Add workaround for Unicore GLL firmware issue

RELEASE_NOTES.md

@@ -1,5 +1,9 @@
 # pynmeagps Release Notes
 
+### RELEASE 1.1.2
+
+1. Add workaround for Unicore UM9* firmware error, which creates malformed NMEA GLL sentences (-ve latitude).
+
 ### RELEASE 1.1.1
 
 1. Add helper methods `utc2wnotow` and `wnotow2utc` to convert between UTC datetime and GPS week number, time of week (in milliseconds) and leapsecond offset.

src/pynmeagps/_version.py

@@ -8,4 +8,4 @@
 :license: BSD 3-Clause
 """
 
-__version__ = "1.1.1"
+__version__ = "1.1.2"

src/pynmeagps/nmeahelpers.py

@@ -276,7 +276,7 @@ def dmm2ddd(pos: str) -> float | str:
         dp = pos.find(".")
         if dp < 4:
             raise ValueError()
-        posdeg = float(pos[0 : dp - 2])
+        posdeg = abs(float(pos[0 : dp - 2]))
         posmin = float(pos[dp - 2 :])
         return round((posdeg + posmin / 60), 10)
     except (TypeError, ValueError):

tests/pygpsdata-um981.log

@@ -0,0 +1,6 @@
+$GNGGA,130058.00,5327.03598945,N,00214.41467156,W,1,08,7.5,36.3017,M,51.6775,M,,*5B
+$GNGLL,5327.03598945,N,-0214.41467156,W,130058.00,A,A*7E
+$GNRMC,130058.00,A,5327.03598945,N,00214.41467156,W,0.097,125.7,240226,0.2,W,A,C*4F
+$GNGGA,130059.00,5327.03598242,N,00214.41468053,W,1,08,7.5,36.3232,M,51.6775,M,,*58
+$GNGLL,5327.03598242,N,-0214.41468053,W,130059.00,A,A*78
+

tests/test_stream.py

@@ -701,6 +701,24 @@ def testNMEAUnicore(self):  # test Unicore extended NMEA GET messages
                     i += 1
         self.assertEqual(i, len(EXPECTED_RESULTS))
 
+    def testNMEAUM981(self):  # test Unicore GLL firmware error workaround
+        EXPECTED_RESULTS = (
+            "<NMEA(GNGGA, time=13:00:58, lat=53.4505998242, NS=N, lon=-2.240244526, EW=W, quality=1, numSV=8, HDOP=7.5, alt=36.3017, altUnit=M, sep=51.6775, sepUnit=M, diffAge=, diffStation=)>",
+            "<NMEA(GNGLL, lat=53.4505998242, NS=N, lon=-2.240244526, EW=W, time=13:00:58, status=A, posMode=A)>",
+            "<NMEA(GNRMC, time=13:00:58, status=A, lat=53.4505998242, NS=N, lon=-2.240244526, EW=W, spd=0.097, cog=125.7, date=2026-02-24, mv=0.2, mvEW=W, posMode=A, navStatus=C)>",
+            "<NMEA(GNGGA, time=13:00:59, lat=53.450599707, NS=N, lon=-2.2402446755, EW=W, quality=1, numSV=8, HDOP=7.5, alt=36.3232, altUnit=M, sep=51.6775, sepUnit=M, diffAge=, diffStation=)>",
+            "<NMEA(GNGLL, lat=53.450599707, NS=N, lon=-2.2402446755, EW=W, time=13:00:59, status=A, posMode=A)>",
+        )
+        i = 0
+        with open(os.path.join(DIRNAME, "pygpsdata-um981.log"), "rb") as stream:
+            nmr = NMEAReader(stream, nmeaonly=False, quitonerror=2)
+            for raw, parsed in nmr:
+                if raw is not None:
+                    # print(f'"{parsed}",')
+                    self.assertEqual(str(parsed), EXPECTED_RESULTS[i])
+                    i += 1
+        self.assertEqual(i, len(EXPECTED_RESULTS))
+
     def testBADHDR_FAIL(self):  # invalid header in data with quitonerror = 2
         EXPECTED_ERROR = "Unknown protocol header b'$&'."
         with self.assertRaises(NMEAParseError) as context: