Specifications

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supporting firmware must be in place to handle these file accesses. The generation of such
a module is beyond the scope and resources of this project. T herefore, file system code
must be obtained that will perform the appropriate memory operations. The code mus t be
conservative both in size and RAM usage.
3.3.3 Networking Layer
The Networking Layer is responsible for information routing between multiple devices in
a system. This could include a direct connection from a PC to a logger, a wireless connection
between multiple loggers, or a PC to Logger connection through the w ireless network. To
facilitate a common multiple interface layer, all compatible devices must therefore be able to
commu nicate using the propr itary Wrapped Acclima Serial Universal Protocol (WASUP).
WASUP contains a universal interface standard for use with serial RS-232, User Datagram
Protocol (UDP), and Transm ission Control Pr otocol (TCP). WASUP must be expanded to
incorporate the ZigBee interface. Any WASUP message must either be processed by any
recipient or sent to its appropriate destination.
3.3.4 Operating System Layer
The OS layer is responsible for system management and responsiveness. An OS can
be a complex piece of management co de exercising control over all system resources an d
dictating their access permissions. T he root of any OS is its scheduler. The scheduler is the
portion of the OS that dictates how to allocate the processor(s). Many sty les and methods
of schedu lers have been d eveloped to meet the needs of embedd ed system. Cooperative vs.
preemptive, dynamic vs. s tatic, priority vs. round robin, and table-based vs. link-list task
queues, just to name a few.
This device requires a sched uler that will be able to manage multiple operations or
tasks. The completion time of these tasks vary f rom less than 50ms to one minute. Af-
ter weighing the performance and size specifications of the existing OS platforms, it was
deemed that they either required too much memory to operate or provided services that
were un necessary for this device. Therefore, it was determined that a new OS would be