MTU exchange failing with error 0x0e

RE: MTU exchange failing with error 0x0e

Kenneth — Wed, 11 Dec 2024 14:09:18 GMT

Hi,

[quote user="Gaurav2908"]Can you please explain why would this config solve this issue[/quote]

My theory is that those that wrote the LL of the central device have not properly tested and supported this use case. There is nothing illegal done by the peripheral device, it just the central device that is not able to handle it.

Kenneth

RE: MTU exchange failing with error 0x0e

Gaurav — Wed, 11 Dec 2024 13:48:04 GMT

Hi Kenneth

Adding -

CONFIG_BT_GATT_AUTO_SEC_REQ=n

CONFIG_BT_GATT_AUTO_UPDATE_MTU=n

Is giving satisfactory results in initial testing.

Can you please explain why would this config solve this issue

RE: MTU exchange failing with error 0x0e

Kenneth — Wed, 11 Dec 2024 13:05:08 GMT

Hello,

In general I see from time to time that central devices "misbehave" if the peripheral device try to initiate specific procedures upon connection. This is fully allowed by the BLE spec, but somehow some of them still don't handle it very well. The typical ones I can find are:

CONFIG_BT_GATT_AUTO_SEC_REQ=y
CONFIG_BT_AUTO_DATA_LEN_UPDATE=y
CONFIG_BT_AUTO_PHY_UPDATE=y
CONFIG_BT_GATT_AUTO_UPDATE_MTU=y

Setting either or all to =n should not be problematic, because in my experience all central devices will do this in any case in their own pace.

Best regards,
Kenneth