A GattClient example based on ST BlueNRG driving an LED service exported by a BLE_LED peripheral. Shows scanning, connections, service-discovery, and reads/writes.

Dependencies:   BLE_API X_NUCLEO_IDB0XA1 mbed

Revision:
2:c944cfe08e79
Parent:
1:e0f4bcce540c
Child:
3:b2bf47485f85
--- a/main.cpp	Thu Jan 14 10:58:48 2016 +0000
+++ b/main.cpp	Fri Feb 19 15:32:04 2016 +0000
@@ -1,3 +1,4 @@
+#if 0
 /* mbed Microcontroller Library
  * Copyright (c) 2006-2013 ARM Limited
  *
@@ -176,3 +177,287 @@
     BLE::Instance().init(bleInitComplete);
 }
 
+#endif
+
+
+
+
+
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2015 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "mbed.h"
+#include "ble/Gap.h"
+#include "ble/BLE.h"
+#include "ble/DiscoveredCharacteristic.h"
+#include "ble/DiscoveredService.h"
+#include "ble/GapAdvertisingParams.h"
+
+
+#define PRINTF(...) printf(__VA_ARGS__)
+
+BLE  ble;
+DigitalOut led1(LED1);
+
+
+bool _connected = false;
+
+DiscoveredCharacteristic hrmCharacteristic;
+static volatile bool  triggerHrmCharacteristic = false;
+//PROTOTYPES
+void PrintScanResult(const Gap::AdvertisementCallbackParams_t *params);
+void periodicCallback(void);
+void connectToDevice(const Gap::Address_t peerAddr);
+
+void serviceDiscoveryCallback(const DiscoveredService *service); 
+void characteristicDiscoveryCallback(const DiscoveredCharacteristic *characteristicP); 
+void discoveryTerminationCallback(Gap::Handle_t connectionHandle);
+
+
+void disconnectionCallback(const Gap::DisconnectionCallbackParams_t *params) {
+    _connected = false;
+    PRINTF("disconnected\r\n");
+}
+
+void periodicCallback(void)
+{
+    led1 = !led1; /* Do blinky on LED1 while we're waiting for BLE events */
+    /* Note that the periodicCallback() executes in interrupt context, so it is safer to do
+     * heavy-weight sensor polling from the main thread. */
+    triggerHrmCharacteristic = true;
+}
+
+void PrintScanResult(const Gap::AdvertisementCallbackParams_t *params)
+{
+     for(int8_t i = 5; i>=0; i--)
+    {
+       PRINTF("%02x",params->peerAddr[i] );
+       if(i != 0)PRINTF("-");
+    }
+    PRINTF("\r\n");
+    
+    PRINTF("RSSI: %d\r\n",params->rssi );
+    
+    if(params->isScanResponse){
+        PRINTF("isScanResponse=true\r\n");
+    } else {
+        PRINTF("isScanResponse=false\r\n");
+    }
+   
+    switch(params->type)
+    {
+     case GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED:
+                                        PRINTF("ADV_CONNECTABLE_UNDIRECTED\r\n");
+                                        break;
+     case GapAdvertisingParams::ADV_CONNECTABLE_DIRECTED:
+                                        PRINTF("ADV_CONNECTABLE_DIRECTED\r\n");
+                                        break;
+     case GapAdvertisingParams::ADV_SCANNABLE_UNDIRECTED:
+                                        PRINTF("ADV_SCANNABLE_UNDIRECTED\r\n");
+                                        break;
+     case GapAdvertisingParams::ADV_NON_CONNECTABLE_UNDIRECTED:
+                                        PRINTF("ADV_NON_CONNECTABLE_UNDIRECTED\r\n");
+                                        break;  
+         
+    }
+    
+    PRINTF("advertisingDataLen: %d\r\n",params->advertisingDataLen );
+    
+    PRINTF("advertisingData: "); 
+    for(int i=0; i < params->advertisingDataLen; i++)
+    {
+        PRINTF("%02x",params->advertisingData[i]);
+        if(i != params->advertisingDataLen - 1)PRINTF("-");
+    }
+    PRINTF("\r\n");
+}
+
+
+void scanResultReceived(const Gap::AdvertisementCallbackParams_t *params)
+{
+    PRINTF("\r\nscanResultReceived\r\n");
+    
+    //print advertsing values
+   PrintScanResult(params);
+   
+   PRINTF("scan result ... try connect\r\n");
+   connectToDevice(params->peerAddr);
+}
+
+void connectToDevice(const Gap::Address_t peerAddr)
+{
+   ble_error_t  ret = ble.gap().connect(peerAddr, Gap::ADDR_TYPE_PUBLIC, NULL, NULL);
+   
+   if(ret == BLE_ERROR_NONE) { 
+           PRINTF("SUCCESS: connect\r\n");
+          } else {
+                 PRINTF("ERROR : connect\r\n");
+                 }
+}
+
+void serviceDiscoveryCallback(const DiscoveredService *service) { 
+    PRINTF("Service discovery callback\r\n");
+    
+    if (service->getUUID().shortOrLong() == UUID::UUID_TYPE_SHORT) {
+        PRINTF("S UUID-%x attrs[%u %u]\r\n", service->getUUID().getShortUUID(), service->getStartHandle(), service->getEndHandle());
+    } else {
+        printf("S UUID-");
+        const uint8_t *longUUIDBytes = service->getUUID().getBaseUUID();
+        for (unsigned i = 0; i < UUID::LENGTH_OF_LONG_UUID; i++) {
+            printf("%02x", longUUIDBytes[i]);
+        }
+        PRINTF(" attrs[%u %u]\r\n", service->getStartHandle(), service->getEndHandle());
