2 device initial conditions after system reset, Software initialization – Texas Instruments MSP430x4xx User Manual
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System Reset and Initialization
2-4
System Resets, Interrupts, and Operating Modes
2.1.2
Device Initial Conditions After System Reset
After a POR, the initial MSP430 conditions are:
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The RST/NMI pin is configured in the reset mode.
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I/O pins are switched to input mode as described in the Digital I/O chapter.
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Other peripheral modules and registers are initialized as described in their
respective chapters in this manual.
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Status register (SR) is reset.
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The watchdog timer powers up active in watchdog mode.
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Program counter (PC) is loaded with address contained at reset vector
location (0FFFEh). CPU execution begins at that address.
Software Initialization
After a system reset, user software must initialize the MSP430 for the
application requirements. The following must occur:
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Initialize the SP, typically to the top of RAM.
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Initialize the watchdog to the requirements of the application.
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Configure peripheral modules to the requirements of the application.
Additionally, the watchdog timer, oscillator fault, and flash memory flags can
be evaluated to determine the source of the reset.