self.modelname = model
+        self.modelname = modelname
         if self.modelname not in modelmap:
             #this should keep people on their toes when strange aircraft types are seen
             self.model = 'Aircraft/santa/Models/santa.xml'

python/modes_parse.py

@@ -72,38 +72,9 @@ class data_field:
       #return the bits as a number
       return bits
 
-#type MB (extended squitter types 20,21) subfields
-class mb_reply(data_field):
-  fields = { "acs": (45,20), "ais": (41,48),  "ara": (41,14), "bcs": (65,16),
-             "bds": (33,8),  "bds1": (33,4),  "bds2": (37,4), "cfs": (41,4),
-             "ecs": (81,8),  "mte": (60,1),   "rac": (55,4),  "rat": (59,1),
-             "tid": (33,26), "tida": (63,13), "tidb": (83,6), "tidr": (76,7),
-             "tti": (61,2)
-           }
-  offset = 33 #fields offset by 33 to match documentation
-
-  #types are based on bds1 subfield
-  types = { 0: ["bds", "bds1", "bds2"], #TODO
-            1: ["bds", "bds1", "bds2", "cfs", "acs", "bcs"],
-            2: ["bds", "bds1", "bds2", "ais"],
-            3: ["bds", "bds1", "bds2", "ara",  "rac", "rat",
-                "mte", "tti",  "tida", "tidr", "tidb"]
-          }
-
-  def get_type(self):
-    bds1 = self.get_bits(self.fields["bds1"])
-    bds2 = self.get_bits(self.fields["bds2"])
-    if bds1 not in (0,1,2,3) or bds2 not in (0,):
-      raise NoHandlerError
-    return int(bds1)
-
-  def get_numbits(self):
-    return 56
-
 class bds09_reply(data_field):
   offset = 6
-  types = {
+  types = {  #BDS0,9 subtype 0
-             #BDS0,9 subtype 0
              0: {"sub": (6,3), "dew": (10,1), "vew": (11,11), "dns": (22,1),
                  "vns": (23,11), "str": (34,1), "tr": (35,6), "dvr": (41,1),
                  "vr": (42,9)},
@@ -164,8 +135,47 @@ class me_reply(data_field):
   def get_numbits(self):
     return 56
 
+#resolves the TCAS reply types from TTI info
+class tcas_reply(data_field):
+  offset = 61
+  types = { 0: {"tti": (61,2)}, #UNKNOWN
+            1: {"tti": (61,2), "tid": (63,26)},
+            2: {"tti": (61,2), "tida": (63,13), "tidr": (76,7), "tidb": (83,6)}
+          }
+  def get_type(self):
+    return self.get_bits(61,2)
+
+  def get_numbits(self):
+    return 28
+
+#extended squitter types 20,21 MB subfield
+class mb_reply(data_field):
+  offset = 33 #fields offset by 33 to match documentation
+  #types are based on bds1 subfield
+  types = { 0: {"bds1": (33,4), "bds2": (37,4)}, #TODO
+            1: {"bds1": (33,4), "bds2": (37,4), "cfs": (41,4), "acs": (45,20), "bcs": (65,16), "ecs": (81,8)},
+            2: {"bds1": (33,4), "bds2": (37,4), "ais": (41,48)},
+            3: {"bds1": (33,4), "bds2": (37,4), "ara": (41,14), "rac": (55,4), "rat": (59,1),
+                "mte": (60,1), "tcas": (61, 28, tcas_reply)}
+          }
+
+  def get_type(self):
+    bds1 = self.get_bits(33,4)
+    bds2 = self.get_bits(37,4)
+    if bds1 not in (0,1,2,3) or bds2 not in (0,):
+      raise NoHandlerError
+    return int(bds1)
+
+  def get_numbits(self):
+    return 56
+
+#  #type MV (extended squitter type 16) subfields
+#  mv_fields = { "ara": (41,14), "mte": (60,1),  "rac": (55,4), "rat": (59,1),
+#                "vds": (33,8),  "vds1": (33,4), "vds2": (37,4)
+#              }
+
+#the whole Mode S packet type
 class modes_reply(data_field):
-  #bitfield definitions according to Mode S spec for each packet type
   types = { 0: {"df": (1,5), "vs": (6,1), "cc": (7,1), "sl": (9,3), "ri": (14,4), "ac": (20,13), "ap": (33,24)},
             4: {"df": (1,5), "fs": (6,3), "dr": (9,5), "um": (14,6), "ac": (20,13), "ap": (33,24)},
             5: {"df": (1,5), "fs": (6,3), "dr": (9,5), "um": (14,6), "id": (20,13), "ap": (33,24)},
@@ -186,11 +196,6 @@ class modes_reply(data_field):
   def get_type(self):
     return self.get_bits(1,5)
 
