DIO0 and DIO1 optional and deep sleep for ESP device

README.md

@@ -105,6 +105,73 @@ For example, this could look like this:
 	  	.DIO2 = RFM_DIO2,
 	  	.DIO5 = RFM_DIO5
   	}; 
+All unused pin should be set to -1. All DIO pins are optional. RST could be set to -1 if connected to the reset pin of ESP8266.
+Using DIO0 and DIO1 makes the sending and receiving packet slighly faster.
+
+Deep sleep
+-----------
+For ESP device, when deep sleep is called, all the memory is flush execpt the memory explicitly put in RTC memory.
+In order to not loose LoRa session information and thus having to rejoin the LoRaWAN network after deep sleep, the following
+variable needs save on RTC RAM:
+
+	lora.DevEUI
+	lora.AppEUI
+	lora.AppKey
+	lora.DevNonce
+	lora.AppNonce
+	lora.NetID
+	lora.Address_Tx
+	lora.NwkSKey
+	lora.AppSKey
+	lora.Frame_Counter_Tx
+	lora.LoRa_Settings
+
+Different strategies could be used to save those variables. It is suggested to create a struct as follows and to save that structure
+on RTC memory:
+
+	struct RTCRAM {
+		unsigned char DevEUI[8];
+		unsigned char AppEUI[8];
+		unsigned char AppKey[16];
+		unsigned char DevNonce[2];
+		unsigned char AppNonce[3];
+		unsigned char NetID[3];
+		unsigned char Address_Tx[4];
+		unsigned char NwkSKey[16];
+		unsigned char AppSKey[16];
+		unsigned int Frame_Counter_Tx;
+		sSettings LoRa_Settings;
+	};
+	RTCRAM rtcRAM;
+
+Once the RTC memory are loaded after deep sleep, the variable can be parse to the LoRaWANClass as follow:
+
+	memcpy(lora.DevEUI, rtcRAM.DevEUI, sizeof(rtcRAM.DevEUI));
+	memcpy(lora.AppEUI, rtcRAM.AppEUI, sizeof(rtcRAM.AppEUI));
+	memcpy(lora.AppKey, rtcRAM.AppKey, sizeof(rtcRAM.AppKey));
+	memcpy(lora.DevNonce, rtcRAM.DevNonce, sizeof(rtcRAM.DevNonce));
+	memcpy(lora.AppNonce, rtcRAM.AppNonce, sizeof(rtcRAM.AppNonce));
+	memcpy(lora.NetID, rtcRAM.NetID, sizeof(rtcRAM.NetID));
+	memcpy(lora.Address_Tx, rtcRAM.Address_Tx, sizeof(rtcRAM.Address_Tx));
+	memcpy(lora.NwkSKey, rtcRAM.NwkSKey, sizeof(rtcRAM.NwkSKey));
+	memcpy(lora.AppSKey, rtcRAM.AppSKey, sizeof(rtcRAM.AppSKey));
+	memcpy(&lora.Frame_Counter_Tx, &rtcRAM.Frame_Counter_Tx, sizeof(rtcRAM.Frame_Counter_Tx));
+	memcpy(&lora.LoRa_Settings, &rtcRAM.LoRa_Settings, sizeof(rtcRAM.LoRa_Settings));
+
+The same strategy is used before calling deep sleep in order to save the updated LoRaWAN session on the RTCRAM structure:
+
+	memcpy(rtcRAM.DevEUI, lora.DevEUI, sizeof(rtcRAM.DevEUI));
+	memcpy(rtcRAM.AppEUI, lora.AppEUI, sizeof(rtcRAM.AppEUI));
+	memcpy(rtcRAM.AppKey, lora.AppKey, sizeof(rtcRAM.AppKey));
+	memcpy(rtcRAM.DevNonce, lora.DevNonce, sizeof(rtcRAM.DevNonce));
+	memcpy(rtcRAM.AppNonce, lora.AppNonce, sizeof(rtcRAM.AppNonce));
+	memcpy(rtcRAM.NetID, lora.NetID, sizeof(rtcRAM.NetID));
+	memcpy(rtcRAM.Address_Tx, lora.Address_Tx, sizeof(rtcRAM.Address_Tx));
+	memcpy(rtcRAM.NwkSKey, lora.NwkSKey, sizeof(rtcRAM.NwkSKey));
+	memcpy(rtcRAM.AppSKey, lora.AppSKey, sizeof(rtcRAM.AppSKey));
+	memcpy(&rtcRAM.Frame_Counter_Tx, &lora.Frame_Counter_Tx, sizeof(rtcRAM.Frame_Counter_Tx));
+	memcpy(&rtcRAM.LoRa_Settings, &lora.LoRa_Settings, sizeof(rtcRAM.LoRa_Settings));
+	memcpy(&rtcRAM.counter, &counter, sizeof(rtcRAM.counter));
 
