Scan for nearby Bluetooth LE peripherals using HM-11 and Arduino. This works on any ble device that advertises itself: beacons, trackers, wearables.
The code puts the HM-11 into master mode, and then scans every minute for nearby devices. Software returns device name and id.
Connect the HM-11 pins to a 3.3v Arduino, or to a regular 5v Arduino through a logic level shifter.
_______
| | HM-11 --> Arduino
1 : : 16 9 3.3V
: : 12 GND
: : 4 (RX) 3 (TX)
8 :_______: 9 2 (TX) 2 (RX)
HM-11