ubxtool: More GPS Subframe 1, 4 and 5 decode.

A long ways to go...

1 files changed, 154 insertions, 8 deletions

diff --git a/ubxtool b/ubxtool
index 3d7b6eda..0c4e8a18 100755
--- a/ubxtool
+++ b/ubxtool
@@ -3213,6 +3213,17 @@ class ubx(object):
 
         return s
 
+    # decode GPS subframe 5, pages 1 to 24,
+    # and subframe 4, pages 2 to 5, and 7 to 10
+    def almanac(self, words):
+        """Decode GPS Almanac"""
+        s = "    Almanac"
+        # s += ("\n   dataid %u svid %u theta %d\n" %
+        #       (words[2] >> 28,
+        #        (words[2] >> 22) & 0x3f),
+        #        (words[2] >> 6 & 0xff))
+        return s
+
     cnav_msgids = {
         10: "Ephemeris 1",
         11: "Ephemeris 2",
@@ -3230,6 +3241,84 @@ class ubx(object):
         37: "Clock & Midi Almanac",
         }
 
+    # map subframe 4 SV ID to Page number
+    sbfr4_svid_page = {
+        57: 1,
+        25: 2,
+        26: 3,
+        27: 4,
+        28: 5,
+        57: 6,
+        29: 7,
+        30: 8,
+        31: 9,
+        32: 10,
+        57: 11,
+        62: 12,
+        52: 13,
+        53: 14,
+        54: 15,
+        57: 16,
+        55: 17,
+        56: 18,
+        58: 19,
+        59: 20,
+        57: 21,
+        60: 22,
+        61: 23,
+        62: 24,
+        63: 25,
+        }
+
+    # map subframe 5 SV ID to Page number
+    sbfr5_svid_page = {
+        1: 1,
+        2: 2,
+        3: 3,
+        4: 4,
+        5: 5,
+        6: 6,
+        7: 7,
+        8: 8,
+        9: 9,
+        10: 10,
+        11: 11,
+        21: 12,
+        13: 13,
+        14: 14,
+        15: 15,
+        16: 16,
+        17: 17,
+        18: 18,
+        19: 19,
+        20: 20,
+        21: 21,
+        22: 22,
+        23: 23,
+        24: 24,
+        51: 25,
+        }
+
+    # URA Index to URA meters
+    ura_meters = {
+        0: "2.40 m",
+        1: "3.40 m",
+        2: "4.85 m",
+        3: "6.85 m",
+        4: "9.65 m",
+        5: "13.65 m",
+        6: "24.00 m",
+        7: "48.00 m",
+        8: "96.00 m",
+        9: "192.00 m",
+        10: "384.00 m",
+        11: "768.00 m",
+        12: "1536.00 m",
+        13: "3072.00 m",
+        14: "6144.00 m",
+        15: "Unk",
+        }
+
     def rxm_sfrbx(self, buf):
         """UBX-RXM-SFRBX decode, Broadcast Navigation Data Subframe"""
 
@@ -3277,22 +3366,79 @@ class ubx(object):
                            subframe))
 
                     if 1 == subframe:
-                        s += ("\n   WN %u\n" %
-                              (words[2] >> 20))
+                        ura = (words[2] >> 14) & 0x0f
+                        s += ("\n   WN %u C/A on L2 %u URA %u (%s) SVH %#x\n" %
+                              (words[2] >> 20,
+                               (words[2] >> 18) & 0x03,
+                               ura, index_s(ura, self.ura_meters),
+                               (words[2] >> 8) & 0x3f))
+
                     elif 2 == subframe:
                         s += ("\n   IODE %u\n" %
                               (words[2] >> 22))
+
                     elif 3 == subframe:
                         s += ("\n   Cic %u\n" %
                               (words[2] >> 14))
+
                     elif 4 == subframe:
-                        s += ("\n   dataid %u svid %u\n" %
-                              (words[2] >> 28,
-                               (words[2] >> 22) & 0x3f))
+                        # all data in subfraaem 4 is "reserved",
+                        # except for pages 13, 18, 15
+                        # as of 2018, dataid is always 1.
+                        svid = (words[2] >> 22) & 0x3f
+                        page = index_s(svid, self.sbfr4_svid_page)
+                        s += ("\n   dataid %u svid %u (page %s)\n" %
+                              (words[2] >> 28, svid, page))
+
+                        if (((2 <= page and 5 >= page) or
+                             (5 <= page and 10 >= page))):
+                            s += self.almanac(words)
+                        elif 13 == page:
+                            s += "    NWCT"
+                        elif 17 == page:
+                            s += ("    Special messages: " +
+                                  chr((words[2] >> 14) & 0xff) +
+                                  chr((words[2] >> 6) & 0xff) +
+                                  chr((words[3] >> 22) & 0xff) +
+                                  chr((words[3] >> 14) & 0xff) +
+                                  chr((words[3] >> 6) & 0xff) +
+                                  chr((words[4] >> 22) & 0xff) +
+                                  chr((words[4] >> 14) & 0xff) +
+                                  chr((words[4] >> 6) & 0xff) +
+                                  chr((words[5] >> 22) & 0xff) +
+                                  chr((words[5] >> 14) & 0xff) +
+                                  chr((words[5] >> 6) & 0xff) +
+                                  chr((words[6] >> 22) & 0xff) +
+                                  chr((words[6] >> 14) & 0xff) +
+                                  chr((words[6] >> 6) & 0xff) +
+                                  chr((words[7] >> 22) & 0xff) +
+                                  chr((words[7] >> 14) & 0xff) +
+                                  chr((words[7] >> 6) & 0xff) +
+                                  chr((words[8] >> 22) & 0xff) +
+                                  chr((words[8] >> 14) & 0xff) +
+                                  chr((words[8] >> 6) & 0xff) +
+                                  chr((words[9] >> 22) & 0xff) +
+                                  chr((words[9] >> 14) & 0xff))
+
+                        elif 18 == page:
+                            s += "    Ionospheric and UTC data"
+                        elif 25 == page:
+                            s += "    A/S flags"
+                        else:
+                            s += "    Reserved"
+
                     elif 5 == subframe:
-                        s += ("\n   dataid %u svid %u\n" %
-                              (words[2] >> 28,
-                               (words[2] >> 22) & 0x3f))
+                        svid = (words[2] >> 22) & 0x3f
+                        page = index_s(svid, self.sbfr5_svid_page)
+                        s += ("\n   dataid %u svid %u (page %s)\n" %
+                              (words[2] >> 28, svid, page))
+
+                        if 1 <= page and 24 >= page:
+                            s += self.almanac(words)
+                        elif 25 == page:
+                            s += "    A/S flags"
+                        else:
+                            s += "    Reserved"
 
         return s