Merge pull request #237 from Professr/issue#182

Switch main display to event-driven model, abstract the three main status info categories, work on power.h

src/GPSStatus.h

@@ -0,0 +1,108 @@
+#pragma once
+#include <Arduino.h>
+#include "Status.h"
+#include "configuration.h"
+
+namespace meshtastic {
+
+    /// Describes the state of the GPS system.
+    class GPSStatus : public Status
+    {
+
+       private:
+        CallbackObserver<GPSStatus, const GPSStatus *> statusObserver = CallbackObserver<GPSStatus, const GPSStatus *>(this, &GPSStatus::updateStatus);
+
+        bool hasLock = false; // default to false, until we complete our first read
+        bool isConnected = false; // Do we have a GPS we are talking to
+        int32_t latitude = 0, longitude = 0; // as an int mult by 1e-7 to get value as double
+        int32_t altitude = 0;
+        uint32_t dop = 0; // Diminution of position; PDOP where possible (UBlox), HDOP otherwise (TinyGPS) in 10^2 units (needs scaling before use)
+
+       public:
+
+        GPSStatus() {
+            statusType = STATUS_TYPE_GPS;
+        }
+        GPSStatus( bool hasLock, bool isConnected, int32_t latitude, int32_t longitude, int32_t altitude, uint32_t dop ) : Status()
+        {
+            this->hasLock = hasLock;
+            this->isConnected = isConnected;
+            this->latitude = latitude;
+            this->longitude = longitude;
+            this->altitude = altitude;
+            this->dop = dop;
+        }
+        GPSStatus(const GPSStatus &);
+        GPSStatus &operator=(const GPSStatus &);
+
+        void observe(Observable<const GPSStatus *> *source)
+        {
+            statusObserver.observe(source);
+        }
+
+        bool getHasLock() const
+        { 
+            return hasLock; 
+        }
+
+        bool getIsConnected() const
+        { 
+            return isConnected; 
+        }
+
+        int32_t getLatitude() const
+        { 
+            return latitude; 
+        }
+
+        int32_t getLongitude() const
+        { 
+            return longitude;
+        }
+
+        int32_t getAltitude() const
+        { 
+            return altitude; 
+        }
+
+        uint32_t getDOP() const
+        { 
+            return dop; 
+        }
+
+        bool matches(const GPSStatus *newStatus) const
+        {
+            return (
+                newStatus->hasLock != hasLock ||
+                newStatus->isConnected != isConnected ||
+                newStatus->latitude != latitude ||
+                newStatus->longitude != longitude ||
+                newStatus->altitude != altitude ||
+                newStatus->dop != dop
+            );
+        }
+        int updateStatus(const GPSStatus *newStatus) {
+            // Only update the status if values have actually changed
+            bool isDirty;
+            {
+                isDirty = matches(newStatus);
+                initialized = true; 
+                hasLock = newStatus->hasLock;
+                isConnected = newStatus->isConnected;
+                latitude = newStatus->latitude;
+                longitude = newStatus->longitude;
+                altitude = newStatus->altitude;
+                dop = newStatus->dop;
+            }
+            if(isDirty) {
+                DEBUG_MSG("New GPS pos lat=%f, lon=%f, alt=%d, pdop=%f\n", latitude * 1e-7, longitude * 1e-7, altitude, dop * 1e-2);            
+                onNewStatus.notifyObservers(this);
+            }
+            return 0;
+        }
+
+    };
+
+}
+
+extern meshtastic::GPSStatus *gpsStatus;

src/NodeStatus.h

@@ -0,0 +1,73 @@
+#pragma once
+#include <Arduino.h>
+#include "Status.h"
+#include "configuration.h"
+
+namespace meshtastic {
+
+    /// Describes the state of the NodeDB system.
+    class NodeStatus : public Status
+    {
+
+       private:
+        CallbackObserver<NodeStatus, const NodeStatus *> statusObserver = CallbackObserver<NodeStatus, const NodeStatus *>(this, &NodeStatus::updateStatus);
+
+        uint8_t numOnline = 0;
+        uint8_t numTotal = 0;
+
+       public:
+
+        NodeStatus() {
+            statusType = STATUS_TYPE_NODE;
+        }
+        NodeStatus( uint8_t numOnline, uint8_t numTotal ) : Status()
+        {
+            this->numOnline = numOnline;
+            this->numTotal = numTotal;
+        }
+        NodeStatus(const NodeStatus &);
+        NodeStatus &operator=(const NodeStatus &);
+
+        void observe(Observable<const NodeStatus *> *source)
+        {
+            statusObserver.observe(source);
+        }
+
+        uint8_t getNumOnline() const
+        { 
+            return numOnline; 
+        }
+
+        uint8_t getNumTotal() const
+        { 
+            return numTotal; 
+        }
+
+        bool matches(const NodeStatus *newStatus) const
+        {
+            return (
+                newStatus->getNumOnline() != numOnline ||
+                newStatus->getNumTotal() != numTotal
+            );
+        }
+        int updateStatus(const NodeStatus *newStatus) {
+            // Only update the status if values have actually changed
+            bool isDirty;
+            {
+                isDirty = matches(newStatus);
+                initialized = true; 
+                numOnline = newStatus->getNumOnline();
+                numTotal = newStatus->getNumTotal();
+            }
+            if(isDirty) {
+                DEBUG_MSG("Node status update: %d online, %d total\n", numOnline, numTotal);            
+                onNewStatus.notifyObservers(this);
+            }
+            return 0;
+        }
+
+    };
+
+}
+
+extern meshtastic::NodeStatus *nodeStatus;

