Receive downlink messages

component.mk

@@ -1,4 +1,2 @@
-CFLAGS += -Wno-error=maybe-uninitialized -Wno-error=unused-value
-
 COMPONENT_ADD_INCLUDEDIRS := include
 COMPONENT_SRCDIRS := src

examples/send_recv/Makefile

@@ -0,0 +1,3 @@
+PROJECT_NAME := hello_world
+
+include $(IDF_PATH)/make/project.mk

examples/send_recv/components/ttn-esp32

@@ -0,0 +1 @@
+../../../../ttn-esp32/

examples/send_recv/main/main.cpp

@@ -0,0 +1,87 @@
+/*******************************************************************************
+ * Copyright (c) 2018 Manuel Bleichenbacher
+ * 
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Sample program showing how to send a test message every 30 second.
+ *******************************************************************************/
+
+#include "freertos/FreeRTOS.h"
+#include "esp_event.h"
+
+#include "TheThingsNetwork.h"
+
+// NOTE:
+// The LoRaWAN frequency and the radio chip must be configured by running 'make menuconfig'.
+// Go to Components / The Things Network, select the appropriate values and save.
+
+// Copy the below hex string from the "Device EUI" field
+// on your device's overview page in the TTN console.
+const char *devEui = "????????????????";;
+
+// Copy the below two lines from bottom of the same page
+const char *appEui = "????????????????";
+const char *appKey = "????????????????????????????????";
+
+
+static TheThingsNetwork ttn;
+
+const unsigned TX_INTERVAL = 30;
+static uint8_t msgData[] = "Hello, world";
+
+
+void sendMessages(void* pvParameter)
+{
+    while (1) {
+        printf("Sending message...\n");
+        ttn_response_t res = ttn.sendBytes(msgData, sizeof(msgData) - 1);
+        if (res == TTN_SUCCESSFUL_TRANSMISSION)
+            printf("Message sent.\n");
+        else if (res == TTN_SUCCESSFUL_RECEIVE)
+            printf("Message sent and message received\n");
+        else
+            printf("Message transmission failed.\n");
+
+        vTaskDelay(TX_INTERVAL * 1000 / portTICK_PERIOD_MS);
+    }
+}
+
+void messageReceived(const uint8_t* message, size_t length, port_t port)
+{
+    printf("Message of %d bytes received on port %d:", length, port);
+    for (int i = 0; i < length; i++)
+        printf(" %02x", message[i]);
+    printf("\n");
+}
+
+extern "C" void app_main(void)
+{
+    gpio_install_isr_service(ESP_INTR_FLAG_IRAM);
+
+    // Initialize SPI bus
+    spi_bus_config_t spi_bus_config;
+    spi_bus_config.miso_io_num = 19;
+    spi_bus_config.mosi_io_num = 27;
+    spi_bus_config.sclk_io_num = 5;
+    spi_bus_config.quadwp_io_num = -1;
+    spi_bus_config.quadhd_io_num = -1;
+    spi_bus_config.max_transfer_sz = 0;
+
+    esp_err_t ret = spi_bus_initialize(HSPI_HOST, &spi_bus_config, 1);
+    assert(ret == ESP_OK);
+
+    ttn.configurePins(HSPI_HOST, 18, TTN_NOT_CONNECTED, 14, 26, 33);
+
+    ttn.provision(devEui, appEui, appKey);
+
+    ttn.onMessage(messageReceived);
+
+    printf("Joining...\n");
+    ttn.join();
+    printf("Joined.\n");
+
+    xTaskCreate(sendMessages, "send_messages", 1024 * 4, (void* )0, 3, NULL);
+}

include/TheThingsNetwork.h

@@ -15,9 +15,6 @@
 #include <stdint.h>
 #include "driver/spi_master.h"
 
-#define TTN_DEFAULT_SF 7
-#define TTN_DEFAULT_FSB 2
-
 /**
  * @brief Constant for indicating that a pin is not connected
  */
@@ -37,6 +34,14 @@ enum ttn_response_t
   TTN_SUCCESSFUL_RECEIVE = 2
 };
 
+/**
+ * @brief Callback for recieved messages
+ * 
+ * @param payload  pointer to the received bytes
+ * @param length   number of received bytes
+ * @param port     port the message was received on
+ */
+typedef void (*message_cb_t)(const uint8_t* payload, size_t length, port_t port);
 
 /**
  * @brief TTN device
@@ -114,11 +119,35 @@ public:
      */
     bool join();
 
