s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 223

• Manufacturer Part Number: s908az32ag2cfue
• Description: M68hc08 Microcontrollers 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Chapter 20
Programmable Interrupt Timer (PIT)
20.1 Introduction
This section describes the Programmable Interrupt Timer (PIT) which is a periodic interrupt timer whose
counter is clocked internally via software programmable options.
PIT.
20.2 Features
Features of the PIT include:
20.3 Functional Description
Figure 20-1
that can operate as a free-running counter or a modulo up-counter. The counter provides the timing
reference for the interrupt. The PIT counter modulo registers, PMODH–PMODL, control the modulo value
of the counter. Software can read the counter value at any time without affecting the counting sequence.
Freescale Semiconductor
•
•
•
Programmable PIT Clock Input
Free-Running or Modulo Up-Count Operation
PIT Counter Stop and Reset Bits
BUS CLOCK
INTERNAL
shows the structure of the PIT. The central component of the PIT is the 16-bit PIT counter
CSTOP
CRST
TIMPMODH:TIMPMODL
16-BIT COMPARATOR
16-BIT COUNTER
PRESCALER
Figure 20-1. PIT Block Diagram
MC68HC908AZ32A Data Sheet, Rev. 2
PPS2
PRESCALER SELECT
PPS1
PPS0
Figure 20-1
POIE
is a block diagram of the
POF
INTER-
LOGIC
RUPT
223