MC9RS08KA2 Datasheet, PDF (87/132 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 11
Modulo Timer (RS08MTIMV1)
11.1 Introduction
The MTIM is a simple 8-bit timer with several software selectable clock sources and a programmable
interrupt.
The central component of the MTIM is the 8-bit counter that can operate as a free-running counter or a
modulo counter. A timer overflow interrupt can be enabled to generate periodic interrupts for time-based
software loops.
The TCLK input is connected to the PTA2 pin of the MC9RS08KA2 Series. The XCLK input is connected
to the ICSFFCLK clock divided by two, where the ICSFFCLK is the fixed-frequency internal reference
clock from the ICS module.
Figure 11-1 shows the MC9RS08KA2 Series block diagram with the MTIM highlighted.
RS08 CORE
BDC
CPU
RS08 SYSTEM CONTROL
RESET AND STOP WAKEUP
MODES OF OPERATION
POWER MANAGEMENT
RTI
COP
WAKEUP
LVD
5-BIT KEYBOARD
INTERRUPT MODULE
(KBI)
ANALOG COMPARATOR
MODULE
(ACMP)
MODULO TIMER
MODULE
(MTIM)
5
ACMP+
ACMP-
TCLK
ACMPO
PTA0/KBIP0/ACMP+ ⁽¹⁾
PTA1/KBIP1/ACMP- ⁽¹⁾
PTA2/KBIP2/TCLK/RESET/V_PP ^{(1),( 2)}
PTA3/ACMPO/BKGD/MS
PTA4/KBIP4 ^(1),(3)
PTA5/KBIP5 ^{(1), (3)}
USER FLASH
MC9RS08KA2 — 2048 BYTES
MC9RS08KA1 — 1024 BYTES
USER RAM — 63 BYTES
INTERNAL CLOCK
SOURCE
(ICS)
V_SS
POWER AND
V_DD
INTERNAL REGULATOR
NOTES:
(1) Pins are software configurable with pullup/pulldown device if input port.
(2) Integrated pullup device enabled if reset enabled (RSTPE=1).
(3) These pins are not available in 6-pin package
Figure 11-1. MC9RS08KA2 Series Block Diagram Highlighting MTIM Block and Pins
MC9RS08KA2 Series Data Sheet, Rev. 2
Freescale Semiconductor
87