CCS/CC2640R2F: Peripheral request MTU size change

David Yau

Intellectual 510 points

Part Number: CC2640R2F

Tool/software: Code Composer Studio

Hi everyone,

Can the peripheral device request the MTU size change instead from the host?

If the host is Android device, we can do it from host, but in iOS, we don't find any related API.

I find GATT_ExchangeMTU, but the comment in gatt.h said it is used by the client(host)

Thank you!

Best regards

David

over 6 years ago

0 Evan W over 6 years ago

TI__Mastermind 39790 points

Hi David,

Only the GATT client (e.g central) can initiate an MTU exchange procedure.
e2e.ti.com/.../567320

However, the value of the MTU used is always negotiated to the minimum that the devices (master and slave) can support. If you set your peripheral to support the max MTU size, the phone and the peripheral will agree on that size. If you set it to smaller than the phone, you will find the connection negotiates to the smaller MTU.

I did find these discussions on Apples website and stack overflow that may be of use.
forums.developer.apple.com/.../73871
stackoverflow.com/.../ios-mtu-size-for-ble-data-transfer-between-ios-device-and-external-accessoryb

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CCS/CC2640R2F: Peripheral request MTU size change