QN9080 cannot send more than 20 bytes through QPP service. Is there any way to increase it?

[cicerodomingosj]

Hello everybody,

I would like to know how to increase QPP tx packet size. I tried to increase the value length in the characteristic declaration but does not affect the transmission: sending data with length above 20 bytes appears no arrives in the client.

Any idea?

[estephania_mart]

Hello,

Could you please refer to this post ?

How to increase MTU size b/w qn9080 and Android 

Regards,
Estephania

[cicerodomingosj]

Hello Estephania,

Thanks.

The following steps were taken to resolve:

- Increased MTU size to 192 bytes in ble_constants.h, below to max ATT size found in Bluetooth 4.2 specification;

- Increased characteristic value size in gatt_db.h;

- Increased max payload size (CFG_MAX_MPS) to 192 bytes in qn_ble_config.h;

- On Android application, after BLE connect event, negotiate a new MTU size (mBluetoothGatt.requestMtu(MTUSIZE));

After these steps, exchange data with 192 bytes becomes possible.

Regards,

Cicero

[estephania_mart]

it is good that you solve it.

Regards ,

Estephania