GATT Characteristic Read Timeout

RE: GATT Characteristic Read Timeout

Frederic — Thu, 27 Nov 2014 12:38:55 GMT

Ok, thank you.

RE: GATT Characteristic Read Timeout

Ulrich Myhre — Thu, 27 Nov 2014 12:28:29 GMT

It is defined as 30 seconds in the spec. See Vol 3 (Host) - Part F (ATT) - 3.3.3 (Transaction).

"A transaction not completed within 30 seconds shall time out. Such a transaction shall be considered to have failed and the local higher layers shall be informed of this failure. No more attribute protocol requests, commands, indications or notifications shall be sent to the target device on this ATT Bearer."

GATT is an extension built on top of ATT, so it should also adhere to this rule. In general, most of the timeouts in BLE seem to be 30 seconds - with the notable exception of link-layer procedures that are tied to a 60 seconds RX timeout.

RE: GATT Characteristic Read Timeout

Frederic — Thu, 27 Nov 2014 08:42:13 GMT

If the central device is a iOS or Andriod Smartphone, how long is the Read timeout at this Smartphones?

RE: GATT Characteristic Read Timeout

John — Wed, 26 Nov 2014 17:45:29 GMT

This holds true in the 4.1 specification as well. My initial thought would be that this is the SIG's way of telling stack developers that they need to put a timeout on the action, but that the timeout can be implementation dependent. Just a guess though.