adding central throuhgput example

Author: hathach

libraries/Bluefruit52Lib/examples/Central/central_throughput/central_throughput.ino

@@ -0,0 +1,158 @@
+/*********************************************************************
+ This is an example for our nRF52 based Bluefruit LE modules
+
+ Pick one up today in the adafruit shop!
+
+ Adafruit invests time and resources providing this open source code,
+ please support Adafruit and open-source hardware by purchasing
+ products from Adafruit!
+
+ MIT license, check LICENSE for more information
+ All text above, and the splash screen below must be included in
+ any redistribution
+*********************************************************************/
+
+/*
+ * This sketch demonstrate the central API(). A additional bluefruit
+ * that has bleuart as peripheral is required for the demo.
+ */
+#include <bluefruit.h>
+
+BLEClientUart clientUart; // bleuart client
+
+void setup()
+{
+  Serial.begin(115200);
+  while ( !Serial ) delay(10);   // for nrf52840 with native usb
+
+  Serial.println("Bluefruit52 Central BLEUART Example");
+  Serial.println("-----------------------------------\n");
+  
+  // Initialize Bluefruit with maximum connections as Peripheral = 0, Central = 1
+  // SRAM usage required by SoftDevice will increase dramatically with number of connections
+  Bluefruit.begin(0, 1);
+  
+  Bluefruit.setName("Bluefruit52 Central");
+
+  // Init BLE Central Uart Serivce
+  clientUart.begin();
+  clientUart.setRxCallback(bleuart_rx_callback);
+
+  // Increase Blink rate to different from PrPh advertising mode
+  Bluefruit.setConnLedInterval(250);
+
+  // Callbacks for Central
+  Bluefruit.Central.setConnectCallback(connect_callback);
+  Bluefruit.Central.setDisconnectCallback(disconnect_callback);
+
+  /* Start Central Scanning
+   * - Enable auto scan if disconnected
+   * - Interval = 100 ms, window = 80 ms
+   * - Don't use active scan
+   * - Start(timeout) with timeout = 0 will scan forever (until connected)
+   */
+  Bluefruit.Scanner.setRxCallback(scan_callback);
+  Bluefruit.Scanner.restartOnDisconnect(true);
+  Bluefruit.Scanner.setInterval(160, 80); // in unit of 0.625 ms
+  Bluefruit.Scanner.useActiveScan(false);
+  Bluefruit.Scanner.start(0);                   // // 0 = Don't stop scanning after n seconds
+}
+
+/**
+ * Callback invoked when scanner pick up an advertising data
+ * @param report Structural advertising data
+ */
+void scan_callback(ble_gap_evt_adv_report_t* report)
+{
+  // Check if advertising contain BleUart service
+  if ( Bluefruit.Scanner.checkReportForService(report, clientUart) )
+  {
+    Serial.print("BLE UART service detected. Connecting ... ");
+
+    // Connect to device with bleuart service in advertising
+    Bluefruit.Central.connect(report);
+  }else
+  {      
+    // For Softdevice v6: after received a report, scanner will be paused
+    // We need to call Scanner resume() to continue scanning
+    Bluefruit.Scanner.resume();
+  }
+}
+
+/**
+ * Callback invoked when an connection is established
+ * @param conn_handle
+ */
+void connect_callback(uint16_t conn_handle)
+{
+  Serial.println("Connected");
+
+  Serial.print("Discovering BLE Uart Service ... ");
+  if ( clientUart.discover(conn_handle) )
+  {
+    Serial.println("Found it");
+
+    Serial.println("Enable TXD's notify");
+    clientUart.enableTXD();
+
+    Serial.println("Ready to receive from peripheral");
+  }else
+  {
+    Serial.println("Found NONE");
+    
+    // disconnect since we couldn't find bleuart service
+    Bluefruit.disconnect(conn_handle);
+  }  
+}
+
+/**
+ * Callback invoked when a connection is dropped
+ * @param conn_handle
+ * @param reason is a BLE_HCI_STATUS_CODE which can be found in ble_hci.h
+ */
+void disconnect_callback(uint16_t conn_handle, uint8_t reason)
+{
+  (void) conn_handle;
+  (void) reason;
+  
+  Serial.println("Disconnected");
+}
+
+/**
+ * Callback invoked when uart received data
+ * @param uart_svc Reference object to the service where the data 
+ * arrived. In this example it is clientUart
+ */
+void bleuart_rx_callback(BLEClientUart& uart_svc)
+{
+  Serial.print("[RX]: ");
+  
+  while ( uart_svc.available() )
+  {
+    Serial.print( (char) uart_svc.read() );
+  }
+
+  Serial.println();
+}
+
+void loop()
+{
+  if ( Bluefruit.Central.connected() )
+  {
+    // Not discovered yet
+    if ( clientUart.discovered() )
+    {
+      // Discovered means in working state
+      // Get Serial input and send to Peripheral
+      if ( Serial.available() )
+      {
+        delay(2); // delay a bit for all characters to arrive
+        
+        char str[20+1] = { 0 };
+        Serial.readBytes(str, 20);
+        
+        clientUart.print( str );
+      }
+    }
+  }
+}