 API
 --------

examples/class_a_otaa_esp_deepsleep/class_a_otaa_esp_deepsleep.ino

@@ -0,0 +1,205 @@
+/**
+ * Example of OTAA device with ESP8266 or ESP32 using deep sleep wihtout losing LoRaWAN settings.
+ * A minimum number of pin is also used in this example. For slighly faster processing,
+ * DIO0 and DIO1 should be used.
+ */
+#include <Arduino.h>
+#include <lorawan.h>
+
+// OTAA credentials
+const char *devEui = "0000000000000000";
+const char *appEui = "0000000000000000";
+const char *appKey = "00000000000000000000000000000000";
+
+unsigned int counter = 0; // message counter
+
+char myStr[50];
+char outStr[255];
+byte recvStatus = 0;
+
+const sRFM_pins RFM_pins = {
+    .CS = 15,
+    .RST = 2,
+    .DIO0 = -1,
+    .DIO1 = -1,
+    .DIO2 = -1,
+    .DIO5 = -1,
+};
+
+struct RTCRAM
+{
+    unsigned char DevEUI[8];
+    unsigned char AppEUI[8];
+    unsigned char AppKey[16];
+    unsigned char DevNonce[2];
+    unsigned char AppNonce[3];
+    unsigned char NetID[3];
+    unsigned char Address_Tx[4];
+    unsigned char NwkSKey[16];
+    unsigned char AppSKey[16];
+    unsigned int Frame_Counter_Tx;
+    sSettings LoRa_Settings;
+    unsigned int counter;
+};
+#if defined(ESP32)
+RTC_DATA_ATTR RTCRAM rtcRAM;
+#else
+RTCRAM rtcRAM;
+#endif
+
+void deepsleep(uint64_t us)
+{
+    Serial.println("We go to deep sleep");
+    delay(10);
+    lora.sleep();
+#if defined(ESP8266)
+    ESP.deepSleep(us, WAKE_RF_DISABLED);
+#elif defined(ESP32)
+    esp_sleep_enable_timer_wakeup(us);
+    esp_deep_sleep_start();
+#else
+    Serial.print("Deep sleep not supported by this example");
+#endif
+}
+
+void saveVariableRTC()
+{
+    memcpy(rtcRAM.DevEUI, lora.DevEUI, sizeof(rtcRAM.DevEUI));
+    memcpy(rtcRAM.AppEUI, lora.AppEUI, sizeof(rtcRAM.AppEUI));
+    memcpy(rtcRAM.AppKey, lora.AppKey, sizeof(rtcRAM.AppKey));
+    memcpy(rtcRAM.DevNonce, lora.DevNonce, sizeof(rtcRAM.DevNonce));
+    memcpy(rtcRAM.AppNonce, lora.AppNonce, sizeof(rtcRAM.AppNonce));
+    memcpy(rtcRAM.NetID, lora.NetID, sizeof(rtcRAM.NetID));
+    memcpy(rtcRAM.Address_Tx, lora.Address_Tx, sizeof(rtcRAM.Address_Tx));
+    memcpy(rtcRAM.NwkSKey, lora.NwkSKey, sizeof(rtcRAM.NwkSKey));
+    memcpy(rtcRAM.AppSKey, lora.AppSKey, sizeof(rtcRAM.AppSKey));
+    memcpy(&rtcRAM.Frame_Counter_Tx, &lora.Frame_Counter_Tx, sizeof(rtcRAM.Frame_Counter_Tx));
+    memcpy(&rtcRAM.LoRa_Settings, &lora.LoRa_Settings, sizeof(rtcRAM.LoRa_Settings));
+    memcpy(&rtcRAM.counter, &counter, sizeof(rtcRAM.counter));
+#if defined(ESP8266)
+    ESP.rtcUserMemoryWrite(32, (uint32_t *)&rtcRAM, sizeof(rtcRAM));
+#endif
+}
+
+void loadVariableRTC()
+{
+#if defined(ESP8266)
+    ESP.rtcUserMemoryRead(32, (uint32_t *)&rtcRAM, sizeof(rtcRAM));
+#endif
+    memcpy(lora.DevEUI, rtcRAM.DevEUI, sizeof(rtcRAM.DevEUI));
+    memcpy(lora.AppEUI, rtcRAM.AppEUI, sizeof(rtcRAM.AppEUI));
+    memcpy(lora.AppKey, rtcRAM.AppKey, sizeof(rtcRAM.AppKey));
+    memcpy(lora.DevNonce, rtcRAM.DevNonce, sizeof(rtcRAM.DevNonce));
+    memcpy(lora.AppNonce, rtcRAM.AppNonce, sizeof(rtcRAM.AppNonce));
+    memcpy(lora.NetID, rtcRAM.NetID, sizeof(rtcRAM.NetID));
