add air530 gps sleep support

src/gps/Air530GPS.cpp

@@ -0,0 +1,87 @@
+#include "Air530GPS.h"
+#include <assert.h>
+
+/*
+Helpful translations from the Air530 GPS datasheet
+
+Sat acquision mode
+捕获电流值@3.3v 42.6 mA
+
+sat tracking mode
+跟踪电流值@3.3v 36.7 mA
+
+Low power mode
+低功耗模式@3.3V 0.85 mA
+(发送指令:$PGKC051,0)
+
+Super low power mode
+超低功耗模式@3.3V 31 uA
+(发送指令:$PGKC105,4)
+
+To exit sleep use WAKE pin
+
+Commands to enter sleep
+6、Command: 105
+进入周期性低功耗模式
+Arguments:
+
+Arg1: “0”,正常运行模式 (normal mode)
+“1”,周期超低功耗跟踪模式,需要拉高 WAKE 来唤醒 (periodic low power tracking mode - keeps sat positions, use wake to wake up)
+“2”,周期低功耗模式 (periodic low power mode)
+“4”,直接进入超低功耗跟踪模式,需要拉高 WAKE 来唤醒 (super low power consumption mode immediately, need WAKE to resume)
+“8”,自动低功耗模式,可以通过串口唤醒 (automatic low power mode, wake by sending characters to serial port)
+“9”, 自动超低功耗跟踪模式,需要拉高 WAKE 来唤醒 (automatic low power tracking when possible, need wake pin to resume)
+
+(Arg 2 & 3 only valid if Arg1 is "1" or "2")
+Arg2:运行时间(毫秒),在 Arg1 为 1、2 的周期模式下,此参数起作用
+ON time in msecs
+
+Arg3:睡眠时间(毫秒),在 Arg1 为 1、2 的周期模式下,此参数起作用
+Sleep time in msecs
+
+Example:
+$PGKC105,8*3F<CR><LF>
+This will set automatic low power mode with waking when we send chars to the serial port.  Possibly do this as soon as we get a
+new location.  When we wake again in a minute we send a character to wake up.
+
+*/
+
+
+void Air530GPS::sendCommand(const char *cmd) {
+    uint8_t sum = 0;
+
+    // Skip the $
+    assert(cmd[0] == '$');
+    const char *p = cmd + 1;
+    while(*p)
+        sum ^= *p++;
+
+    assert(_serial_gps);
+   
+    _serial_gps->write(cmd);
+    _serial_gps->printf("*%02x\r\n", sum);
+
+    // DEBUG_MSG("xsum %02x\n", sum);
+}
+
+void Air530GPS::sleep() {
+#ifdef PIN_GPS_WAKE
+    digitalWrite(PIN_GPS_WAKE, 0);
+    pinMode(PIN_GPS_WAKE, OUTPUT);
+    sendCommand("$PGKC105,4");
+#endif
+}
+
+/// wake the GPS into normal operation mode
+void Air530GPS::wake()
+{
+#if 0
+#ifdef PIN_GPS_WAKE
+    digitalWrite(PIN_GPS_WAKE, 1);
+    pinMode(PIN_GPS_WAKE, OUTPUT);
+#endif
+#else
+    // For power testing
+    sleep();
+#endif
+}

src/gps/Air530GPS.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "NMEAGPS.h"
+
+/**
+ * A gps class thatreads from a NMEA GPS stream (and FIXME - eventually keeps the gps powered down except when reading)
+ *
+ * When new data is available it will notify observers.
+ */
+class Air530GPS : public NMEAGPS
+{
+  protected:
+    /// If possible force the GPS into sleep/low power mode
+    virtual void sleep();
+
+    /// wake the GPS into normal operation mode
+    virtual void wake();
+
+  private:
+    /// Send a NMEA cmd with checksum
+    void sendCommand(const char *str);
+};

src/gps/GPS.cpp

@@ -85,3 +85,20 @@ uint32_t getValidTime()
 {
     return timeSetFromGPS ? getTime() : 0;
 }
+
+/**
+ * Switch the GPS into a mode where we are actively looking for a lock, or alternatively switch GPS into a low power mode
+ *
+ * calls sleep/wake
+ */
+void GPS::setWantLocation(bool on)
+{
+    if (wantNewLocation != on) {
+        wantNewLocation = on;
+        DEBUG_MSG("WANT GPS=%d\n", on);
+        if (on)
+            wake();
+        else
+            sleep();
+        }
+}

src/gps/GPS.h

@@ -30,6 +30,8 @@ class GPS
   protected:
     bool hasValidLocation = false; // default to false, until we complete our first read
 
