Transmit last temperature time

include/storage.h

@@ -17,6 +17,8 @@ constexpr size_t rtcStorageSize = 7600;
 constexpr size_t maxEepromSize = 13350;
 constexpr size_t eepromSize = 13350;
 
+constexpr size_t totalStorageSize = rtcStorageSize + eepromSize;
+
 // The minimum temperature to store, in millidegrees celcius
 // True minimum will be higher by 1°, since two values are reserved 
 constexpr long temperatureShiftForStorage = -40000;
@@ -44,6 +46,8 @@ uint16_t getNumberOfMeasurements();
 
 uint8_t getLastTemperature(uint8_t sensorIndex);
 
+uint16_t getTimeSinceValidTemperature(uint8_t sensorIndex);
+
 uint16_t getRecordedBytesAtOffset(uint8_t* buffer, uint16_t offset, uint16_t count);
 
 void discardAllRecordedBytes();

src/bluetooth.cpp

@@ -30,7 +30,7 @@ uint8_t* bluetoothResponse;
 size_t bluetoothDataCount = 0;
 
 void bluetoothStartAdvertising();
-void bluetoothDidReceiveData(uint8_t* buffer, size_t count);
+void bluetoothDidReceiveData(uint8_t* buffer, uint16_t count);
 
 class BluetoothConnection: public BLEServerCallbacks {
 
@@ -215,17 +215,9 @@ uint16_t readNumberFromReceivedBuffer(uint8_t* buffer) {
     return *((uint16_t*) buffer + 1);
 }
 
-void bluetoothDidReceiveData(uint8_t* buffer, size_t count) {
-    if (count < 1) {
-        setResponseWithoutData(BluetoothResponse::invalidCommand);
-        return;
-    }
-
-    uint32_t currentTime;
+void fillInfo() {
     uint16_t value;
-    BluetoothRequest request = static_cast<BluetoothRequest>(buffer[0]);
-    switch (request) {
-    case BluetoothRequest::getInfo:
+
     // BluetoothResponse::success
     setResponse(BluetoothResponse::success);
 
@@ -255,7 +247,7 @@ void bluetoothDidReceiveData(uint8_t* buffer, size_t count) {
     bluetoothDataCount += sizeof(uint16_t);
 
     // the number of seconds since power on as a uint32_t (4 bytes)
-        currentTime = time(NULL);
+    uint32_t currentTime = time(NULL);
     memcpy(bluetoothDataBuffer + bluetoothDataCount, &currentTime, sizeof(uint32_t));
     bluetoothDataCount += sizeof(uint32_t);
 
@@ -270,31 +262,74 @@ void bluetoothDidReceiveData(uint8_t* buffer, size_t count) {
     bluetoothDataCount += TEMPERATURE_SENSOR_ADDRESS_SIZE;
     copySensorAddress(1, bluetoothDataBuffer + bluetoothDataCount);
     bluetoothDataCount += TEMPERATURE_SENSOR_ADDRESS_SIZE;
+
+    // Time since measurement of sensor 0
+    value = getTimeSinceValidTemperature(0);
+    memcpy(bluetoothDataBuffer + bluetoothDataCount, &value, sizeof(uint16_t));
+    bluetoothDataCount += sizeof(uint16_t);
+
+    // Time since measurement of sensor 1
+    value = getTimeSinceValidTemperature(1);
+    memcpy(bluetoothDataBuffer + bluetoothDataCount, &value, sizeof(uint16_t));
+    bluetoothDataCount += sizeof(uint16_t);
+
+    value = totalStorageSize;
+    memcpy(bluetoothDataBuffer + bluetoothDataCount, &value, sizeof(uint16_t));
+    bluetoothDataCount += sizeof(uint16_t);
+}
+
+void getRecordingData(uint8_t* buffer, uint16_t count) {
+    if (count != 2 * sizeof(uint16_t)) {
+        setResponseWithoutData(BluetoothResponse::invalidCommand);
+        return;
+    }
+    uint16_t byteCount;
+    memcpy(&byteCount, buffer, sizeof(uint16_t));
+    if (byteCount > bluetoothMaxDataSize) {
+        setResponseWithoutData(BluetoothResponse::responseTooLarge);
+        return;
+    }
+
+    uint16_t byteOffset;
+    memcpy(&byteOffset, buffer + sizeof(uint16_t), sizeof(uint16_t));
+    
+    bluetoothDataCount = getRecordedBytesAtOffset(bluetoothDataBuffer, byteOffset, byteCount);
+}
+
+void clearRecordingBuffer(uint8_t* buffer, uint16_t count) {
+    if (count != sizeof(uint16_t)) {
+        setResponseWithoutData(BluetoothResponse::invalidCommand);
+        return;
+    }
+    uint16_t byteCount;
+    memcpy(&byteCount, buffer, sizeof(uint16_t));
+    if (byteCount != getTotalNumberOfStoredBytes()) {
+        setResponseWithoutData(BluetoothResponse::invalidNumberOfBytesToDelete);
+        return;
+    }
+
+    discardAllRecordedBytes();
+    setResponseWithoutData(BluetoothResponse::success);
+}
+
+void bluetoothDidReceiveData(uint8_t* buffer, uint16_t count) {
+    if (count < 1) {
+        setResponseWithoutData(BluetoothResponse::invalidCommand);
+        return;
+    }
+
+    BluetoothRequest request = static_cast<BluetoothRequest>(buffer[0]);
+    switch (request) {
+    case BluetoothRequest::getInfo:
+        fillInfo();
         break;
 