src/Power.cpp

@@ -0,0 +1,180 @@
+#include "power.h"
+#include "PowerFSM.h"
+#include "main.h"
+#include "utils.h"
+#include "sleep.h"
+
+
+#ifdef TBEAM_V10
+
+// FIXME. nasty hack cleanup how we load axp192
+#undef AXP192_SLAVE_ADDRESS
+#include "axp20x.h"
+AXP20X_Class axp;
+bool pmu_irq = false;
+
+Power *power;
+
+bool Power::setup() 
+{
+
+    axp192Init();
+    PeriodicTask::setup(); // We don't start our periodic task unless we actually found the device
+    setPeriod(1);
+
+    return axp192_found;
+}
+
+/// Reads power status to powerStatus singleton.
+//
+// TODO(girts): move this and other axp stuff to power.h/power.cpp.
+void Power::readPowerStatus()
+{
+    bool hasBattery = axp.isBatteryConnect();
+    int batteryVoltageMv = 0;
+    uint8_t batteryChargePercent = 0;
+    if (hasBattery) {
+        batteryVoltageMv = axp.getBattVoltage();
+        // If the AXP192 returns a valid battery percentage, use it
+        if (axp.getBattPercentage() >= 0) {
+            batteryChargePercent = axp.getBattPercentage();
+        } else {
+            // If the AXP192 returns a percentage less than 0, the feature is either not supported or there is an error
+            // In that case, we compute an estimate of the charge percent based on maximum and minimum voltages defined in power.h
+            batteryChargePercent = clamp((int)(((batteryVoltageMv - BAT_MILLIVOLTS_EMPTY) * 1e2) / (BAT_MILLIVOLTS_FULL - BAT_MILLIVOLTS_EMPTY)), 0, 100);
+        }
+    }
+
+    // Notify any status instances that are observing us
+    const meshtastic::PowerStatus powerStatus = meshtastic::PowerStatus(hasBattery, axp.isVBUSPlug(), axp.isChargeing(), batteryVoltageMv, batteryChargePercent);
+    newStatus.notifyObservers(&powerStatus);
+
+    // If we have a battery at all and it is less than 10% full, force deep sleep
+    if (powerStatus.getHasBattery() && !powerStatus.getHasUSB() &&
+        axp.getBattVoltage() < MIN_BAT_MILLIVOLTS)
+        powerFSM.trigger(EVENT_LOW_BATTERY);
+}
+
+void Power::doTask() 
+{
+    readPowerStatus();
+    
+    // Only read once every 20 seconds once the power status for the app has been initialized
+    if(statusHandler && statusHandler->isInitialized())
+        setPeriod(1000 * 20);
+}
+#endif // TBEAM_V10
+
+#ifdef AXP192_SLAVE_ADDRESS
+/**
+ * Init the power manager chip
+ *
+ * axp192 power
+    DCDC1 0.7-3.5V @ 1200mA max -> OLED // If you turn this off you'll lose comms to the axp192 because the OLED and the axp192
+ share the same i2c bus, instead use ssd1306 sleep mode DCDC2 -> unused DCDC3 0.7-3.5V @ 700mA max -> ESP32 (keep this on!) LDO1
+ 30mA -> charges GPS backup battery // charges the tiny J13 battery by the GPS to power the GPS ram (for a couple of days), can
+ not be turned off LDO2 200mA -> LORA LDO3 200mA -> GPS
+ */
+void Power::axp192Init()
+{
+    if (axp192_found) {
+        if (!axp.begin(Wire, AXP192_SLAVE_ADDRESS)) {
+            DEBUG_MSG("AXP192 Begin PASS\n");
+
+            // axp.setChgLEDMode(LED_BLINK_4HZ);
+            DEBUG_MSG("DCDC1: %s\n", axp.isDCDC1Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("DCDC2: %s\n", axp.isDCDC2Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("LDO2: %s\n", axp.isLDO2Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("LDO3: %s\n", axp.isLDO3Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("DCDC3: %s\n", axp.isDCDC3Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("Exten: %s\n", axp.isExtenEnable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("----------------------------------------\n");
+
+            axp.setPowerOutPut(AXP192_LDO2, AXP202_ON); // LORA radio
+            axp.setPowerOutPut(AXP192_LDO3, AXP202_ON); // GPS main power
+            axp.setPowerOutPut(AXP192_DCDC2, AXP202_ON);
+            axp.setPowerOutPut(AXP192_EXTEN, AXP202_ON);
+            axp.setPowerOutPut(AXP192_DCDC1, AXP202_ON);
+            axp.setDCDC1Voltage(3300); // for the OLED power
+
+            DEBUG_MSG("DCDC1: %s\n", axp.isDCDC1Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("DCDC2: %s\n", axp.isDCDC2Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("LDO2: %s\n", axp.isLDO2Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("LDO3: %s\n", axp.isLDO3Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("DCDC3: %s\n", axp.isDCDC3Enable() ? "ENABLE" : "DISABLE");
+            DEBUG_MSG("Exten: %s\n", axp.isExtenEnable() ? "ENABLE" : "DISABLE");
+
+            axp.setChargeControlCur(AXP1XX_CHARGE_CUR_1320MA); // actual limit (in HW) on the tbeam is 450mA
+#if 0
+
+      // Not connected
+      //val = 0xfc;
+      //axp._writeByte(AXP202_VHTF_CHGSET, 1, &val); // Set temperature protection
+
+      //not used
+      //val = 0x46;
+      //axp._writeByte(AXP202_OFF_CTL, 1, &val); // enable bat detection
+#endif
+            axp.debugCharging();
+
+#ifdef PMU_IRQ
+            pinMode(PMU_IRQ, INPUT);
+            attachInterrupt(
+                PMU_IRQ, [] { pmu_irq = true; }, FALLING);
+
+            axp.adc1Enable(AXP202_BATT_CUR_ADC1, 1);
+            axp.enableIRQ(AXP202_BATT_REMOVED_IRQ | AXP202_BATT_CONNECT_IRQ | AXP202_CHARGING_FINISHED_IRQ | AXP202_CHARGING_IRQ |
+                              AXP202_VBUS_REMOVED_IRQ | AXP202_VBUS_CONNECT_IRQ | AXP202_PEK_SHORTPRESS_IRQ,
+                          1);
+
+            axp.clearIRQ();
+#endif
+            readPowerStatus();
+        } else {
+            DEBUG_MSG("AXP192 Begin FAIL\n");
+        }
+    } else {
+        DEBUG_MSG("AXP192 not found\n");
+    }
+}
+#endif
+
+void Power::loop() 
+{
+
+#ifdef PMU_IRQ
+    if (pmu_irq) {
+        pmu_irq = false;
+        axp.readIRQ();
+
+        DEBUG_MSG("pmu irq!\n");
+
+        if (axp.isChargingIRQ()) {
+            DEBUG_MSG("Battery start charging\n");
+        }
+        if (axp.isChargingDoneIRQ()) {
+            DEBUG_MSG("Battery fully charged\n");
+        }
+        if (axp.isVbusRemoveIRQ()) {
+            DEBUG_MSG("USB unplugged\n");
+        }
+        if (axp.isVbusPlugInIRQ()) {
+            DEBUG_MSG("USB plugged In\n");
+        }
+        if (axp.isBattPlugInIRQ()) {
+            DEBUG_MSG("Battery inserted\n");
+        }
+        if (axp.isBattRemoveIRQ()) {
+            DEBUG_MSG("Battery removed\n");
+        }
+        if (axp.isPEKShortPressIRQ()) {
+            DEBUG_MSG("PEK short button press\n");
+        }
+
+        readPowerStatus();
+        axp.clearIRQ();
+    }
+
+#endif // T_BEAM_V10
+
+}

