BLE reference API Response characteristic
Digi XBee® 3 Zigbee® RF Module
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API frames do not need to be written completely in a single write operation to the request
characteristic. In fact, Bluetooth limits the size of a written value to 3 bytes smaller than the
configured Maximum Transmission Unit (MTU), which defaults to 23, meaning that by default, you can
only write 20 bytes at a time.
After connecting you must send a valid Bluetooth Unlock API Frame in order to authenticate the
connection. If the BLE Unlock API - 0x2C frame has not been executed, all other API frames are silently
ignored and are not processed.
API Response characteristic
UUID: f9279ee9-2cd0-410c-81cc-adf11e4e5aea
Permissions: Readable, Indicate
Responses to API requests made to the request characteristic are returned through the response
characteristics. This characteristic cannot be read directly.
Response data is presented through indications on this characteristic. Indications are acknowledged
and re-transmitted at the BLE link layer and application layer and provide a robust transport for this
data.