PXS20RM Datasheet, PDF (53/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Introduction
The RC oscillator provides these features:
• Nominal frequency 16 MHz
• ±5% variation over voltage and temperature after process trim
• Clock output of the RC oscillator serves as system clock source in case loss of lock or loss of clock
is detected by the FMPLL
• RC oscillator is used as the default system clock during startup and can be used as back-up input
source of FMPLL(s) in case XOSC fails
1.4.17 Clock, Reset, Power Mode, and Test Control Modules (MC_CGM,
MC_RGM, MC_PCU, and MC_ME)
These modules provide the following:
• Clock gating and clock distribution control
• Halt, stop mode control
• Flexible configurable system and auxiliary clock dividers
• Various execution modes
— Reset, Idle, Test, Safe
— Various RUN modes with software selectable powered modules
— No stand-by mode implemented (no internal switchable power domains)
1.4.18 Periodic Interrupt Timer Module (PIT)
The PIT module implements the following features:
• 4 general purpose interrupt timers
• 32-bit counter resolution
• Can be used for software tick or DMA trigger operation
1.4.19 System Timer Module (STM)
The STM implements the following features:
• Up-counter with 4 output compare registers
• OS task protection and hardware tick implementation per AUTOSAR¹ requirement
The STM is replicated for each processor.
1.4.20 Software Watchdog Timer (SWT)
This module implements the following features:
• Fault tolerant output
• Safe internal RC oscillator as reference clock
1.Open System Architecture
Freescale Semiconductor
PXS20 Microcontroller Reference Manual, Rev. 1
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