5.7.2 Over-the-Air (OTA) DFU Procedure
The Over-the-Air (OTA) firmware upgrade is a protocol that allows Bluetooth Low Energy devices to receive a firmware image over the air from another Bluetooth Low Energy device. Microchip-defined OTA profile and service enables firmware upgrades over the Bluetooth Low Energy link using Generic Attribute Profile (GATT). The Bluetooth Low Energy OTA protocol defines the communication between the OTAU target and the OTAU manager. The OTAU manager can be a mobile device (iOS/Android™) or any Bluetooth Low Energy device that implements the OTA GATT client protocol that transfers the upgrade firmware to the OTAU target. The OTAU target implements the OTA GATT server protocol to receive the new firmware image.
This approach strictly recommends having a successful and secure Bluetooth Low Energy link connection between two devices. Here, a peer device (OTA client profile) initiates a DFU request to the remote device requesting a device firmware update. A status event %OTA_REQ% will be received at the RNBD451 device. In this case, the device with the OTA client profile can be considered a mobile device. The status event %OTA_REQ% will be sent to the host for its approval. Upon receiving the DFU update request, the RNBD451 has the task of accepting or rejecting the request.
The host can respond back with the OTAA,01 command to the RNBD451 if it wish to update the firmware. For the following procedure, there are several status events that will be followed from the RNBD451 to indicate the procedure step and DFU progressing status.
For the detail demo procedure, refer to the 8.2 OTA DFU Process.