src/PowerStatus.h

@@ -0,0 +1,103 @@
+#pragma once
+#include <Arduino.h>
+#include "Status.h"
+#include "configuration.h"
+
+namespace meshtastic {
+
+    /// Describes the state of the GPS system.
+    class PowerStatus : public Status
+    {
+
+       private:
+        CallbackObserver<PowerStatus, const PowerStatus *> statusObserver = CallbackObserver<PowerStatus, const PowerStatus *>(this, &PowerStatus::updateStatus);
+
+        /// Whether we have a battery connected
+        bool hasBattery;
+        /// Battery voltage in mV, valid if haveBattery is true
+        int batteryVoltageMv;
+        /// Battery charge percentage, either read directly or estimated
+        uint8_t batteryChargePercent;
+        /// Whether USB is connected
+        bool hasUSB;
+        /// Whether we are charging the battery
+        bool isCharging;
+
+       public:
+
+        PowerStatus() {
+            statusType = STATUS_TYPE_POWER;
+        }
+        PowerStatus( bool hasBattery, bool hasUSB, bool isCharging, int batteryVoltageMv, uint8_t batteryChargePercent ) : Status()
+        {
+            this->hasBattery = hasBattery;
+            this->hasUSB = hasUSB;
+            this->isCharging = isCharging;
+            this->batteryVoltageMv = batteryVoltageMv;
+            this->batteryChargePercent = batteryChargePercent;
+        }
+        PowerStatus(const PowerStatus &);
+        PowerStatus &operator=(const PowerStatus &);
+
+        void observe(Observable<const PowerStatus *> *source)
+        {
+            statusObserver.observe(source);
+        }
+
+        bool getHasBattery() const
+        { 
+            return hasBattery; 
+        }
+
+        bool getHasUSB() const
+        {
+            return hasUSB;
+        }
+
+        bool getIsCharging() const
+        { 
+            return isCharging; 
+        }
+
+        int getBatteryVoltageMv() const
+        { 
+            return batteryVoltageMv; 
+        }
+
+        uint8_t getBatteryChargePercent() const
+        { 
+            return batteryChargePercent;
+        }
+
+        bool matches(const PowerStatus *newStatus) const
+        {
+            return (
+                newStatus->getHasBattery() != hasBattery ||
+                newStatus->getHasUSB() != hasUSB ||
+                newStatus->getBatteryVoltageMv() != batteryVoltageMv
+            );
+        }
+        int updateStatus(const PowerStatus *newStatus) {
+            // Only update the status if values have actually changed
+            bool isDirty;
+            {
+                isDirty = matches(newStatus);
+                initialized = true; 
+                hasBattery = newStatus->getHasBattery();
+                batteryVoltageMv = newStatus->getBatteryVoltageMv();
+                batteryChargePercent = newStatus->getBatteryChargePercent();
+                hasUSB = newStatus->getHasUSB();
+                isCharging = newStatus->getIsCharging();
+            }
+            if(isDirty) {
+                DEBUG_MSG("Battery %dmV %d%%\n", batteryVoltageMv, batteryChargePercent);
+                onNewStatus.notifyObservers(this);
+            }
+            return 0;
+        }
+
+    };
+
+}
+
+extern meshtastic::PowerStatus *powerStatus;

src/Status.h

@@ -0,0 +1,72 @@
+#pragma once
+
+#include "Observer.h"
+
+// Constants for the various status types, so we can tell subclass instances apart
+#define STATUS_TYPE_BASE 0
+#define STATUS_TYPE_POWER 1
+#define STATUS_TYPE_GPS 2
+#define STATUS_TYPE_NODE 3
+
+
+namespace meshtastic
+{
+
+    // A base class for observable status
+    class Status
+    {
+       protected:
+        // Allows us to observe an Observable
+        CallbackObserver<Status, const Status *> statusObserver = CallbackObserver<Status, const Status *>(this, &Status::updateStatus);
+        bool initialized = false;
+        // Workaround for no typeid support
+        int statusType;
+
+       public:
+        // Allows us to generate observable events
+        Observable<const Status *> onNewStatus;
+
+        // Enable polymorphism ?
+        virtual ~Status() = default;
+        
+        Status() {
+            if (!statusType)
+            {
+                statusType = STATUS_TYPE_BASE;
+            }
+        }
+
+        // Prevent object copy/move
+        Status(const Status &) = delete;
+        Status &operator=(const Status &) = delete;
+
+        // Start observing a source of data
+        void observe(Observable<const Status *> *source)
+        {
+            statusObserver.observe(source);
+        }
+
+        // Determines whether or not existing data matches the data in another Status instance
+        bool matches(const Status *otherStatus) const 
+        {
+            return true;
+        }
+
+        bool isInitialized() const
+        {
+            return initialized;
+        }
+
+        int getStatusType() const
+        {
+            return statusType;
+        }
+
+        // Called when the Observable we're observing generates a new notification
+        int updateStatus(const Status *newStatus) 
+        {
+            return 0;
+        }
+
+    };
+};

src/esp32/main-esp32.cpp

@@ -4,7 +4,6 @@
 #include "configuration.h"
 #include "esp_task_wdt.h"
 #include "main.h"
-#include "power.h"
 #include "sleep.h"
 #include "target_specific.h"
 #include "utils.h"
@@ -61,113 +60,6 @@ void getMacAddr(uint8_t *dmac)
     assert(esp_efuse_mac_get_default(dmac) == ESP_OK);
 }
 
