CC2640: Cannot receive ATT_MTU_UPDATED_EVENT

Choongbeom You

Expert 1700 points

Part Number: CC2640

Hello, I'm using ble_sdk_2_02_05_02 for my device.

I set the MAX_PDU_SIZE to 255 and test with iPhone 12 pro.

I can see the MTU exchange req/rsp in the packet log but cannot receive the ATT_MTU_UPDATED_EVENT in my application.

exchange_mtu_test_iphone.zip

I disabled DLE in build_config.opt file. Is it enabled for ATT_MTU_UPDATED_EVENT?

/* -DBLE_V42_FEATURES=SECURE_CONNS_CFG+EXT_DATA_LEN_CFG */
-DBLE_V42_FEATURES=SECURE_CONNS_CFG

Thanks,

Calvin

over 5 years ago

0 Clément over 5 years ago

TI__Guru** 101540 points

Hi Calvin,

Could you verify a couple of elements for me?

- What is the MTU before the update is attempted?

- Do you receive the ATT_MTU_UPDATED_EVENT if you y to update the MTU with a different value? Would be nice to see which values lead to the reception of a ATT_MTU_UPDATED_EVENT and which values do not.

- Do you receive all the other GATT events? Have you the line "GATT_RegisterForMsgs(selfEntity);" in your code?

Best regards,

0 Choongbeom You over 5 years ago in reply to Clément

Expert 1700 points

Hi Clément,

GATT_RegisterForMsgs was missing. It works now.

Thank you very much.

0 Clément over 5 years ago in reply to Choongbeom You

TI__Guru** 101540 points

Hi Calvin,

These are good news! Thank you for your patience.

May I kindly ask you to mark as resolved the other threads dealing with this issue?

Thanks and regards,

Bluetooth®︎

Bluetooth forum

CC2640: Cannot receive ATT_MTU_UPDATED_EVENT