-#  #type MV (extended squitter type 16) subfields
-#  mv_fields = { "ara": (41,14), "mte": (60,1),  "rac": (55,4), "rat": (59,1),
-#                "vds": (33,8),  "vds1": (33,4), "vds2": (37,4)
-#              }
-
 class modes_parse:
   def __init__(self, mypos):
       self.my_location = mypos
@@ -330,28 +335,42 @@ class modes_parse:
                    "NO COMMUNICATIONS", "UNLAWFUL INTERFERENCE", "RESERVED", "RESERVED"]
     return eps_strings[data["me"]["eps"]]
 
-#  def parse20(self, shortdata, longdata):
+  def parseMB_id(self, data): #bds1 == 2, bds2 == 0
-#    [fs, dr, um, alt] = self.parse4(shortdata)
+    msg = ""
-#    #BDS defines TCAS reply type and is the first 8 bits
+    for i in range(0, 8):
-#    #BDS1 is first four, BDS2 is bits 5-8
+      msg += self.charmap( data["mb"]["ais"] >> (42-6*i) & 0x3F)
-#    bds1 = longdata_bits(longdata, 33, 4)
+    return (msg)
-#    bds2 = longdata_bits(longdata, 37, 4)
-#    #bds2 != 0 defines extended TCAS capabilities, not in spec
-#    return [fs, dr, um, alt, bds1, bds2]
 
-#  def parseMB_commB(self, longdata): #bds1, bds2 == 0
+  def parseMB_TCAS_resolutions(self, data):
-#    raise NoHandlerError
+    #these are LSB because the ICAO are asshats
+    ara_bits    = {41: "CLIMB", 42: "DON'T DESCEND", 43: "DON'T DESCEND >500FPM", 44: "DON'T DESCEND >1000FPM",
+                   45: "DON'T DESCEND >2000FPM", 46: "DESCEND", 47: "DON'T CLIMB", 48: "DON'T CLIMB >500FPM",
+                   49: "DON'T CLIMB >1000FPM", 50: "DON'T CLIMB >2000FPM", 51: "TURN LEFT", 52: "TURN RIGHT",
+                   53: "DON'T TURN LEFT", 54: "DON'T TURN RIGHT"}
+    rac_bits    = {55: "DON'T DESCEND", 56: "DON'T CLIMB", 57: "DON'T TURN LEFT", 58: "DON'T TURN RIGHT"}
+    ara = data["mb"]["ara"]
+    #check to see which bits are set
+    resolutions = ""
+    for bit, name in ara_bits:
+      if ara & (1 << (54-bit)):
+        resolutions += " " + name
+    complements = ""
+    for bit, name in rac_bits:
+      if rac & (1 << (58-bit)):
+        complements += " " + name
+    return (resolutions, complements)
 