-#ifdef TBEAM_V10
-
-// FIXME. nasty hack cleanup how we load axp192
-#undef AXP192_SLAVE_ADDRESS
-#include "axp20x.h"
-AXP20X_Class axp;
-bool pmu_irq = false;
-
-/// Reads power status to powerStatus singleton.
-//
-// TODO(girts): move this and other axp stuff to power.h/power.cpp.
-void readPowerStatus()
-{
-    powerStatus.haveBattery = axp.isBatteryConnect();
-    if (powerStatus.haveBattery) {
-        powerStatus.batteryVoltageMv = axp.getBattVoltage();
-        // If the AXP192 returns a valid battery percentage, use it
-        if (axp.getBattPercentage() >= 0) {
-            powerStatus.batteryChargePercent = axp.getBattPercentage();
-        } else {
-            // If the AXP192 returns a percentage less than 0, the feature is either not supported or there is an error
-            // In that case, we compute an estimate of the charge percent based on maximum and minimum voltages defined in power.h
-            powerStatus.batteryChargePercent = clamp((int)(((powerStatus.batteryVoltageMv - BAT_MILLIVOLTS_EMPTY) * 1e2) /
-                                                           (BAT_MILLIVOLTS_FULL - BAT_MILLIVOLTS_EMPTY)),
-                                                     0, 100);
-        }
-        DEBUG_MSG("Battery %dmV %d%%\n", powerStatus.batteryVoltageMv, powerStatus.batteryChargePercent);
-    }
-    powerStatus.usb = axp.isVBUSPlug();
-    powerStatus.charging = axp.isChargeing();
-}
-#endif // TBEAM_V10
-
-#ifdef AXP192_SLAVE_ADDRESS
-/**
- * Init the power manager chip
- *
- * axp192 power
-    DCDC1 0.7-3.5V @ 1200mA max -> OLED // If you turn this off you'll lose comms to the axp192 because the OLED and the axp192
- share the same i2c bus, instead use ssd1306 sleep mode DCDC2 -> unused DCDC3 0.7-3.5V @ 700mA max -> ESP32 (keep this on!) LDO1
- 30mA -> charges GPS backup battery // charges the tiny J13 battery by the GPS to power the GPS ram (for a couple of days), can
- not be turned off LDO2 200mA -> LORA LDO3 200mA -> GPS
- */
-void axp192Init()
-{
-    if (axp192_found) {
-        if (!axp.begin(Wire, AXP192_SLAVE_ADDRESS)) {
-            DEBUG_MSG("AXP192 Begin PASS\n");
-
-            // axp.setChgLEDMode(LED_BLINK_4HZ);
-            DEBUG_MSG("DCDC1: %s\n", axp.isDCDC1Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("DCDC2: %s\n", axp.isDCDC2Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("LDO2: %s\n", axp.isLDO2Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("LDO3: %s\n", axp.isLDO3Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("DCDC3: %s\n", axp.isDCDC3Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("Exten: %s\n", axp.isExtenEnable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("----------------------------------------\n");
-
-            axp.setPowerOutPut(AXP192_LDO2, AXP202_ON); // LORA radio
-            axp.setPowerOutPut(AXP192_LDO3, AXP202_ON); // GPS main power
-            axp.setPowerOutPut(AXP192_DCDC2, AXP202_ON);
-            axp.setPowerOutPut(AXP192_EXTEN, AXP202_ON);
-            axp.setPowerOutPut(AXP192_DCDC1, AXP202_ON);
-            axp.setDCDC1Voltage(3300); // for the OLED power
-
-            DEBUG_MSG("DCDC1: %s\n", axp.isDCDC1Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("DCDC2: %s\n", axp.isDCDC2Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("LDO2: %s\n", axp.isLDO2Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("LDO3: %s\n", axp.isLDO3Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("DCDC3: %s\n", axp.isDCDC3Enable() ? "ENABLE" : "DISABLE");
-            DEBUG_MSG("Exten: %s\n", axp.isExtenEnable() ? "ENABLE" : "DISABLE");
-
-            axp.setChargeControlCur(AXP1XX_CHARGE_CUR_1320MA); // actual limit (in HW) on the tbeam is 450mA
-#if 0
-
-      // Not connected
-      //val = 0xfc;
-      //axp._writeByte(AXP202_VHTF_CHGSET, 1, &val); // Set temperature protection
-
-      //not used
-      //val = 0x46;
-      //axp._writeByte(AXP202_OFF_CTL, 1, &val); // enable bat detection
-#endif
-            axp.debugCharging();
-
-#ifdef PMU_IRQ
-            pinMode(PMU_IRQ, INPUT);
-            attachInterrupt(
-                PMU_IRQ, [] { pmu_irq = true; }, FALLING);
-
-            axp.adc1Enable(AXP202_BATT_CUR_ADC1, 1);
-            axp.enableIRQ(AXP202_BATT_REMOVED_IRQ | AXP202_BATT_CONNECT_IRQ | AXP202_CHARGING_FINISHED_IRQ | AXP202_CHARGING_IRQ |
-                              AXP202_VBUS_REMOVED_IRQ | AXP202_VBUS_CONNECT_IRQ | AXP202_PEK_SHORTPRESS_IRQ,
-                          1);
-
-            axp.clearIRQ();
-#endif
-            readPowerStatus();
-        } else {
-            DEBUG_MSG("AXP192 Begin FAIL\n");
-        }
-    } else {
-        DEBUG_MSG("AXP192 not found\n");
-    }
-}
-#endif
-
 /*
 static void printBLEinfo() {
         int dev_num = esp_ble_get_bond_device_num();
@@ -193,10 +85,6 @@ void esp32Setup()
 
     // enableModemSleep();
 
-#ifdef AXP192_SLAVE_ADDRESS
-    axp192Init();
-#endif
-
 // Since we are turning on watchdogs rather late in the release schedule, we really don't want to catch any
 // false positives.  The wait-to-sleep timeout for shutting down radios is 30 secs, so pick 45 for now.
 #define APP_WATCHDOG_SECS 45
@@ -236,43 +124,4 @@ void esp32Loop()
 
