Getting Blood Pressure Measurement (Service: 1810)

[saenzramiro]

Hi everybody,

I'm trying to get the BPM values from "A&D" device (model UA-651BLE).

The service to get that data is 1810 and the characteristic is 2A35. I used the battery example as a base to get this values, but I don't know why is always failed (print "Read failed"). I tried to get this data in pair mode (holding the power button until shows "Pr" in the display) or immediately after getting my BPM.

My code (after scanning and connecting):

var onReadSuccess = function(data) {
    var a = new Uint8Array(data);
    console.log('onReadSuccess', data, a);
}

var onReadFail = function(error) {
    console.log('onReadFail', error);
}

ble.read('7C:66:9D:88:B2:B8', '1810', '2a35', onReadSuccess, onReadFail);

I saw other apps that they could get this data from my device, but I think they do it natively.

Can anyone helps me?

Thanks.

[tl8roy]

Try using the full UUID for the service and characteristic.

[saenzramiro]

Do you mean "0x1810" and "0x2a35"? Or like "00002A35-0000-1000-8000-00805f9b34fb"?

[tl8roy]

The long version.
Also try it with the nRF Master Control Panel https://play.google.com/store/apps/details?id=no.nordicsemi.android.mcp&hl=en

[don]

According to the specs, blood pressure only uses indicate you can't read it.

Indicate has not implemented in the plugin yet. If you add support for indicate this please submit a pull request.

As for the short vs long uuids, the plugin will translate 16-bit UUIDs into their 2a35 128-bit form internally for Android. You should use the short UUIDs.

[don]

@saenzramiro On iOS is looks like notifications and indications are handled the same from an API perspective so you should be able to use startNotification to receive a callback when 2a35 changes on 1810. Depending on the Android behavior, I'll probably add a startIndication() method to both iOS and Android in a future version of the plugin.

https://developer.apple.com/library/ios/documentation/CoreBluetooth/Reference/CBPeripheral_Class/#//apple_ref/occ/instm/CBPeripheral/setNotifyValue:forCharacteristic:

[don]

startNotification now supports notification and indication on both iOS and Android

var onData = function(buffer) {
    var data = new Uint16Array(buffer);
    console.log(data[0]);
}

ble.startNotification(deviceId, '1810', '2a35', onData, failure)

[daniperezluna]

@saenzramiro Could you send me your code?? I am triying to do something like this. Thanks.

[GeneLiulumira]

aaa

[ftaibi]

@don Hi there I have the same problem, I am using the startNotification method and I get this:

ERROR: Attempt to invoke virtual method 'java.util.List android.bluetooth.BluetoothGattService.getCharacteristics()' on a null object reference

I am using the service 1810 and the characteristic 2a35