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Freescale Semiconductor
22-1
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
Chapter 22
Programmable Interrupt Timers (PIT0–PIT1)
22.1
Introduction
This chapter describes the operation of the two programmable interrupt timer modules: PIT0–PIT1.
22.1.1
Overview
Each PIT is a 16-bit timer that provides precise interrupts at regular intervals with minimal processor
intervention. The timer can count down from the value written in the modulus register or it can be a
free-running down-counter.
22.1.2
Block Diagram
Figure 22-1. PIT Block Diagram
22.1.3
Low-Power Mode Operation
This subsection describes the operation of the PIT modules in low-power modes and debug mode of
operation. Low-power modes are described in the power management module,
shows the PIT module operation in low-power modes and how it can exit from
each mode.
Internal Bus
Clock (f
sys/2
)
16-bit PMRn
16-bit PIT Counter
COUNT = 0
Internal Bus
16-bit PCNTRn
Internal Bus
EN
OVW
DOZE
DBG
Prescaler
PRE[3:0]
RLD
PIF
PIE
Load
Counter
To Interrupt
Controller
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60