Why my gateway can only connect to the Xiaomi band 2,

[1114752670@qq.com]

rbattery = ble.sockreadhnd(sock,0x47) or '' 

I want to ask specifically how this function is implemented when extracting the data I want. For example (sock, 0x47) in why 0x47 must be this, what basis.

---

I want to figure out a function                x = ble. sockreadhnd (sock, 22) or''                         about extracting data from Bluetooth.

How do I get the two byte attribute handle。For example, I use an BLE Scanner APP，How do I get what the two byte attribute handle I want in this App。