How to use on_notification fuction to get notification

[scps990707]

I am a python beginner, I read a lot of related questions, but they all ask us to look heart_rate_collector.py , but heart_rate_collector.py did't not have any example, i really don't understand how to used it.

def on_notification(self, ble_adapter, conn_handle, uuid, data):

data should be the thing i want to get,is that right?

 

[scps990707]

    def __init__(self, adapter):
        super(NusCollector, self).__init__()
        self.first = 1
        self.adapter = adapter
        self.conn_q = Queue()
        self.adapter.observer_register(self)
        self.adapter.driver.observer_register(self)
        self.adapter.default_mtu = 247
        self.nus_base = BLEUUIDBase([
            0x00, 0x00, 0xff, 0xf0, 0x00 ,0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0x80, 0x5f, 0x9b, 0x34, 0xfb
        ])
        self.nus_tx = BLEUUID(0xfff6, self.nus_base)

self.nus_tx is the UUID of 0XFFF6 which is the notify one

[Einar Thorsrud]

Is the UUID Base right? In the screenshot it looks like you are using only 16 bit UUIDs, but here you are adding a base (which is probably what you should do as this is a custom service). But in any case, in order to work, this needs to match.

[scps990707]

self.nus_base = BLEUUIDBase([

0x00, 0x00, 0xff, 0xf0, 0x00 ,0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0x80, 0x5f, 0x9b, 0x34, 0xfb

])

self.nus_tx = BLEUUID(0xfff6, self.nus_base)

I think BLEUUID is to mix "0xfff6" and "self.nus_base",so self.nus_tx become[0x00, 0x00, 0xff, 0xf6, 0x00 ,0x00, 0x10, 0x00, 0x80, 0x00, 0x00, 0x80, 0x5f, 0x9b, 0x34, 0xfb]?

I also got the return form enable_notification() ,and get "None" so i think maybe my UUID is wrong

this is the UUID I want to receive data

[scps990707]

Hello is there anything I can do for it?

[Einar Thorsrud]

I don't immediately see an issue here. I suggest you take a look at this post, which includes a working script that use NUS, and enables notifications (obviously you need to change the UUID and UUID base for your custom service).