updates to handler

pyModeS/decoder/common.py

@@ -31,7 +31,7 @@ def np2bin(npbin):
 def df(msg):
     """Decode Downlink Format vaule, bits 1 to 5."""
     msgbin = hex2bin(msg)
-    return bin2int(msgbin[0:5])
+    return min( bin2int(msgbin[0:5]) , 24 )
 
 
 def crc(msg, encode=False):

pyModeS/extra/tcpclient.py

@@ -146,64 +146,84 @@ class BaseClient(Thread):
 
     def read_skysense_buffer(self):
         """
+        ----------------------------------------------------------------------------------
+        Field      SS MS MS MS MS MS MS MS MS MS MS MS MS MS MS TS TS TS TS TS TS RS RS RS
+        ----------------------------------------------------------------------------------
+        Position:   0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
+        ----------------------------------------------------------------------------------
+        Example:   24 8d 4c a5 c0 20 24 22 f1 28 38 20 f3 24 04 be 8d 0d d8 e0 80 66 ed b9
+        Example:   24 5d 3c 48 c8 ad 3d f9 00 00 00 00 00 00 00 be 8d 66 c4 c5 7c 4c d7 2d
+        
+        
+        SS field - Start character
+        Position 0:
+          1 byte = 8 bits
+          Start character '$'
+        
+        MS field - Payload
+        Postion 1 through 14:
+          14 bytes = 112 bits
+          Mode-S payload
+          In case of DF types that only carry 7 bytes of information position 8 through 14 are set to 0x00.
+          Decoding of payload information is not within the scope of this document.
+        
+        TS field - Time stamp
+        Position 15 through 20:
+          6 bytes = 48 bits
+          Time stamp with fields as:
+        
+            Lock Status - Status of internal time keeping mechanism
+            Equal to 1 if operating normally
+            Bit 47 - 1 bit
+        
+            Time of day in UTC seconds, between 0 and 86399
+            Bits 46 through 30 - 17 bits
+            
+            Nanoseconds into current second, between 0 and 999999999
+            Bits 29 through 0 - 30 bits
+        
+        
+        RS field - Signal Level
+        Position 21 through 23:
+         3 bytes = 24 bits
+         RSSI (received signal strength indication) and relative noise level with fields
+        
+         RNL, Q12.4 unsigned fixed point binary with 4 fractional bits and 8 integer bits.
+         This is and indication of the noise level of the message. Roughly 40 counts per 10dBm.
+         Bits 23 through 12 - 12 bits 
+        
+         RSSI, Q12.4 unsigned fixed point binary with 4 fractional bits and 8 integer bits.
+         This is an indication of the signal level of the received message in ADC counts. Roughly 40 counts per 10dBm.
+         Bits 11 through 0 - 12 bits   
+        """
+        SS_MSGLENGTH = 24
 
-----------------------------------------------------------------------------------
+        SS_STARTCHAR = 0x24
-Field      SS MS MS MS MS MS MS MS MS MS MS MS MS MS MS TS TS TS TS TS TS RS RS RS
-----------------------------------------------------------------------------------
-Position:   0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
-----------------------------------------------------------------------------------
-Example:   24 8d 4c a5 c0 20 24 22 f1 28 38 20 f3 24 04 be 8d 0d d8 e0 80 66 ed b9
-Example:   24 5d 3c 48 c8 ad 3d f9 00 00 00 00 00 00 00 be 8d 66 c4 c5 7c 4c d7 2d
-
-
-SS field - Start character
-Position 0:
-  1 byte = 8 bits
-  Start character '$'
-
-MS field - Payload
-Postion 1 through 14:
-  14 bytes = 112 bits
-  Mode-S payload
-  In case of DF types that only carry 7 bytes of information position 8 through 14 are set to 0x00.
-  Decoding of payload information is not within the scope of this document.
-
-TS field - Time stamp
-Position 15 through 20:
-  6 bytes = 48 bits
-  Time stamp with fields as:
-
-    Lock Status - Status of internal time keeping mechanism
-    Equal to 1 if operating normally
-    Bit 47 - 1 bit
-
-    Time of day in UTC seconds, between 0 and 86399
-    Bits 46 through 30 - 17 bits
-    
-    Nanoseconds into current second, between 0 and 999999999
-    Bits 29 through 0 - 30 bits
-
-
-RS field - Signal Level
-Position 21 through 23:
- 3 bytes = 24 bits
- RSSI (received signal strength indication) and relative noise level with fields
-
- RNL, Q12.4 unsigned fixed point binary with 4 fractional bits and 8 integer bits.
- This is and indication of the noise level of the message. Roughly 40 counts per 10dBm.
- Bits 23 through 12 - 12 bits 
-
- RSSI, Q12.4 unsigned fixed point binary with 4 fractional bits and 8 integer bits.
- This is an indication of the signal level of the received message in ADC counts. Roughly 40 counts per 10dBm.
- Bits 11 through 0 - 12 bits
-
- """
-
         messages = []
         msg = []
         i = 0
         while i < len(self.buffer):
-            if self.buffer[i] == 0x24:
+            if self.buffer[i] == SS_STARTCHAR:
+                i += 1
+                if (self.buffer[i]>>7):
+                    #Long message
+                    payload = self.buffer[i:i+14]
+                else:
+                    #Short message
+                    payload = self.buffer[i:i+7]
+
+                msg = ''.join('%02X' % i for i in payload)
+
+                i += 14
+
+                tsbin = self.buffer[i:i+6]
+                sec = (tsbin[0] << 10) | (tsbin[1] << 2) | (tsbin[2] >> 6)
+                nano = (tsbin[2] << 24) | (tsbin[3] << 16) | (tsbin[4] << 8) | tsbin[5]
+                ts = sec + nano*1.0e-9
+                i += 6
+                #Signal level - Don't care
+                i += 3
+                messages.append( [msg,ts] )