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PMM Operation
2.2.7 PMM Interrupts
Interrupt flags generated by the PMM are routed to the system NMI interrupt vector generator register,
SYSSNIV. When the PMM causes a reset, a value is generated in the system reset interrupt vector
generator register, SYSRSTIV, corresponding to the source of the reset. These registers are defined
within the SYS module. More information on the relationship between the PMM and SYS modules is
available in the SYS chapter.
2.2.8 Port I/O Control
The PMM provides a means of ensuring that I/O pins cannot behave in uncontrolled fashion during an
undervoltage event. During these times, outputs are disabled, both normal drive and the weak pullup or
pulldown function. If the CPU is functioning normally, and then an undervoltage event occurs, any pin
configured as an input has its PxIN register value locked when the event occurs, until voltage is restored.
During the undervoltage event, external voltage changes on the pin are not registered internally. This
helps prevent erratic behavior from occurring.
65
SLAU272C – May 2011 – Revised November 2013
Power Management Module and Supply Voltage Supervisor
Copyright © 2011–2013, Texas Instruments Incorporated