Specifications

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Fig. 3.1: Depiction of the general hardware design.
and to verify correct device operation. This requirement coupled with the memory
card requirement allows an operator to forgo u sing a computer to download data and
adjust device settings. The other way is through the PC software. This software
should be able to interface to a logger or a network of loggers and be designed to
database the data collected by all nodes in a given sys tem.
Good design practice dictates the use of separation of concerns and simp lification or elab-
oration of requirements in the design to achieve a solution that meets all the above stated
requirements. The rest of this chapter will discuss in detail how the design specifics were
defined through analysis and elimination.
3.2 Hardware Platform Breakdown
Figure 3.1 gives a high level modular d ecomposition of the logger hardware. Modularity
helps minimizes the impact of design changes by iterative revisions through localizing the
impact of ch an ges to individual mod ules. Each module is required to be as self-contained as
possible. A module’s interface is restricted to simple interface points, through which data
exchange occurs. There is a common power bus for the entire logger that is not represented