+    bool wantNewLocation = false; // true if we want a location right now
+
   public:
     /** If !NULL we will use this serial port to construct our GPS */
     static HardwareSerial *_serial_gps;
@@ -62,10 +64,24 @@ class GPS
     /// Returns ture if we have acquired GPS lock.
     bool hasLock() const { return hasValidLocation; }
 
+    /**
+     * Switch the GPS into a mode where we are actively looking for a lock, or alternatively switch GPS into a low power mode
+     * 
+     * calls sleep/wake
+     */
+    void setWantLocation(bool on);
+
     /**
      * Restart our lock attempt - try to get and broadcast a GPS reading ASAP
      * called after the CPU wakes from light-sleep state */
     virtual void startLock() {}
+
+protected:
+  /// If possible force the GPS into sleep/low power mode
+  virtual void sleep() {}
+
+  /// wake the GPS into normal operation mode
+  virtual void wake() {}
 };
 
 extern GPS *gps;

src/gps/NMEAGPS.cpp

@@ -1,50 +1,6 @@
 #include "NMEAGPS.h"
 #include "configuration.h"
 
-/*
-Helpful translations from the Air530 GPS datasheet
-
-Sat acquision mode
-捕获电流值@3.3v 42.6 mA
-
-sat tracking mode
-跟踪电流值@3.3v 36.7 mA
-
-Low power mode
-低功耗模式@3.3V 0.85 mA
-(发送指令:$PGKC051,0)
-
-Super low power mode
-超低功耗模式@3.3V 31 uA
-(发送指令:$PGKC105,4)
-
-To exit sleep use WAKE pin
-
-Commands to enter sleep
-6、Command: 105
-进入周期性低功耗模式
-Arguments:
-
-Arg1: “0”,正常运行模式 (normal mode)
-“1”,周期超低功耗跟踪模式,需要拉高 WAKE 来唤醒 (periodic low power tracking mode - keeps sat positions, use wake to wake up)
-“2”,周期低功耗模式 (periodic low power mode)
-“4”,直接进入超低功耗跟踪模式,需要拉高 WAKE 来唤醒 (super low power consumption mode immediately, need WAKE to resume)
-“8”,自动低功耗模式,可以通过串口唤醒 (automatic low power mode, wake by sending characters to serial port)
-“9”, 自动超低功耗跟踪模式,需要拉高 WAKE 来唤醒 (automatic low power tracking when possible, need wake pin to resume)
-
-(Arg 2 & 3 only valid if Arg1 is "1" or "2")
-Arg2:运行时间(毫秒),在 Arg1 为 1、2 的周期模式下,此参数起作用
-ON time in msecs
-
-Arg3:睡眠时间(毫秒),在 Arg1 为 1、2 的周期模式下,此参数起作用
-Sleep time in msecs
-
-Example:
-$PGKC105,8*3F<CR><LF>
-This will set automatic low power mode with waking when we send chars to the serial port.  Possibly do this as soon as we get a new 
-location.  When we wake again in a minute we send a character to wake up.
-
-*/
 
 static int32_t toDegInt(RawDegrees d)
 {
@@ -68,6 +24,7 @@ bool NMEAGPS::setup()
 
 void NMEAGPS::loop()
 {
+    // First consume any chars that have piled up at the receiver
     while (_serial_gps->available() > 0) {
         int c = _serial_gps->read();
         // DEBUG_MSG("%c", c);
@@ -78,11 +35,18 @@ void NMEAGPS::loop()
             isConnected = true;
     }
 
+    // If we are overdue for an update, turn on the GPS and at least publish the current status
     uint32_t now = millis();
-    if ((now - lastUpdateMsec) > 20 * 1000) { // Ugly hack for now - limit update checks to once every 20 secs (but still consume
+    bool mustPublishUpdate = false;
-                                              // serial chars at whatever rate)
+    if ((now - lastUpdateMsec) > 30 * 1000 && !wantNewLocation) {
-        lastUpdateMsec = now;
+        // Ugly hack for now - limit update checks to once every 30 secs
+        setWantLocation(true);
+        mustPublishUpdate =
+            true; // Even if we don't have an update this time, we at least want to occasionally publish the current state
+    }
 
+    // Only bother looking at GPS state if we are interested in what it has to say
+    if (wantNewLocation) {
         auto ti = reader.time;
         auto d = reader.date;
         if (ti.isUpdated() && ti.isValid() && d.isValid()) {
@@ -105,6 +69,8 @@ void NMEAGPS::loop()
         hasValidLocation = ((fixtype >= 1) && (fixtype <= 5));
 
         if (reader.location.isUpdated()) {
+            lastUpdateMsec = now;
+
             if (reader.altitude.isValid())
                 altitude = reader.altitude.meters();
 