     // for debug printing
     // radio.radioIf.canSleep();
-
-#ifdef PMU_IRQ
-    if (pmu_irq) {
-        pmu_irq = false;
-        axp.readIRQ();
-
-        DEBUG_MSG("pmu irq!\n");
-
-        if (axp.isChargingIRQ()) {
-            DEBUG_MSG("Battery start charging\n");
-        }
-        if (axp.isChargingDoneIRQ()) {
-            DEBUG_MSG("Battery fully charged\n");
-        }
-        if (axp.isVbusRemoveIRQ()) {
-            DEBUG_MSG("USB unplugged\n");
-        }
-        if (axp.isVbusPlugInIRQ()) {
-            DEBUG_MSG("USB plugged In\n");
-        }
-        if (axp.isBattPlugInIRQ()) {
-            DEBUG_MSG("Battery inserted\n");
-        }
-        if (axp.isBattRemoveIRQ()) {
-            DEBUG_MSG("Battery removed\n");
-        }
-        if (axp.isPEKShortPressIRQ()) {
-            DEBUG_MSG("PEK short button press\n");
-        }
-
-        readPowerStatus();
-        axp.clearIRQ();
-    }
-
-    if (powerStatus.haveBattery && !powerStatus.usb &&
-        axp.getBattVoltage() < MIN_BAT_MILLIVOLTS) // If we have a battery at all and it is less than 10% full, force deep sleep
-        powerFSM.trigger(EVENT_LOW_BATTERY);
-
-#endif // T_BEAM_V10
 }

src/gps/GPS.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "Observer.h"
+#include "GPSStatus.h"
 #include "PeriodicTask.h"
 #include "sys/time.h"
 
@@ -40,6 +41,8 @@ class GPS : public Observable<void *>
 
     virtual ~GPS() {}
 
+    Observable<const meshtastic::GPSStatus *> newStatus;
+
     /**
      * Returns true if we succeeded
      */

src/gps/NEMAGPS.cpp

@@ -65,5 +65,9 @@ void NEMAGPS::loop()
             if (hasValidLocation)
                 notifyObservers(NULL);
         }
+
+        // Notify any status instances that are observing us
+        const meshtastic::GPSStatus status = meshtastic::GPSStatus(hasLock(), isConnected, latitude, longitude, altitude, dop);
+        newStatus.notifyObservers(&status);
     }
 }

src/gps/UBloxGPS.cpp

@@ -116,7 +116,6 @@ The Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of s
         longitude = ublox.getLongitude(0);
         altitude = ublox.getAltitude(0) / 1000; // in mm convert to meters
         dop = ublox.getPDOP(0); // PDOP (an accuracy metric) is reported in 10^2 units so we have to scale down when we use it
-        DEBUG_MSG("new gps pos lat=%f, lon=%f, alt=%d, pdop=%f\n", latitude * 1e-7, longitude * 1e-7, altitude, dop * 1e-2);
 
         // bogus lat lon is reported as 0 or 0 (can be bogus just for one)
         // Also: apparently when the GPS is initially reporting lock it can output a bogus latitude > 90 deg!
@@ -129,6 +128,10 @@ The Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of s
     } else // we didn't get a location update, go back to sleep and hope the characters show up
         wantNewLocation = true;
 
+    // Notify any status instances that are observing us
+    const meshtastic::GPSStatus status = meshtastic::GPSStatus(hasLock(), isConnected, latitude, longitude, altitude, dop);
+    newStatus.notifyObservers(&status);
+
     // 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);

src/main.cpp

@@ -56,8 +56,14 @@
 // We always create a screen object, but we only init it if we find the hardware
 meshtastic::Screen screen(SSD1306_ADDRESS);
 
-// Global power status singleton
-meshtastic::PowerStatus powerStatus;
+// Global power status
+meshtastic::PowerStatus *powerStatus = new meshtastic::PowerStatus();
+
+// Global GPS status
+meshtastic::GPSStatus *gpsStatus = new meshtastic::GPSStatus();
+
+// Global Node status
+meshtastic::NodeStatus *nodeStatus = new meshtastic::NodeStatus();
 
 bool ssd1306_found;
 bool axp192_found;
@@ -121,7 +127,7 @@ static uint32_t ledBlinker()
     setLed(ledOn);
 
     // have a very sparse duty cycle of LED being on, unless charging, then blink 0.5Hz square wave rate to indicate that
-    return powerStatus.charging ? 1000 : (ledOn ? 2 : 1000);
+    return powerStatus->getIsCharging() ? 1000 : (ledOn ? 2 : 1000);
 }
 
 Periodic ledPeriodic(ledBlinker);
@@ -223,6 +229,10 @@ void setup()
         ssd1306_found = false; // forget we even have the hardware
 
     esp32Setup();
+    power = new Power();
+    power->setup();
+    power->setStatusHandler(powerStatus);
+    powerStatus->observe(&power->newStatus);
 #endif
 
 #ifdef NRF52_SERIES
@@ -253,9 +263,10 @@ void setup()
     gps = new NEMAGPS();
     gps->setup();
 #endif
+    gpsStatus->observe(&gps->newStatus);
+    nodeStatus->observe(&nodeDB.newStatus);
 
     service.init();
-
 #ifndef NO_ESP32
     // Must be after we init the service, because the wifi settings are loaded by NodeDB (oops)
     initWifi();
@@ -295,6 +306,7 @@ void setup()
     // This must be _after_ service.init because we need our preferences loaded from flash to have proper timeout values
     PowerFSM_setup(); // we will transition to ON in a couple of seconds, FIXME, only do this for cold boots, not waking from SDS
 
+
     // setBluetoothEnable(false); we now don't start bluetooth until we enter the proper state
     setCPUFast(false); // 80MHz is fine for our slow peripherals
 }
@@ -340,6 +352,7 @@ void loop()
 
 #ifndef NO_ESP32
     esp32Loop();
+    power->loop();
 #endif
 
 #ifdef BUTTON_PIN
@@ -365,9 +378,8 @@ void loop()
 #endif
 
     // Update the screen last, after we've figured out what to show.
-    screen.debug()->setNodeNumbersStatus(nodeDB.getNumOnlineNodes(), nodeDB.getNumNodes());
     screen.debug()->setChannelNameStatus(channelSettings.name);
-    screen.debug()->setPowerStatus(powerStatus);
+    //screen.debug()->setPowerStatus(powerStatus);
 
     // No GPS lock yet, let the OS put the main CPU in low power mode for 100ms (or until another interrupt comes in)
     // i.e. don't just keep spinning in loop as fast as we can.

