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3 GATT Database file (gatt.xml)

This section of the document describes the XML syntax used in the Smart Profile Toolkit and walks

Bluetooth

you through the different options you can use when building Smart services and characteristics. A few

Bluetooth

practical GATT database examples are also shown.

3.1 Generic GATT Limitations

The following table lists limitations regarding GATT database.

Item BLE112, BLE113, BLE121LR and

BLED112

BT121

Maximum number of

characteristics

All characteristics which do not have

are counted in this

const="true"

All characteristics which do not have

are counted in this

const="true"

Maximum length of a

characteristic value

a type="user"

b const="true"

c const="false"

a Unlimited

b Available free flash

c 255 bytes

a 511 bytes

b Available free flash, up to 255 bytes

c Available free memory, up to 255 bytes

Maximum number of

attributes

in a single GATT

database

255 Limited by available free flash