Datasheet

Advertising and Scanner

It is possible to start both the scanner and advertising at the same time so that we can discover and be discovered by

other BLE devices. For the scanner, we use a filter that only fires the callback if a specific UUID is found in the

advertising data of the peer device:

Full Sample Code

The full sample code for this example can be seen below, but this maybe be out of sync with the latest code available

on Github. Please consult the Github code (https://adafru.it/BiS) if you have any problems with the code below.

// Callbacks for Central

Bluefruit.Central.setConnectCallback(cent_connect_callback);

Bluefruit.Central.setDisconnectCallback(cent_disconnect_callback);

/* Start Central Scanning

* - Enable auto scan if disconnected

* - Interval = 100 ms, window = 80 ms

* - Filter only accept bleuart service

* - 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.filterUuid(bleuart.uuid);

Bluefruit.Scanner.useActiveScan(false);

Bluefruit.Scanner.start(0); // 0 = Don't stop scanning after n seconds

// Advertising packet

Bluefruit.Advertising.addFlags(BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE);

Bluefruit.Advertising.addTxPower();

// Include bleuart 128-bit uuid

Bluefruit.Advertising.addService(bleuart);

// Secondary Scan Response packet (optional)

// Since there is no room for 'Name' in Advertising packet

Bluefruit.ScanResponse.addName();

/* Start Advertising

* - Enable auto advertising if disconnected

* - Interval: fast mode = 20 ms, slow mode = 152.5 ms

* - Timeout for fast mode is 30 seconds

* - Start(timeout) with timeout = 0 will advertise forever (until connected)

* For recommended advertising interval

* https://developer.apple.com/library/content/qa/qa1931/_index.html

Bluefruit.Advertising.restartOnDisconnect(true);

Bluefruit.Advertising.setInterval(32, 244); // in unit of 0.625 ms

Bluefruit.Advertising.setFastTimeout(30); // number of seconds in fast mode

Bluefruit.Advertising.start(0); // 0 = Don't stop advertising after n seconds

#include <bluefruit.h>