+    memcpy(lora.Address_Tx, rtcRAM.Address_Tx, sizeof(rtcRAM.Address_Tx));
+    memcpy(lora.NwkSKey, rtcRAM.NwkSKey, sizeof(rtcRAM.NwkSKey));
+    memcpy(lora.AppSKey, rtcRAM.AppSKey, sizeof(rtcRAM.AppSKey));
+    memcpy(&lora.Frame_Counter_Tx, &rtcRAM.Frame_Counter_Tx, sizeof(rtcRAM.Frame_Counter_Tx));
+    memcpy(&lora.LoRa_Settings, &rtcRAM.LoRa_Settings, sizeof(rtcRAM.LoRa_Settings));
+    memcpy(&counter, &rtcRAM.counter, sizeof(rtcRAM.counter));
+}
+
+#if defined(ESP8266)
+uint32_t magicBytes; // if previous data save on rtc, this equal 'magi' (183510009)
+void loadMagicByte()
+{
+    ESP.rtcUserMemoryRead(127, &magicBytes, sizeof(magicBytes));
+}
+
+void saveMagicByte()
+{
+    magicBytes = 183510009;
+    ESP.rtcUserMemoryWrite(127, &magicBytes, 4);
+}
+#endif
+
+void setup()
+{
+    // Setup loraid access
+    Serial.begin(9600);
+    while (!Serial)
+        ;
+    if (!lora.init())
+    {
+        Serial.println("RFM95 not detected");
+        delay(5000);
+        deepsleep(10000000);
+    }
+
+    // Join procedure
+    bool isJoined = true;
+#if defined(ESP8266)
+    loadMagicByte();
+    if (magicBytes != 183510009)
+#else
+    if (rtcRAM.counter == 0)
+#endif
+    {
+        Serial.println("Cold boot Join procedure needs to be performed");
+        isJoined = false;
+    }
+
+    if (!isJoined)
+    {
+        // Set LoRaWAN Class change CLASS_A or CLASS_C
+        lora.setDeviceClass(CLASS_A);
+        // Set Data Rate
+        lora.setDataRate(SF9BW125);
+        // set channel to random
+        lora.setChannel(MULTI);
+
+        // Put OTAA Key and DevAddress here
+        lora.setDevEUI(devEui);
+        lora.setAppEUI(appEui);
+        lora.setAppKey(appKey);
+        while (!isJoined)
+        {
+            Serial.println("Joining...");
+            isJoined = lora.join();
+
+            // wait for 10s to try again if not join
+            if (!isJoined)
+                delay(10000);
+        }
+        Serial.println("Joined to network!\nWe now save LoRaWAN information");
+        delay(100); // Necessary for ESP32 in order to properly save data on RTC ram
+        saveVariableRTC();
+#if defined(ESP8266)
+        saveMagicByte();
+#endif
+    }
+    else
+    {
+        Serial.println("Previously joined network, we applied the save parameters");
+        loadVariableRTC();
+    }
+
+    // Send a upling
+    sprintf(myStr, "Counter-%d", counter);
+    Serial.print("Sending: ");
+    Serial.println(myStr);
+    lora.sendUplink(myStr, strlen(myStr), 0, 1);
+    counter++;
+
+    // cycle over send and receive data with LoRa update
+    lora.update();
+    recvStatus = lora.readData(outStr);
+    if (recvStatus)
+    {
+        Serial.println(outStr);
+    }
+    delay(100); // Necessary for ESP32 in order to properly save data on RTC ram
+    // Save pertinent information on RTC ram
+    saveVariableRTC();
+
+    // Deep sleep for 10 s
+    deepsleep(10000000);
+}
+
+void loop()
+{
+    // We never get here
+    Serial.print("Oups, you use this example without an ESP device");
+    delay(10000);
+}