     case BluetoothRequest::clearRecordingBuffer:
-        memcpy(&count, buffer + 1, sizeof(uint16_t));
-        if (count != getTotalNumberOfStoredBytes()) {
-            setResponseWithoutData(BluetoothResponse::invalidNumberOfBytesToDelete);
-        } else {
-            discardAllRecordedBytes();
-            setResponseWithoutData(BluetoothResponse::success);
-        }
+        clearRecordingBuffer(buffer + sizeof(uint8_t), count - sizeof(uint8_t));
         break;
 
     case BluetoothRequest::getRecordingData:
-        if (count != sizeof(uint16_t) + sizeof(uint8_t)) {
-            setResponseWithoutData(BluetoothResponse::invalidCommand);
-            break;
-        }
-        memcpy(&value, buffer + sizeof(uint8_t)                   , sizeof(uint16_t));
-        memcpy(&count, buffer + sizeof(uint8_t) + sizeof(uint16_t), sizeof(uint16_t));
-        if (count > bluetoothMaxDataSize) {
-            setResponseWithoutData(BluetoothResponse::responseTooLarge);
-            break;
-        }
-        count = getRecordedBytesAtOffset(bluetoothDataBuffer, value, count);
-        bluetoothDataCount = count;
+        getRecordingData(buffer + sizeof(uint8_t), count - sizeof(uint8_t));
         break;
     
     default:

src/main.cpp

@@ -134,7 +134,7 @@ void loop() {
         setNextTemperatureMeasurementInterval();
     }
 
-    if (wakeupButtonIsPressed()) {
+    if (wakeupButtonIsPressed() || bluetoothIsConnected()) {
         bluetoothConfigure(); // Only done once internally
         updateStayAwakeTime();
     }
@@ -146,5 +146,7 @@ void loop() {
         // May return, if less then one second to wait
         // Otherwise control flow starts with setup() again
         deepSleepUntilNextTemperatureMeasurement();
+    } else {
+        delay(100);
     }
 }

src/storage.cpp

@@ -19,13 +19,14 @@ RTC_DATA_ATTR bool isFirstRunAfterPowerOn = true;
 
 // Keeps the last valid temperatures for each sensor
 RTC_DATA_ATTR Temperature lastTemperatures[temperatureSensorCount];
+RTC_DATA_ATTR uint32_t lastValidTemperatureTime[temperatureSensorCount];
 
 bool didSetupEEPROM = false;
 
 // On first boot, this is set to true; Afterwards it's remembered to be false
 RTC_DATA_ATTR bool eepromIsConsideredEmpty = true;
 
-constexpr uint16_t eepromOffset = 2; // Size of uint16
+constexpr uint16_t eepromOffset = sizeof(uint16_t);
 constexpr uint16_t eepromDataSize = eepromSize - eepromOffset;
 
 void setupEEPROMIfNeeded() {
@@ -46,6 +47,7 @@ void resetLastMeasurements() {
     for (uint8_t index = 0; index < temperatureSensorCount; index += 1) {
         lastTemperatures[index].status == TemperatureStatus::sensorNotFound;
         lastTemperatures[index].value = 0;
+        lastValidTemperatureTime[index] = 0;
     }
 }
 
@@ -146,6 +148,7 @@ void saveTemperatures(Temperature* temperatures) {
             if (temperatures[sensorIndex].status == TemperatureStatus::temperatureIsValid) {
                 // Only update if temperature is valid
                 lastTemperatures[sensorIndex] = temperatures[sensorIndex];
+                lastValidTemperatureTime[sensorIndex] = time(NULL);
             }
         }
     } else {
@@ -169,6 +172,7 @@ void saveTemperatures(Temperature* temperatures) {
             if (temperatures[index].status == TemperatureStatus::temperatureIsValid) {
                 // Only update if temperature is valid
                 lastTemperatures[index] = temperatures[index];
+                lastValidTemperatureTime[index] = time(NULL);
             }
         }
         // Ensure storage with uneven number of sensors
@@ -196,6 +200,10 @@ uint8_t getLastTemperature(uint8_t sensorIndex) {
     return byteForAbsoluteTemperature(lastTemperatures[sensorIndex].value);
 }
 
+uint16_t getTimeSinceValidTemperature(uint8_t sensorIndex) {
+    return time(NULL) - lastValidTemperatureTime[sensorIndex];
+}
+
 uint16_t getRecordedBytesAtOffset(uint8_t* buffer, uint16_t offset, uint16_t count) {
     // TODO: Check limits
     uint16_t eepromByteCount = getNumberOfBytesStoredInEEPROM();
@@ -221,5 +229,4 @@ void discardAllRecordedBytes() {
     dataIndex = 0;
     numberOfMeasurements = 0;
     resetLastMeasurements();
-    
 }