abstract out the UBlox GPS driver

src/gps/UBloxGPS.cpp

@@ -0,0 +1,153 @@
+#include "UBloxGPS.h"
+#include "sleep.h"
+#include <assert.h>
+
+UBloxGPS::UBloxGPS() : PeriodicTask()
+{
+    notifySleepObserver.observe(&notifySleep);
+}
+
+bool UBloxGPS::setup()
+{
+    PeriodicTask::setup();
+
+#ifdef GPS_RX_PIN
+    _serial_gps.begin(GPS_BAUDRATE, SERIAL_8N1, GPS_RX_PIN, GPS_TX_PIN);
+#else
+    _serial_gps.begin(GPS_BAUDRATE);
+#endif
+    // _serial_gps.setRxBufferSize(1024); // the default is 256
+    // ublox.enableDebugging(Serial);
+
+    // note: the lib's implementation has the wrong docs for what the return val is
+    // it is not a bool, it returns zero for success
+    isConnected = ublox.begin(_serial_gps);
+
+    // try a second time, the ublox lib serial parsing is buggy?
+    if (!isConnected)
+        isConnected = ublox.begin(_serial_gps);
+
+    if (isConnected) {
+        DEBUG_MSG("Connected to UBLOX GPS successfully\n");
+
+        bool factoryReset = false;
+        bool ok;
+        if (factoryReset) {
+            // It is useful to force back into factory defaults (9600baud, NEMA to test the behavior of boards that don't have
+            // GPS_TX connected)
+            ublox.factoryReset();
+            delay(2000);
+            isConnected = ublox.begin(_serial_gps);
+            DEBUG_MSG("Factory reset success=%d\n", isConnected);
+            if (isConnected) {
+                ublox.assumeAutoPVT(true, true); // Just parse NEMA for now
+            }
+        } else {
+            ok = ublox.setUART1Output(COM_TYPE_UBX, 500); // Use native API
+            assert(ok);
+            ok = ublox.setNavigationFrequency(1, 500); // Produce 4x/sec to keep the amount of time we stall in getPVT low
+            assert(ok);
+            // ok = ublox.setAutoPVT(false); // Not implemented on NEO-6M
+            // assert(ok);
+            // ok = ublox.setDynamicModel(DYN_MODEL_BIKE); // probably PEDESTRIAN but just in case assume bike speeds
+            // assert(ok);
+            ok = ublox.powerSaveMode(); // use power save mode
+            assert(ok);
+        }
+        ok = ublox.saveConfiguration(3000);
+        assert(ok);
+
+        return true;
+    } else {
+        // Some boards might have only the TX line from the GPS connected, in that case, we can't configure it at all.  Just
+        // assume NEMA at 9600 baud.
+        DEBUG_MSG("ERROR: No bidirectional GPS found, hoping that it still might work\n");
+
+        return false;
+    }
+}
+
+/// Prepare the GPS for the cpu entering deep or light sleep, expect to be gone for at least 100s of msecs
+int UBloxGPS::prepareSleep(void *unused)
+{
+    if (isConnected)
+        ublox.powerOff();
+
+    return 0;
+}
+
+void UBloxGPS::doTask()
+{
+    uint8_t fixtype = 3; // If we are only using the RX pin, assume we have a 3d fix
+
+    if (isConnected) {
+        // Consume all characters that have arrived
+
+        // getPVT automatically calls checkUblox
+        ublox.checkUblox(); // See if new data is available. Process bytes as they come in.
+
+        // If we don't have a fix (a quick check), don't try waiting for a solution)
+        // Hmmm my fix type reading returns zeros for fix, which doesn't seem correct, because it is still sptting out positions
+        // turn off for now
+        // fixtype = ublox.getFixType();
+        DEBUG_MSG("fix type %d\n", fixtype);
+    }
+
+    // DEBUG_MSG("sec %d\n", ublox.getSecond());
+    // DEBUG_MSG("lat %d\n", ublox.getLatitude());
+
+    // any fix that has time
+    if (ublox.getT()) {
+        struct timeval tv;
+
+        /* Convert to unix time
+The Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of seconds that have elapsed since January 1, 1970
+(midnight UTC/GMT), not counting leap seconds (in ISO 8601: 1970-01-01T00:00:00Z).
+*/
+        struct tm t;
+        t.tm_sec = ublox.getSecond();
+        t.tm_min = ublox.getMinute();
+        t.tm_hour = ublox.getHour();
+        t.tm_mday = ublox.getDay();
+        t.tm_mon = ublox.getMonth() - 1;
+        t.tm_year = ublox.getYear() - 1900;
+        t.tm_isdst = false;
+        time_t res = mktime(&t);
+        tv.tv_sec = res;
+        tv.tv_usec = 0; // time.centisecond() * (10 / 1000);
+
+        DEBUG_MSG("Got time from GPS month=%d, year=%d, unixtime=%ld\n", t.tm_mon, t.tm_year, tv.tv_sec);
+        if (t.tm_year < 0 || t.tm_year >= 300)
+            DEBUG_MSG("Ignoring invalid GPS time\n");
+        else
+            perhapsSetRTC(&tv);
+    }
+
+    if ((fixtype >= 3 && fixtype <= 4) && ublox.getP()) // rd fixes only
+    {
+        // we only notify if position has changed
+        latitude = ublox.getLatitude();
+        longitude = ublox.getLongitude();
+        altitude = ublox.getAltitude() / 1000; // in mm convert to meters
+        DEBUG_MSG("new gps pos lat=%f, lon=%f, alt=%d\n", latitude * 1e-7, longitude * 1e-7, altitude);
+
+        hasValidLocation = (latitude != 0) || (longitude != 0); // bogus lat lon is reported as 0,0
+        if (hasValidLocation) {
+            wantNewLocation = false;
+            notifyObservers(NULL);
+            // ublox.powerOff();
+        }
+    } else // we didn't get a location update, go back to sleep and hope the characters show up
+        wantNewLocation = true;
+
+    // Once we have sent a location once we only poll the GPS rarely, otherwise check back every 1s until we have something over
+    // the serial
+    setPeriod(hasValidLocation && !wantNewLocation ? 30 * 1000 : 10 * 1000);
+}
+
+void UBloxGPS::startLock()
+{
+    DEBUG_MSG("Looking for GPS lock\n");
+    wantNewLocation = true;
+    setPeriod(1);
+}