Help - Subscribe to a Characteristic with indicate properties

[mathbozzi]

I'm trying to read from my Blood Pressure monitor. The service is 1810 and the characteristic is 2a35, but the buffer is empty. The properties is: [ 'indicate' ].

My code:

const noble = require('@abandonware/noble')

 noble.on('stateChange', async (state) => {
    if (state === 'poweredOn') {
        await noble.startScanningAsync([], false);
    }else {
        noble.stopScanningAsync();
    }
 });


noble.on('discover', async (peripheral) => {
    console.log(peripheral.id)
    if (peripheral.id === "ec21e54394ca") peripheral.connectAsync(() => {


        peripheral.discoverServices(['1810'],(e, services) => {
            const bp = services[0];
            console.log({ bp })
            bp.discoverCharacteristics(['2a35'], (e, characteristics) => {   
                const chara = characteristics[0]
                // chara.notify(true,async function(error){});
                chara.subscribeAsync();
                // chara.subscribe();
                console.log("here");
                console.log(chara);

                // chara.once('read', (data) => {
                //     console.log(data);
                // })
                chara.once('data', async function(data,isNotification){
                    console.log('hello',data, isNotification);
                })

                chara.readAsync(async (error,data)=>{
                    console.log(data);
                })

            })
        })

    })
})

---

out:

ec21e54394ca    
{
  bp: Service {
    _noble: Noble {
      initialized: true,
      address: '00:1a:7d:da:71:13',
      _state: 'poweredOn',
      _bindings: [NobleBindings],
      _peripherals: [Object],
      _services: [Object],
      _characteristics: [Object],
      _descriptors: [Object],
      _discoveredPeripheralUUids: [Array],
      _events: [Object: null prototype],
      _eventsCount: 4,
      _allowDuplicates: false
    },
    _peripheralId: 'ec21e54394ca',
    uuid: '1810',
    name: 'Blood Pressure',
    type: 'org.bluetooth.service.blood_pressuer',
    includedServiceUuids: null,
    characteristics: null
  }
}
here
Characteristic {
  _noble: Noble {
    initialized: true,
    address: '00:1a:7d:da:71:13',
    _state: 'poweredOn',
    _bindings: NobleBindings {
      _state: 'poweredOn',
      _addresses: [Object],
      _addresseTypes: [Object],
      _connectable: [Object],
      _pendingConnectionUuid: null,
      _connectionQueue: [],
      _handles: [Object],
      _gatts: [Object],
      _aclStreams: [Object],
      _signalings: [Object],
      _hci: [Hci],
      _gap: [Gap],
      _events: [Object: null prototype],
      _eventsCount: 24,
      onSigIntBinded: [Function: bound ],
      _scanServiceUuids: []
    },
    _peripherals: { ec21e54394ca: [Peripheral] },
    _services: { ec21e54394ca: [Object] },
    _characteristics: { ec21e54394ca: [Object] },
    _descriptors: { ec21e54394ca: [Object] },
    _discoveredPeripheralUUids: [ 'ec21e54394ca' ],
    _events: [Object: null prototype] {
      warning: [Function (anonymous)],
      newListener: [Function (anonymous)],
      stateChange: [AsyncFunction (anonymous)],
      discover: [AsyncFunction (anonymous)]
    },
    _eventsCount: 4,
    _allowDuplicates: false
  },
  _peripheralId: 'ec21e54394ca',
  _serviceUuid: '1810',
  uuid: '2a35',
  name: 'Blood Pressure Measurement',
  type: 'org.bluetooth.characteristic.blood_pressure_measurement',
  properties: [ 'indicate' ],                 /////////// INDICATE
  descriptors: null,
  _events: [Object: null prototype] {
    notify: [Function: bound onceWrapper] { listener: [Function (anonymous)] }
  },
  _eventsCount: 1
}
hello <Buffer > false                       /////////////BUFFER EMPTY
<Buffer >                                        //////////// BUFFER EMPTY

---

Buffer is empty, means that i'm not subscribed? ..

[rzr]

Please also check with:

https://www.npmjs.com/package/@abandonware/noble/v/1.9.2-13

Relate-to: #926