begin cleanup on gps code

src/GPS.cpp

@@ -0,0 +1,42 @@
+
+#include "GPS.h"
+
+HardwareSerial _serial_gps(GPS_SERIAL_NUM);
+
+GPS gps;
+
+GPS::GPS() : PeriodicTask(30 * 1000)
+{
+}
+
+void GPS::setup()
+{
+#ifdef GPS_RX_PIN
+    _serial_gps.begin(GPS_BAUDRATE, SERIAL_8N1, GPS_RX_PIN, GPS_TX_PIN);
+#endif
+}
+
+void GPS::loop()
+{
+    PeriodicTask::loop();
+
+#ifdef GPX_RX_PIN
+    while (_serial_gps.available())
+    {
+        _gps.encode(_serial_gps.read());
+    }
+#endif
+}
+
+void GPS::doTask()
+{
+}
+
+String GPS::getTime()
+{
+    static char t[12]; // used to sprintf for Serial output
+
+    snprintf(t, sizeof(t), "%02d:%02d:%02d", time.hour(), time.minute(), time.second());
+    return t;
+}
+

src/GPS.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <TinyGPS++.h>
+#include "PeriodicTask.h"
+#include "Observer.h"
+
+/**
+ * A gps class that only reads from the GPS periodically (and FIXME - eventually keeps the gps powered down except when reading)
+ * 
+ * When new data is available it will notify observers.
+ */
+class GPS : public PeriodicTask, public Observable, public TinyGPSPlus
+{
+public:
+    GPS();
+
+    String getTime();
+
+    void setup();
+
+    virtual void loop();
+
+    virtual void doTask();
+};
+
+extern GPS gps;

src/Observer.cpp

@@ -0,0 +1,13 @@
+#include "Observer.h"
+
+Observer::~Observer()
+{
+    if (observed)
+        observed->removeObserver(this);
+    observed = NULL;
+}
+
+void Observer::observe(Observable *o)
+{
+    o->addObserver(this);
+}

src/Observer.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <Arduino.h>
+
+#include <list>
+
+class Observable;
+
+class Observer
+{
+    Observable *observed;
+
+public:
+    Observer() : observed(NULL) {}
+
+    virtual ~Observer();
+
+    void observe(Observable *o);
+
+    virtual void onNotify(Observable *o) = 0;
+};
+
+class Observable
+{
+    std::list<Observer *> observers;
+
+public:
+    void notifyObservers()
+    {
+        for (std::list<Observer *>::const_iterator iterator = observers.begin(); iterator != observers.end(); ++iterator)
+        {
+            (*iterator)->onNotify(this);
+        }
+    }
+
+    void addObserver(Observer *o)
+    {
+        observers.push_back(o);
+    }
+
+    void removeObserver(Observer *o)
+    {
+        observers.remove(o);
+    }
+};
+

src/PeriodicTask.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <Arduino.h>
+#include "configuration.h"
+
+class PeriodicTask
+{
+    /// we use prevMsec rather than nextMsec because it is easier to handle the uint32 rollover in that case, also changes in periodMsec take effect immediately
+    uint32_t prevMsec;
+
+public:
+    uint32_t periodMsec;
+
+    virtual ~PeriodicTask() {}
+
+    PeriodicTask(uint32_t period) : periodMsec(period)
+    {
+        prevMsec = millis();
+    }
+
+    /// call this from loop
+    virtual void loop()
+    {
+        uint32_t now = millis();
+        if (now > (prevMsec + periodMsec))
+        {
+            // FIXME, this lets period slightly drift based on scheduling - not sure if that is always good
+            prevMsec = now;
+
+            DEBUG_MSG("Calling periodic task\n");
+            doTask();
+        }
+    }
+
+    virtual void doTask() = 0;
+};

src/gps.ino

@@ -1,70 +0,0 @@
-/*
-
-  GPS module
-
-  Copyright (C) 2018 by Xose Pérez <xose dot perez at gmail dot com>
-
-  This program is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  This program is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-*/
-
-#include <TinyGPS++.h>
-
-uint32_t LatitudeBinary;
-uint32_t LongitudeBinary;
-uint16_t altitudeGps;
-uint8_t hdopGps;
-uint8_t sats;
-char t[32]; // used to sprintf for Serial output
-
-TinyGPSPlus _gps;
-HardwareSerial _serial_gps(GPS_SERIAL_NUM);
-
-void gps_time(char * buffer, uint8_t size) {
-    snprintf(buffer, size, "%02d:%02d:%02d", _gps.time.hour(), _gps.time.minute(), _gps.time.second());
-}
-
-float gps_latitude() {
-    return _gps.location.lat();
-}
-
-float gps_longitude() {
-    return _gps.location.lng();
-}
-
-float gps_altitude() {
-    return _gps.altitude.meters();
-}
-
-float gps_hdop() {
-    return _gps.hdop.hdop();
-}
-
-uint8_t gps_sats() {
-    return _gps.satellites.value();
-}
-
-void gps_setup() {
-    #ifdef GPS_RX_PIN
-    _serial_gps.begin(GPS_BAUDRATE, SERIAL_8N1, GPS_RX_PIN, GPS_TX_PIN);
-    #endif
-}
-
-static void gps_loop() {
-    #ifdef GPX_RX_PIN
-    while (_serial_gps.available()) {
-        _gps.encode(_serial_gps.read());
-    }
-    #endif
-}

src/main.ino

@@ -29,6 +29,7 @@
 #include "BluetoothUtil.h"
 #include "MeshBluetoothService.h"
 #include "MeshService.h"
+#include "GPS.h"
 
 #ifdef T_BEAM_V10
 #include "axp20x.h"
@@ -348,7 +349,7 @@ void setup()
     screen_setup();
 
   // Init GPS
-  gps_setup();
+  gps.setup();
 
   // Show logo on first boot after removing battery
   //if (bootCount == 0) {
@@ -371,7 +372,7 @@ void setup()
 
 void loop()
 {
-  gps_loop();
+  gps.loop();
   screen_loop();
   service.loop();
   loopBLE();

src/screen.ino

@@ -25,6 +25,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "OLEDDisplay.h"
 #include "images.h"
 #include "fonts.h"
+#include "GPS.h"
 
 #define SCREEN_HEADER_HEIGHT    14
 
@@ -34,21 +35,19 @@ uint8_t _screen_line = SCREEN_HEADER_HEIGHT - 1;
 void _screen_header() {
     if(!display) return;
 
-    char buffer[20];
-
     // Message count
     //snprintf(buffer, sizeof(buffer), "#%03d", ttn_get_count() % 1000);
     //display->setTextAlignment(TEXT_ALIGN_LEFT);
     //display->drawString(0, 2, buffer);
 
     // Datetime
-    gps_time(buffer, sizeof(buffer));
     display->setTextAlignment(TEXT_ALIGN_CENTER);
-    display->drawString(display->getWidth()/2, 2, buffer);
+    display->drawString(display->getWidth()/2, 2, gps.getTime());
 
     // Satellite count
     display->setTextAlignment(TEXT_ALIGN_RIGHT);
-    display->drawString(display->getWidth() - SATELLITE_IMAGE_WIDTH - 4, 2, itoa(gps_sats(), buffer, 10));
+    char buffer[10];
+    display->drawString(display->getWidth() - SATELLITE_IMAGE_WIDTH - 4, 2, itoa(gps.satellites.value(), buffer, 10));
     display->drawXbm(display->getWidth() - SATELLITE_IMAGE_WIDTH, 0, SATELLITE_IMAGE_WIDTH, SATELLITE_IMAGE_HEIGHT, SATELLITE_IMAGE);
 }