+    }
+}
+ 
+void characteristicDiscoveryCallback(const DiscoveredCharacteristic *characteristicP) {
+    PRINTF("Characteristic discovery callback\r\n");
+    
+    PRINTF("  C UUID-%x valueAttr[%u] props[%x]\r\n", characteristicP->getUUID().getShortUUID(), characteristicP->getValueHandle(), (uint8_t)characteristicP->getProperties().broadcast());
+    //TODO: use hear rate characteristic
+    if (characteristicP->getUUID().getShortUUID() == 0x2A00) {
+        hrmCharacteristic = *characteristicP;
+        triggerHrmCharacteristic = true;
+       PRINTF("device name characteristic found\r\n");
+    }
+}
+ 
+void discoveryTerminationCallback(Gap::Handle_t connectionHandle) {
+    PRINTF("terminated SD for handle %u\r\n", connectionHandle);
+}
+
+void timeoutCallback(Gap::TimeoutSource_t param) {
+    
+    switch(param)
+    {
+        case Gap::TIMEOUT_SRC_ADVERTISING:
+                                    PRINTF("Timeout: Advertising\r\n");
+                                    break;
+        case Gap::TIMEOUT_SRC_SECURITY_REQUEST:
+                                    PRINTF("Timeout: Security access\r\n");
+                                    break;
+        case Gap::TIMEOUT_SRC_SCAN:
+                                    PRINTF("Timeout: Scan\r\n");
+                                    break;
+        case Gap::TIMEOUT_SRC_CONN:
+                                    PRINTF("Timeout: Conn\r\n");
+                                    break;
+    }
+}
+ 
+void connectionCallback(const Gap::ConnectionCallbackParams_t *params) {
+    if (params->role == Gap::CENTRAL) {
+        PRINTF("Launch service discovery\r\n");
+        //TODO: use heart rate service
+        ble.gattClient().onServiceDiscoveryTermination(discoveryTerminationCallback);
+        ble.gattClient().launchServiceDiscovery(params->handle, serviceDiscoveryCallback, characteristicDiscoveryCallback, 0x1800, 0x2A00);
+        _connected = true;
+     //   ble.gattClient().launchServiceDiscovery(params->handle, serviceDiscoveryCallback, characteristicDiscoveryCallback, GattService::UUID_HEART_RATE_SERVICE, GattCharacteristic::UUID_HEART_RATE_MEASUREMENT_CHAR); //BLE_UUID_UNKNOWN
+    }
+    else {
+        PRINTF("No central role\r\n");
+    }
+}
+
+
+void readCallback(const GattReadCallbackParams *response)
+{
+    PRINTF("readCallback\r\n");
+    
+    if (response->handle == hrmCharacteristic.getValueHandle()) {
+            PRINTF("readCallback: handle %u, offset %u, len %u\r\n", response->handle, response->offset, response->len);
+            for (unsigned index = 0; index < response->len; index++) {
+                PRINTF("%c[%02x]", response->data[index], response->data[index]);
+            }
+            PRINTF("\r\n");
+        }
+}
+
+/** 
+ * This function is called when the ble initialization process has failled 
+ */ 
+void onBleInitError(BLE &ble, ble_error_t error) 
+{ 
+    PRINTF("BLE init error"); 
+}
+
+/** 
+ * Callback triggered when the ble initialization process has finished 
+ */ 
+void bleInitComplete(BLE::InitializationCompleteCallbackContext *params) 
+{
+    
+    PRINTF("init complete\r\n");
+    
+    BLE&        ble   = params->ble;
+    ble_error_t error = params->error;
+ 
+    if (error != BLE_ERROR_NONE) {
+        /* In case of error, forward the error handling to onBleInitError */
+        PRINTF("Error init\r\n");
+        onBleInitError(ble, error);
+        return;
+    }
+ 
+    /* Ensure that it is the default instance of BLE */
+    if(ble.getInstanceID() != BLE::DEFAULT_INSTANCE) {
+        PRINTF("Error default instance\r\n");
+        return;
+    }
+ 
+   ble.onTimeout(timeoutCallback);
+   ble.onConnection(connectionCallback);
+   ble.onDisconnection(disconnectionCallback);
+   ble.gattClient().onDataRead(readCallback);
+   
+    ble.gap().setScanParams(300, 300);
+    ble.gap().startScan(scanResultReceived);
+    PRINTF("scan started...\r\n");
+
+    
+    // infinite loop
+    while (1) {
+        // check for trigger from periodicCallback()
+         if (triggerHrmCharacteristic && !ble.gattClient().isServiceDiscoveryActive() && _connected) {
+            
+            triggerHrmCharacteristic = false;
+            PRINTF("START READ\r\n");
+            hrmCharacteristic.read(); 
+            
+        } else {
+            ble.waitForEvent(); // low power wait for event
+        }
+    }
+  
+    
+   
+    
+}
+
+int main(void)
+{
+    PRINTF("started...\r\n");
+    
+    led1 = 1;
+    Ticker ticker;
+    ticker.attach(periodicCallback, 1); // blink LED every second
+    
+    _connected = false;
+    
+    PRINTF("start init...\r\n");
+    
+    ble.init(bleInitComplete);  
+}
\ No newline at end of file