familiarization demo code

part 2

Author: fabiankuffer

main/CMakeLists.txt

@@ -1,5 +1,7 @@
 set(srcs "main.cpp"
-         "functions.cpp")
+         "common.cpp"
+         "gap.cpp"
+         "gatt.cpp")
 
 idf_component_register(SRCS "${srcs}"
                     INCLUDE_DIRS ".")

main/functions.cpp main/common.cppmain/functions.cpp renamed to main/common.cpp

@@ -20,6 +20,6 @@ static void bleprhp_on_sync(void){
     rc = ble_hs_id_infer_auto(0, &bleprhp_addr_type);
     assert(rc == 0);
 
-    //TODO
-    //bleprhp_advertise();
+    /*start advertising, when controller and host are in sync*/
+    bleprhp_advertise();
 }

main/gap.cpp

@@ -0,0 +1,87 @@
+#include "main.hpp"
+
+static void bleprhp_advertise(void){
+    struct ble_gap_adv_params adv_params;
+    struct ble_hs_adv_fields fields;
+    int rc;
+
+    /*
+    set the advertisement data included in our advertisements:
+    -flags (indicates advertisement type and other gernal info)
+    -advertising tx power
+    -device name
+    */
+    memset(&fields, 0, sizeof(fields));
+
+    /*advertise two flags:
+    -discoverability in forhtcoming advertisement (general)
+    -ble-only (br/edr unsupported)
+    */
+    fields.flags = BLE_HS_ADV_F_DISC_GEN | BLE_HS_ADV_F_BREDR_UNSUP;
+
+    /*inidcate that the tx power level field should be included; have the stack fill this value automatically. This is done ba assigning the special value BLE_HS_ADV_TX_PWR_LVL_AUTO.
+    */
+    fields.tx_pwr_lvl_is_present = 1;
+    fields.tx_pwr_lvl = BLE_HS_ADV_TX_PWR_LVL_AUTO;
+
+    fields.name = (uint8_t *)CONFIG_BT_NIMBLE_SVC_GAP_DEVICE_NAME;
+    fields.name_len = strlen(CONFIG_BT_NIMBLE_SVC_GAP_DEVICE_NAME);
+    fields.name_is_complete = 1;
+
+    rc = ble_gap_adv_set_fields(&fields);
+    if (rc != 0){
+        ESP_LOGE(tag, "error setting advertisement data; rc=%d\n",rc);
+    }
+
+    /*Begin advertising*/
+    memset(&adv_params, 0, sizeof(adv_params));
+    //TODO
+    adv_params.conn_mode = BLE_GAP_CONN_MODE_UND;
+    adv_params.disc_mode = BLE_GAP_DISC_MODE_GEN;
+    rc = ble_gap_adv_start(bleprhp_addr_type, NULL, BLE_HS_FOREVER, &adv_params, bleprhp_gap_event, NULL);
+    if (rc != 0){
+        ESP_LOGE(tag, "error enabling advertisement; rc=%d\n",rc);
+    }
+}
+
+static int bleprhp_gap_event(struct ble_gap_event *event, void *arg){
+    switch(event->type){
+        case BLE_GAP_EVENT_CONNECT:
+            //A new connection was establied or a connection attempt failed
+            ESP_LOGI(tag, "connection %s; status=%d\n",event->connect.status == 0 ? "established" : "failed",event->connect.status);
+
+            if(event->connect.status != 0){
+                //Conection failed; resume advertising
+                bleprhp_advertise();
+            }
+            conn_handle = event->connect.conn_handle;
+            break;
+        case BLE_GAP_EVENT_DISCONNECT:
+            ESP_LOGI(tag, "disconnect; reason%d\n", event->disconnect.reason);
+            //connection terminated; resume advertising
+            bleprhp_advertise();
+            break;
+        case BLE_GAP_EVENT_ADV_COMPLETE:
+            //TODO
+            ESP_LOGI(tag, "adv complete\n");
+            bleprhp_advertise();
+            break;
+        case BLE_GAP_EVENT_SUBSCRIBE:
+            //TODO
+            /*ESP_LOGI(tag, "subscribe event; cur_notify=%d\n value handle; val_handle=%d\n", event->subscribe.cur_notify, hrs_hrm_handle);
+            if(event->subscribe.attr_handle == hrs_hrm_handle){
+                notify_state = event->subscribe.cur_notify;
+                blehr_tx_hrate_reset();
+            } else if (event->subscribe.attr_handle != hrs_hrm_handle){
+                notify_state = event->subscribe.cur_notify;
+                blehr_tx_hrate_stop();
+            }*/
+            ESP_LOGI(tag, "conn_handle from subscribe=%d", conn_handle);
+            break;
+        case BLE_GAP_EVENT_MTU:
+            ESP_LOGI(tag, "mtu update event; conn_handle=%d mtu=%d\n", event->mtu.conn_handle, event->mtu.value);
+            break;
+    }
+
+    return 0;
+}

main/gatt.cpp

@@ -0,0 +1,12 @@
+#include "main.hpp"
+
+int gatt_svr_init(void){
+    int rc;
+
+    ble_svc_gap_init();
+    ble_svc_gatt_init();
+
+    //TODO
+    rc = ble_gatts_count_cfg(gatt_svr_srvcs);
+
+}

main/main.cpp

@@ -7,6 +7,7 @@ extern "C" void app_main(void)
     int rc;
 
     /*Initialize NVS - it is used to store PHY calibration data*/
+    //NVS = Non-volatile storage library is designed to store key-balue pairs in flash
     //Ablauf ist in esp idf beschrieben
     //docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/bluetooth/nimble/index.html
     esp_err_t ret = nvs_flash_init();
@@ -37,7 +38,7 @@ extern "C" void app_main(void)
     ble_hs_cfg.sm_their_key_dist = 1;
 
     //TODO
-    //rc = gatt_svr_init();
+    rc = gatt_svr_init();
     assert(rc == 0);
 
     /*Set the default device name. */

main/main.hpp

@@ -14,19 +14,29 @@
 #include "nimble/nimble_port_freertos.h"
 #include "host/ble_hs.h"
 #include "services/gap/ble_svc_gap.h"
+#include "services/gatt/ble_svc_gatt.h"
 
 extern "C" {
 
 static const char *tag = "SimLinkModule_BLE";
 
 static uint8_t bleprhp_addr_type;
 
+//eindeutiges handle was bei einem verbindungsaufbau einer verbindung zugeordnet wird
+static uint16_t conn_handle;
+
 //start nimble in a task
 void bleprph_host_task(void *param);
 //This callback is executed when the host resets itself and the controller
 static void bleprhp_on_reset(int reason);
 //This callback is executed when the host and controller become synced. This happens at startup and after a reset
 static void bleprhp_on_sync(void);
+//enables advertising with parameters: general discoverable mode and unidrect connectable mode
+static void bleprhp_advertise(void);
+//The callback to associate with this advertising procedure. If advertising ends, the event is reported through this callback. If advertising results in a connection, the connection inherits this callback as its event-reporting mechanism.
+static int bleprhp_gap_event(struct ble_gap_event *event, void *arg);
+//init gatt server
+int gatt_svr_init(void);
 }
 
 #endif