src/main.h

@@ -1,6 +1,9 @@
 #pragma once
 
 #include "screen.h"
+#include "PowerStatus.h"
+#include "GPSStatus.h"
+#include "NodeStatus.h"
 
 extern bool axp192_found;
 extern bool ssd1306_found;
@@ -9,6 +12,11 @@ extern bool isUSBPowered;
 
 // Global Screen singleton.
 extern meshtastic::Screen screen;
+//extern Observable<meshtastic::PowerStatus> newPowerStatus; //TODO: move this to main-esp32.cpp somehow or a helper class
+
+//extern meshtastic::PowerStatus *powerStatus;
+//extern meshtastic::GPSStatus *gpsStatus;
+//extern meshtastic::NodeStatusHandler *nodeStatusHandler;
 
 // Return a human readable string of the form "Meshtastic_ab13"
 const char *getDeviceName();

src/mesh/MeshService.cpp

@@ -303,7 +303,7 @@ int MeshService::onGPSChanged(void *unused)
     }
 
     // Include our current battery voltage in our position announcement
-    pos.battery_level = powerStatus.batteryChargePercent;
+    pos.battery_level = powerStatus->getBatteryChargePercent();
     updateBatteryLevel(pos.battery_level);
 
     // We limit our GPS broadcasts to a max rate

src/mesh/NodeDB.cpp

@@ -342,8 +342,7 @@ void NodeDB::updateFrom(const MeshPacket &mp)
         int oldNumNodes = *numNodes;
         NodeInfo *info = getOrCreateNode(mp.from);
 
-        if (oldNumNodes != *numNodes)
-            updateGUI = true; // we just created a nodeinfo
+        notifyObservers();
 
         if (mp.rx_time) {              // if the packet has a valid timestamp use it to update our last_seen
             info->has_position = true; // at least the time is valid

src/mesh/NodeDB.h

@@ -2,9 +2,11 @@
 
 #include <Arduino.h>
 #include <assert.h>
+#include "Observer.h"
 
 #include "MeshTypes.h"
 #include "mesh-pb-constants.h"
+#include "NodeStatus.h"
 
 extern DeviceState devicestate;
 extern MyNodeInfo &myNodeInfo;
@@ -32,6 +34,7 @@ class NodeDB
     bool updateGUI = false;            // we think the gui should definitely be redrawn, screen will clear this once handled
     NodeInfo *updateGUIforNode = NULL; // if currently showing this node, we think you should update the GUI
     bool updateTextMessage = false;    // if true, the GUI should show a new text message
+    Observable<const meshtastic::NodeStatus *> newStatus;
 
     /// don't do mesh based algoritm for node id assignment (initially)
     /// instead just store in flash - possibly even in the initial alpha release do this hack
@@ -91,6 +94,13 @@ class NodeDB
     /// Find a node in our DB, create an empty NodeInfo if missing
     NodeInfo *getOrCreateNode(NodeNum n);
 
+    /// Notify observers of changes to the DB
+    void notifyObservers() {
+        // Notify observers of the current node state
+        const meshtastic::NodeStatus status = meshtastic::NodeStatus(getNumOnlineNodes(), getNumNodes());
+        newStatus.notifyObservers(&status);
+    }
+
     /// read our db from flash
     void loadFromDisk();
 

src/power.h

@@ -1,4 +1,6 @@
 #pragma once
+#include "PeriodicTask.h"
+#include "PowerStatus.h"
 
 /**
  * Per @spattinson
@@ -13,23 +15,26 @@
 #define BAT_MILLIVOLTS_FULL 4100
 #define BAT_MILLIVOLTS_EMPTY 3500
 
-namespace meshtastic
+class Power : public PeriodicTask
 {
 
-/// Describes the state of the power system.
-struct PowerStatus {
-    /// Whether we have a battery connected
-    bool haveBattery;
-    /// Battery voltage in mV, valid if haveBattery is true
-    int batteryVoltageMv;
-    /// Battery charge percentage, either read directly or estimated
-    int batteryChargePercent;
-    /// Whether USB is connected
-    bool usb;
-    /// Whether we are charging the battery
-    bool charging;
+   public:
+
+    Observable<const meshtastic::PowerStatus *> newStatus;
+
+    void readPowerStatus();
+    void loop();
+    virtual bool setup();
+    virtual void doTask();
+    void setStatusHandler(meshtastic::PowerStatus *handler)
+    {
+        statusHandler = handler;
+    }
+    
+   protected:
+    meshtastic::PowerStatus *statusHandler;
+    virtual void axp192Init();
+
 };
 
-} // namespace meshtastic
-
-extern meshtastic::PowerStatus powerStatus;
+extern Power *power;

src/screen.cpp

@@ -42,7 +42,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #endif
 #define SCREEN_HEIGHT 64
 #define TRANSITION_FRAMERATE 30 // fps
-#define IDLE_FRAMERATE 10       // in fps
+#define IDLE_FRAMERATE 1        // in fps
 #define COMPASS_DIAM 44
 
 #define NUM_EXTRA_FRAMES 2 // text message and debug frame
@@ -55,7 +55,8 @@ static FrameCallback normalFrames[MAX_NUM_NODES + NUM_EXTRA_FRAMES];
 static uint32_t targetFramerate = IDLE_FRAMERATE;
 static char btPIN[16] = "888888";
 
-uint8_t imgBattery[16] = {0xFF, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0xE7, 0x3C};
+uint8_t imgBattery[16] = { 0xFF, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0x81, 0xE7, 0x3C };
+static bool heartbeat = false;
 
 static void drawBootScreen(OLEDDisplay *display, OLEDDisplayUiState *state, int16_t x, int16_t y)
 {
@@ -143,52 +144,54 @@ static void drawColumns(OLEDDisplay *display, int16_t x, int16_t y, const char *
     }
 }
 
-/// Draw a series of fields in a row, wrapping to multiple rows if needed
-/// @return the max y we ended up printing to
-static uint32_t drawRows(OLEDDisplay *display, int16_t x, int16_t y, const char **fields)
-{
-    // The coordinates define the left starting point of the text
-    display->setTextAlignment(TEXT_ALIGN_LEFT);
+#if 0
+    /// Draw a series of fields in a row, wrapping to multiple rows if needed
+    /// @return the max y we ended up printing to
+    static uint32_t drawRows(OLEDDisplay *display, int16_t x, int16_t y, const char **fields)
+    {
+        // The coordinates define the left starting point of the text
+        display->setTextAlignment(TEXT_ALIGN_LEFT);
 
