Multi-Tech MultiConnect mDot MTDOT Series, Developer'S Manual

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FOTA (FUOTA) OVERVIEW
MultiConnect
®
mDot
TM
MTDOT Developer Guide for Japan 13
Fragmentation
During this stage, the device should only send uplinks as necessary, too many can cause excessive fragment loss.
Applications on the device should not perform heavy processing activities during FOTA. Doing so can cause
fragments to overlap and excessive fragment loss. The number of fragments required to send a file depends on the
Data Rate. The device clears the file system to ensure enough free space to save update firmware and a backup
copy of the current firmware saved by the bootloader. User files are removed when the fragmentation session is
set up.
Parity
Multicast messages are unconfirmed meaning some loss of fragments is expected. The device can recover a certain
number of fragments though parity.