Periodic Wakeup Module

The PWU is available in all modes of operation (run, wait, and stop) and performs two main functions:

• Generate periodic wakeup requests to bring the microcontroller unit (MCU) out of stop mode.
• Generate periodic interrupt requests during run and wait modes

Features of the periodic wakeup module include:

• Interrupt with separate interrupt enable bit, interrupt vector and interrupt mask bit
• Exit from low-power stop mode without external signals
• Programmable clock input
• Selectable timeout periods (40 µs to 3 minutes with an adjustment resolution of better than 1% for periods over 4 ms)
• Dedicated low-power 32 kHz internal oscillator separate from the main system clock sources
• Option to allow bus clock source to run the PWU
• Accessible in all modes of operation (run, wait, and stop).

Peripheral Initialization Components provide a low-level hardware approach to initialize registers of the peripheral module. They are intended for experienced users.