-    const char **f = fields;
-    int xo = x, yo = y;
-    const int COLUMNS = 2; // hardwired for two columns per row....
-    int col = 0;           // track which column we are on
-    while (*f) {
-        display->drawString(xo, yo, *f);
-        xo += SCREEN_WIDTH / COLUMNS;
-        // Wrap to next row, if needed.
-        if (++col >= COLUMNS) {
-            xo = x;
-            yo += FONT_HEIGHT;
-            col = 0;
+        const char **f = fields;
+        int xo = x, yo = y;
+        const int COLUMNS = 2; // hardwired for two columns per row....
+        int col = 0;           // track which column we are on
+        while (*f) {
+            display->drawString(xo, yo, *f);
+            xo += SCREEN_WIDTH / COLUMNS;
+            // Wrap to next row, if needed.
+            if (++col >= COLUMNS) {
+                xo = x;
+                yo += FONT_HEIGHT;
+                col = 0;
+            }
+            f++;
+        }
+        if (col != 0) {
+            // Include last incomplete line in our total.
+            yo += FONT_HEIGHT;
         }
-        f++;
-    }
-    if (col != 0) {
-        // Include last incomplete line in our total.
-        yo += FONT_HEIGHT;
-    }
 
-    return yo;
-}
+        return yo;
+    }
+#endif
 
 // Draw power bars or a charging indicator on an image of a battery, determined by battery charge voltage or percentage.
-static void drawBattery(OLEDDisplay *display, int16_t x, int16_t y, uint8_t *imgBuffer, PowerStatus *powerStatus)
+static void drawBattery(OLEDDisplay *display, int16_t x, int16_t y, uint8_t *imgBuffer, const PowerStatus *powerStatus) 
 {
-    static const uint8_t powerBar[3] = {0x81, 0xBD, 0xBD};
-    static const uint8_t lightning[8] = {0xA1, 0xA1, 0xA5, 0xAD, 0xB5, 0xA5, 0x85, 0x85};
+    static const uint8_t powerBar[3] = { 0x81, 0xBD, 0xBD };
+    static const uint8_t lightning[8] = { 0xA1, 0xA1, 0xA5, 0xAD, 0xB5, 0xA5, 0x85, 0x85 };
     // Clear the bar area on the battery image
     for (int i = 1; i < 14; i++) {
         imgBuffer[i] = 0x81;
     }
     // If charging, draw a charging indicator
-    if (powerStatus->charging) {
+    if (powerStatus->getIsCharging()) {
         memcpy(imgBuffer + 3, lightning, 8);
         // If not charging, Draw power bars
     } else {
         for (int i = 0; i < 4; i++) {
-            if (powerStatus->batteryChargePercent >= 25 * i)
+            if(powerStatus->getBatteryChargePercent() >= 25 * i) 
                 memcpy(imgBuffer + 1 + (i * 3), powerBar, 3);
         }
     }
@@ -196,47 +199,47 @@ static void drawBattery(OLEDDisplay *display, int16_t x, int16_t y, uint8_t *img
 }
 
 // Draw nodes status
-static void drawNodes(OLEDDisplay *display, int16_t x, int16_t y, int nodesOnline, int nodesTotal)
+static void drawNodes(OLEDDisplay *display, int16_t x, int16_t y, NodeStatus *nodeStatus) 
 {
     char usersString[20];
-    sprintf(usersString, "%d/%d", nodesOnline, nodesTotal);
+    sprintf(usersString, "%d/%d", nodeStatus->getNumOnline(), nodeStatus->getNumTotal());
     display->drawFastImage(x, y, 8, 8, imgUser);
     display->drawString(x + 10, y - 2, usersString);
 }
 
 // Draw GPS status summary
-static void drawGPS(OLEDDisplay *display, int16_t x, int16_t y, GPS *gps)
+static void drawGPS(OLEDDisplay *display, int16_t x, int16_t y, const GPSStatus *gps)
 {
-    if (!gps->isConnected) {
+    if (!gps->getIsConnected()) {
         display->drawString(x, y - 2, "No GPS");
         return;
     }
-    display->drawFastImage(x, y, 6, 8, gps->hasLock() ? imgPositionSolid : imgPositionEmpty);
-    if (!gps->hasLock()) {
+    display->drawFastImage(x, y, 6, 8, gps->getHasLock() ? imgPositionSolid : imgPositionEmpty);
+    if (!gps->getHasLock()) {
         display->drawString(x + 8, y - 2, "No sats");
         return;
     }
-    if (gps->dop <= 100) {
+    if (gps->getDOP() <= 100) {
         display->drawString(x + 8, y - 2, "Ideal");
         return;
     }
-    if (gps->dop <= 200) {
+    if (gps->getDOP() <= 200) {
         display->drawString(x + 8, y - 2, "Exc.");
         return;
     }
-    if (gps->dop <= 500) {
+    if (gps->getDOP() <= 500) {
         display->drawString(x + 8, y - 2, "Good");
         return;
     }
-    if (gps->dop <= 1000) {
+    if (gps->getDOP() <= 1000) {
         display->drawString(x + 8, y - 2, "Mod.");
         return;
     }
-    if (gps->dop <= 2000) {
+    if (gps->getDOP() <= 2000) {
         display->drawString(x + 8, y - 2, "Fair");
         return;
     }
-    if (gps->dop > 0) {
+    if (gps->getDOP() > 0) {
         display->drawString(x + 8, y - 2, "Poor");
         return;
     }
@@ -576,6 +579,11 @@ void Screen::setup()
     // twice initially.
     ui.update();
     ui.update();
+
+    // Subscribe to status updates
+    powerStatusObserver.observe(&powerStatus->onNewStatus);
+    gpsStatusObserver.observe(&gpsStatus->onNewStatus);
+    nodeStatusObserver.observe(&nodeStatus->onNewStatus);
 }
 
 void Screen::doTask()
@@ -637,14 +645,7 @@ void Screen::doTask()
     // While showing the bootscreen or Bluetooth pair screen all of our
     // standard screen switching is stopped.
     if (showingNormalScreen) {
-        // TODO(girts): decouple nodeDB from screen.
-        // standard screen loop handling ehre
-        // If the # nodes changes, we need to regen our list of screens
-        if (nodeDB.updateGUI || nodeDB.updateTextMessage) {
-            setFrames();
-            nodeDB.updateGUI = false;
-            nodeDB.updateTextMessage = false;
-        }
+        // standard screen loop handling here
     }
 
     ui.update();
@@ -669,8 +670,8 @@ void Screen::setFrames()
     DEBUG_MSG("showing standard frames\n");
     showingNormalScreen = true;
 
