AN413 Datasheet, PDF (1/45 Pages) STMicroelectronics – Initialization of the ST9

AN413
Application note
Initialization of the ST9
1
Introduction
The ST9 family offers the microprocessor designer a wide variety of architectural features
configurable to the user’s specific application requirements. Central to all these
configurations is a multiple register based microcomputer core to which may be added on-
chip, powerful peripheral components including A/D converters, Serial Communication
Interface units (SCIs), and 16-bit Multifunction timers with input capture/output compare
capabilities. The availability, on-chip, of these application-specific units obviates the need for
external interface design as well as offering high-speed and good reliability.
The particular peripherals incorporated on-chip may themselves be individually configured
to offer a wide variety of functional (architectural) alternatives. This configuration is typically
implemented by simple software routines included in the power-on- or system- reset
routines. The sole difficulty which the user may initially encounter stems, in fact, from the
power and versatility of this approach to system design. The large number of available
options means that the user must specify a large number of system parameters by
initializing control register contents for the specific peripheral units.
The objective of this Application Note is to suggest to the user a programming structure and
philosophy to aid in the initial configuration of the system. The approach is illustrated by a
number of specific examples selected from the wide range available for the ST9030,
ST9040 families, but are applicable to all ST9s.
November 2011
Doc ID 1875 Rev 2
1/45
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