RE: CCCD and Read properties

jerome.sc — Fri, 20 Jan 2023 11:30:40 GMT

Thanks for the clear answer!

RE: CCCD and Read properties

Hung Bui — Fri, 20 Jan 2023 11:21:53 GMT

Hi Jerome,

CCCD and read property is not directly related to each other.
CCCD is the control attribute that allow the server to send notification/indication of the value of the characteristic.
When the read property allow the client to read the value characteristic.

Even though the result of the two activity are the same, the value of the characteristic is delivered from the server to the client. But they are 2 different activities, one is that the server decides to send to the client the value (notification/indication). The other is that the client read the value from the server.
When you use notification, the server decide when to send the notification. When you use read, the client decide when to read the value. That's why you need to click on the read button on the phone to read the characteristic.

You don't have to have both CCCD and read properties but you can choose to have both if you want to support both, notification and read.