[wip] fix: dsc & dse parsing with kaitai

dsc_dse.ksy

@@ -0,0 +1,128 @@
+meta:
+  id: dsc_dse
+seq:
+  - id: start_sentence
+    type: str
+    size: 1
+    encoding: UTF-8 
+  - id: talker_id
+    type: str
+    size: 2
+    encoding: UTF-8 
+  - id: sentence_id
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: format_specifier
+    doc: |
+      Format Specifier (without first digit)
+      102 = selective call to a group of ships in particular geographic area
+      112 = distress alert call
+      114 = selective call to a group of ships having common interest
+      116 = all ships call
+      120 = selective call to particular individual station
+      123 = selective call to a particular individual using automatic service
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: sender_mssi
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8
+  - id: category_specifier
+    doc: |
+       Category Element (without first digit)
+       100 = Routine
+       108 = Safety
+       110 = Urgency
+       112 = Distress
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: category_field_1
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: category_field_2
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: sender_position
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: time_utc
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: vessel_mmsi
+    doc: |
+      Vessel MMSI in a relayed distress
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: unknown_1
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: unknown_2
+    type: str
+    terminator: 44 # ,
+    encoding: UTF-8 
+  - id: expansion_follows
+    type: str
+    terminator: 42 # ,
+    encoding: UTF-8
+  - id: checksum
+    type: str
+    size: 2
+    encoding: UTF-8
+  - id: continuation
+    type:
+      switch-on: expansion_follows
+      cases:
+        '"E"': expansion
+types:
+  expansion:
+    seq:
+      - id: start_sentence
+        type: str
+        size: 1
+        encoding: UTF-8 
+      - id: talker_id
+        type: str
+        size: 2
+        encoding: UTF-8 
+      - id: sentence_id
+        type: str
+        terminator: 44 # ,
+        encoding: UTF-8 
+      - id: message_id
+        type: str
+        terminator: 44
+        encoding: UTF-8
+      - id: message_count
+        type: str
+        terminator: 44
+        encoding: UTF-8
+      - id: unknown
+        type: str
+        terminator: 44
+        encoding: UTF-8
+      - id: sender_mmsi
+        type: str
+        terminator: 44
+        encoding: UTF-8
+      - id: expansion_data_specifier
+        type: str
+        terminator: 44
+        encoding: UTF-8
+      - id: payload
+        type: str
+        terminator: 42
+        encoding: UTF-8
+      - id: checksum
+        type: str
+        size: 2
+        encoding: UTF-8
+

test/dsc_alert.txt

@@ -0,0 +1,2 @@
+$CDDSC,12,5031105200,,05,00,2380814428,1800,,,R,E*6C
+$CDDSE,1,1,A,5031105200,04,19252411*18

test/dsc_position_report.txt

@@ -0,0 +1,2 @@
+$CDDSC,20,5031105200,08,21,26,2380814428,1800,,,B,E*77
+$CDDSE,1,1,A,5031105200,04,19252411*18

test/dsc_relayed_alert.txt

@@ -0,0 +1,2 @@
+$CDDSC,16,2350763930,12,12,00,2380814428,1800,5031105200,05,S,E*65
+$CDDSE,1,1,A,5031105200,04,19252411*18