+    /**
+     * @brief Send a message
+     * 
+     * @param payload  bytes to be sent
+     * @param length   number of bytes to be sent
+     * @param port     port (default to 1)
+     * @param confirm  flag indicating if a confirmation should be requested. Default to 'false'
+     * @return TTTN_SUCCESSFUL_TRANSMISSION    Successful transmission
+     * @return TTTN_SUCCESSFUL_RECEIVE         Successful transmission and a message has been received
+     * @return TTN_ERROR_SEND_COMMAND_FAILED   Transmission failed
+     * @return TTTN_ERROR_UNEXPECTED_RESPONSE  Unexpected response
+     */
     ttn_response_t sendBytes(const uint8_t *payload, size_t length, port_t port = 1, bool confirm = false);
 
+    /**
+     * @brief Set the function to be called when a message is received
+     * 
+     * When a message is received, the specified function is called. The
+     * message, its length and the port is was received on are provided as
+     * parameters. The values are only valid during the duration of the
+     * callback. So they must be immediately processed or copied.
+     * 
+     * @param callback  the callback function
+     */
+    void onMessage(message_cb_t callback);
+
+
 private:
-    uint8_t spreadingFactor = TTN_DEFAULT_SF;
-    uint8_t frequencySubband = TTN_DEFAULT_FSB;
+    message_cb_t messageCallback;
 
     bool decodeKeys(const char *devEui, const char *appEui, const char *appKey);
 };

src/TheThingsNetwork.cpp

@@ -112,12 +112,16 @@ bool TheThingsNetwork::join(const char *devEui, const char *appEui, const char *
 
 bool TheThingsNetwork::join()
 {
+    int result = 0;
+    // empty queue
+    while (xQueueReceive(result_queue, &result, 0) == pdTRUE)
+        ;
+
     hal_enterCriticalSection();
     LMIC_startJoining();
     hal_wakeUp();
     hal_leaveCriticalSection();
 
-    int result = 0;
     while (true)
     {
         xQueueReceive(result_queue, &result, portMAX_DELAY);
@@ -130,6 +134,11 @@ bool TheThingsNetwork::join()
 
 ttn_response_t TheThingsNetwork::sendBytes(const uint8_t *payload, size_t length, port_t port, bool confirm)
 {
+    int result = 0;
+    // empty queue
+    while (xQueueReceive(result_queue, &result, 0) == pdTRUE)
+        ;
+
     hal_enterCriticalSection();
     if (LMIC.opmode & OP_TXRXPEND)
     {
@@ -141,9 +150,28 @@ ttn_response_t TheThingsNetwork::sendBytes(const uint8_t *payload, size_t length
     hal_wakeUp();
     hal_leaveCriticalSection();
 
-    int result = 0;
     xQueueReceive(result_queue, &result, portMAX_DELAY);
-    return result == EV_TXCOMPLETE ? TTN_SUCCESSFUL_TRANSMISSION : TTN_ERROR_SEND_COMMAND_FAILED;
+
+    if (result == EV_TXCOMPLETE)
+    {
+        bool hasRecevied = (LMIC.txrxFlags & (TXRX_DNW1 | TXRX_DNW2)) != 0;
+        if (hasRecevied && messageCallback != NULL)
+        {
+            port_t port = 0;
+            if ((LMIC.txrxFlags & TXRX_PORT))
+                port = LMIC.frame[LMIC.dataBeg - 1];
+            messageCallback(LMIC.frame + LMIC.dataBeg, LMIC.dataLen, port);
+        }
+
+        return hasRecevied ? TTN_SUCCESSFUL_RECEIVE : TTN_SUCCESSFUL_TRANSMISSION;
+    }
+
+    return  TTN_ERROR_SEND_COMMAND_FAILED;
+}
+
+void TheThingsNetwork::onMessage(message_cb_t callback)
+{
+    messageCallback = callback;
 }
 
 
@@ -190,9 +218,7 @@ void onEvent (ev_t ev) {
 
     if (ev == EV_TXCOMPLETE) {
         if (LMIC.txrxFlags & TXRX_ACK)
-            ESP_LOGI(TAG, "Received ack\n");
-        if (LMIC.dataLen)
-            ESP_LOGI(TAG, "Received %d bytes of payload\n", LMIC.dataLen);
+            ESP_LOGI(TAG, "ACK received\n");
     }
 
     int result = ev;

src/radio.c

@@ -25,6 +25,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include "rom/ets_sys.h"
 #include "lmic.h"
 
 // ---------------------------------------- 
@@ -500,13 +501,14 @@ static void txlora () {
     // select LoRa modem (from sleep mode)
     //writeReg(RegOpMode, OPMODE_LORA);
     opmodeLora();
-    // can take a moment to change; so try five times
+    // can take a moment to change; so try ten times
     u1_t reg;
-    for (int i = 0; i < 5; i++)
+    for (int i = 0; i < 10; i++)
     {
         reg = readReg(RegOpMode);
         if ((reg & OPMODE_LORA) != 0)
             break;
+        ets_delay_us(100);
     }
     ASSERT((reg & OPMODE_LORA) != 0);