-    size_t numnodes = nodeDB.getNumNodes();
     // We don't show the node info our our node (if we have it yet - we should)
+    size_t numnodes = nodeStatus->getNumTotal();
     if (numnodes > 0)
         numnodes--;
 
@@ -750,20 +751,24 @@ void DebugInfo::drawFrame(OLEDDisplay *display, OLEDDisplayUiState *state, int16
         snprintf(channelStr, sizeof(channelStr), "#%s", channelName.c_str());
 
         // Display power status
-        if (powerStatus.haveBattery)
-            drawBattery(display, x, y + 2, imgBattery, &powerStatus);
+        if (powerStatus->getHasBattery())
+            drawBattery(display, x, y + 2, imgBattery, powerStatus);
         else
-            display->drawFastImage(x, y + 2, 16, 8, powerStatus.usb ? imgUSB : imgPower);
+            display->drawFastImage(x, y + 2, 16, 8, powerStatus->getHasUSB() ? imgUSB : imgPower);
         // Display nodes status
-        drawNodes(display, x + (SCREEN_WIDTH * 0.25), y + 2, nodesOnline, nodesTotal);
+        drawNodes(display, x + (SCREEN_WIDTH * 0.25), y + 2, nodeStatus);
         // Display GPS status
-        drawGPS(display, x + (SCREEN_WIDTH * 0.66), y + 2, gps);
+        drawGPS(display, x + (SCREEN_WIDTH * 0.66), y + 2, gpsStatus);
     }
 
-    const char *fields[] = {channelStr, nullptr};
-    uint32_t yo = drawRows(display, x, y + FONT_HEIGHT, fields);
+    display->drawString(x, y + FONT_HEIGHT, channelStr);
 
-    display->drawLogBuffer(x, yo);
+    display->drawLogBuffer(x, y + (FONT_HEIGHT * 2));
+
+    /* Display a heartbeat pixel that blinks every time the frame is redrawn
+    if(heartbeat) display->setPixel(0, 0);
+    heartbeat = !heartbeat;
+    */
 }
 
 // adjust Brightness cycle trough 1 to 254 as long as attachDuringLongPress is true
@@ -781,4 +786,15 @@ void Screen::adjustBrightness()
     dispdev.setBrightness(brightness);
 }
 
+int Screen::handleStatusUpdate(const Status *arg) {
+    DEBUG_MSG("Screen got status update %d\n", arg->getStatusType());
+    switch(arg->getStatusType())
+    {
+        case STATUS_TYPE_NODE:
+            setFrames();
+            break;
+    }
+    setPeriod(1); // Update the screen right away
+    return 0;
+}
 } // namespace meshtastic

src/screen.h

@@ -13,7 +13,10 @@
 #include "PeriodicTask.h"
 #include "TypedQueue.h"
 #include "lock.h"
-#include "power.h"
+#include "PowerStatus.h"
+#include "GPSStatus.h"
+#include "NodeStatus.h"
+#include "Observer.h"
 #include <string>
 
 namespace meshtastic
@@ -29,14 +32,6 @@ class DebugInfo
     DebugInfo(const DebugInfo &) = delete;
     DebugInfo &operator=(const DebugInfo &) = delete;
 
-    /// Sets user statistics.
-    void setNodeNumbersStatus(int online, int total)
-    {
-        LockGuard guard(&lock);
-        nodesOnline = online;
-        nodesTotal = total;
-    }
-
     /// Sets the name of the channel.
     void setChannelNameStatus(const char *name)
     {
@@ -44,25 +39,6 @@ class DebugInfo
         channelName = name;
     }
 
-    /// Sets battery/charging/etc status.
-    //
-    void setPowerStatus(const PowerStatus &status)
-    {
-        LockGuard guard(&lock);
-        powerStatus = status;
-    }
-
-    /// Sets GPS status.
-    //
-    // If this function never gets called, we assume GPS does not exist on this
-    // device.
-    // TODO(girts): figure out what the format should be.
-    void setGPSStatus(const char *status)
-    {
-        LockGuard guard(&lock);
-        gpsStatus = status;
-    }
-
   private:
     friend Screen;
 
@@ -71,15 +47,8 @@ class DebugInfo
     /// Renders the debug screen.
     void drawFrame(OLEDDisplay *display, OLEDDisplayUiState *state, int16_t x, int16_t y);
 
-    int nodesOnline = 0;
-    int nodesTotal = 0;
-
-    PowerStatus powerStatus;
-
     std::string channelName;
 
-    std::string gpsStatus;
-
     /// Protects all of internal state.
     Lock lock;
 };
@@ -93,6 +62,10 @@ class DebugInfo
 // simultaneously).
 class Screen : public PeriodicTask
 {
+    CallbackObserver<Screen, const Status *> powerStatusObserver = CallbackObserver<Screen, const Status *>(this, &Screen::handleStatusUpdate);
+    CallbackObserver<Screen, const Status *> gpsStatusObserver = CallbackObserver<Screen, const Status *>(this, &Screen::handleStatusUpdate);
+    CallbackObserver<Screen, const Status *> nodeStatusObserver = CallbackObserver<Screen, const Status *>(this, &Screen::handleStatusUpdate);
+
   public:
     Screen(uint8_t address, int sda = -1, int scl = -1);
 
@@ -189,6 +162,8 @@ class Screen : public PeriodicTask
     // Use this handle to set things like battery status, user count, GPS status, etc.
     DebugInfo *debug() { return &debugInfo; }
 
+    int handleStatusUpdate(const meshtastic::Status *arg);
+
   protected:
     /// Updates the UI.
     //