@@ -112,6 +78,9 @@ void NMEAGPS::loop()
                 auto loc = reader.location.value();
                 latitude = toDegInt(loc.lat);
                 longitude = toDegInt(loc.lng);
+
+                // Once we get a location we no longer desperately want an update
+                setWantLocation(false);
             }
             // Diminution of precision (an accuracy metric) is reported in 10^2 units, so we need to scale down when we use it
             if (reader.hdop.isValid()) {
@@ -128,11 +97,14 @@ void NMEAGPS::loop()
             // expect gps pos lat=37.520825, lon=-122.309162, alt=158
             DEBUG_MSG("new NMEA GPS pos lat=%f, lon=%f, alt=%d, hdop=%g, heading=%f\n", latitude * 1e-7, longitude * 1e-7,
                       altitude, dop * 1e-2, heading * 1e-5);
+            mustPublishUpdate = true;
         }
 
-        // Notify any status instances that are observing us
+        if (mustPublishUpdate) {
-        const meshtastic::GPSStatus status =
+            // Notify any status instances that are observing us
-            meshtastic::GPSStatus(hasLock(), isConnected, latitude, longitude, altitude, dop, heading, numSatellites);
+            const meshtastic::GPSStatus status =
-        newStatus.notifyObservers(&status);
+                meshtastic::GPSStatus(hasLock(), isConnected, latitude, longitude, altitude, dop, heading, numSatellites);
+            newStatus.notifyObservers(&status);
+        }
     }
 }

src/gps/UBloxGPS.cpp

@@ -183,11 +183,11 @@ void UBloxGPS::doTask()
         if ((fixtype >= 3 && fixtype <= 4) && ublox.getP(maxWait)) // rd fixes only
         {
             if (hasValidLocation) {
-                wantNewLocation = false;
+                setWantLocation(false);
                 // ublox.powerOff();
             }
         } else // we didn't get a location update, go back to sleep and hope the characters show up
-            wantNewLocation = true;
+            setWantLocation(true);
 
         // Notify any status instances that are observing us
         const meshtastic::GPSStatus status =

src/gps/UBloxGPS.h

@@ -14,8 +14,6 @@ class UBloxGPS : public GPS, public concurrency::PeriodicTask
 {
     SFE_UBLOX_GPS ublox;
 
-    bool wantNewLocation = true;
-
     CallbackObserver<UBloxGPS, void *> notifySleepObserver = CallbackObserver<UBloxGPS, void *>(this, &UBloxGPS::prepareSleep);
 
   public:

src/graphics/EInkDisplay.cpp

@@ -62,7 +62,7 @@ void EInkDisplay::display(void)
     uint32_t now = millis();
     uint32_t sinceLast = now - lastDrawMsec;
 
-    if (framePtr && (sinceLast > 30 * 1000 || lastDrawMsec == 0)) {
+    if (framePtr && (sinceLast > 60 * 1000 || lastDrawMsec == 0)) {
         lastDrawMsec = now;
 
         // FIXME - only draw bits have changed (use backbuf similar to the other displays)

src/main.cpp

@@ -23,7 +23,7 @@
 
 #include "MeshRadio.h"
 #include "MeshService.h"
-#include "NMEAGPS.h"
+#include "Air530GPS.h"
 #include "NodeDB.h"
 #include "PowerFSM.h"
 #include "UBloxGPS.h"
@@ -259,10 +259,14 @@ void setup()
         if (GPS::_serial_gps) {
             // Some boards might have only the TX line from the GPS connected, in that case, we can't configure it at all.  Just
             // assume NMEA at 9600 baud.
+            // dumb NMEA access only work for serial GPSes)
             DEBUG_MSG("Hoping that NMEA might work\n");
 
-            // dumb NMEA access only work for serial GPSes)
+#ifdef HAS_AIR530_GPS
+            gps = new Air530GPS();
+#else
             gps = new NMEAGPS();
+#endif
             gps->setup();
         }
     }

variants/eink/variant.h

@@ -208,6 +208,8 @@ External serial flash WP25R1635FZUIL0
 #define PIN_GPS_TX (32 + 9)   // This is for bits going TOWARDS the CPU
 #define PIN_GPS_RX (32 + 8)   // This is for bits going TOWARDS the GPS
 
+#define HAS_AIR530_GPS
+
 #define PIN_SERIAL1_RX PIN_GPS_TX
 #define PIN_SERIAL1_TX PIN_GPS_RX