-#  def parseMB_caps(self, longdata): #bds1 == 1, bds2 == 0
+  #rat is 1 if resolution advisory terminated <18s ago
-#    #cfs, acs, bcs
+  #mte is 1 if multiple threats indicated
-#    raise NoHandlerError
+  #tti is threat type: 1 if ID, 2 if range/brg/alt
+  #tida is threat altitude in Mode C format
+  def parseMB_TCAS_threatid(self, data): #bds1==3, bds2==0, TTI==1
+    #3: {"bds1": (33,4), "bds2": (37,4), "ara": (41,14), "rac": (55,4), "rat": (59,1),
+    #    "mte": (60,1), "tti": (61,2),  "tida": (63,13), "tidr": (76,7), "tidb": (83,6)}
+    (resolutions, complements) = self.parseMB_TCAS_resolutions(data)
+    return (resolutions, complements, data["mb"]["rat"], data["mb"]["mte"], data["mb"]["tcas"]["tid"])
 
-#  def parseMB_id(self, longdata): #bds1 == 2, bds2 == 0
+  def parseMB_TCAS_threatloc(self, data): #bds1==3, bds2==0, TTI==2
-#    msg = ""
+    (resolutions, complements) = self.parseMB_TCAS_resolutions(data)
-#    for i in range(0, 8):
+    threat_alt = decode_alt(data["mb"]["tcas"]["tida"], True)
-#      msg += self.charmap( longdata >> (42-6*i) & 0x3F)
+    return (resolutions, complements, data["mb"]["rat"], data["mb"]["mte"], threat_alt, data["mb"]["tcas"]["tidr"], data["mb"]["tcas"]["tidb"])
-#    return (msg)
-
-#  def parseMB_TCASRA(self, longdata): #bds1 == 3, bds2 == 0
-    #ara[41-54],rac[55-58],rat[59],mte[60],tti[61-62],tida[63-75],tidr[76-82],tidb[83-88]
-#    raise NoHandlerError

python/modes_print.py

@@ -174,3 +174,39 @@ class modes_output_print(modes_parse.modes_parse):
       retstr = "Type 17 subtype %i from %x not implemented" % (subtype, icao24)
 
     return retstr
+
+  def print20(self, data, ecc):
+    [fs, dr, um, alt] = self.parse4(data)
+    mb_fields = data["mb"].get_fields()
+    bds1 = mb_fields["bds1"]
+    bds2 = mb_fields["bds2"]
+
+    if bds2 != 0:
+      retstr = "No handler for BDS2 == %i from %x" % (bds2, ecc)
+
+    elif bds1 == 0:
+      retstr = "No handler for BDS1 == 0 from %x" % ecc
+    elif bds1 == 1:
+      retstr = "Type 20 link capability report from %x: ACS: 0x%x, BCS: 0x%x, ECS: 0x%x, continues %i" \
+                % (ecc, mb_fields["acs"], mb_fields["bcs"], mb_fields["ecs"], mb_fields["cfs"])
+    elif bds1 == 2:
+      retstr = "Type 20 identification from %x with text %s" % (ecc, self.parseMB_id(data))
+    elif bds2 == 3:
+      retstr = "TCAS report from %x: " % ecc
+      tti = mb_fields["tcas"].get_type()
+      if tti == 1:
+        (resolutions, complements, rat, mte, threat_id) = self.parseMB_TCAS_threatid(data)
+        retstr += "threat ID: %x advised: %s complement: %s" % (threat_id, resolutions, complements)
+      elif tti == 2:
+        (resolutions, complements, rat, mte, threat_alt, threat_range, threat_bearing) = self.parseMB_TCAS_threatloc(data)
+        retstr += "range: %i bearing: %i alt: %i advised: %s complement: %s" % (threat_range, threat_bearing, threat_alt, resolutions, complements)
+      else:
+        retstr += " (no handler for TTI=%i)" % tti
+      if mte == 1:
+        retstr += " (multiple threats)"
+      if rat == 1:
+        retstr += " (resolved)"
+    else:
+      retstr = "No handler for BDS1 == %i from %x" % (bds1, ecc)
+      
+    return retstr