s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 207

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

Chapter 19
Timer Interface Module B (TIMB)
19.1 Introduction
This section describes the timer interface module (TIMB). The TIMB is a 2-channel timer that provides a
timing reference with input capture, output compare and pulse width modulation functions.
a block diagram of the TIMB.
19.2 Features
Features of the TIMB include:
19.3 Functional Description
Figure 19-1
can operate as a free-running counter or a modulo up-counter. The TIMB counter provides the timing
reference for the input capture and output compare functions. The TIMB counter modulo registers,
TBMODH–TBMODL, control the modulo value of the TIMB counter. Software can read the TIMB counter
value at any time without affecting the counting sequence.
The two TIMB channels are programmable independently as input capture or output compare channels.
19.3.1 TIMB Counter Prescaler
The TIMB clock source can be one of the seven prescaler outputs or the TIMB clock pin, PTD4/ATD12.
The prescaler generates seven clock rates from the internal bus clock. The prescaler select bits, PS[2:0],
in the TIMB status and control register select the TIMB clock source.
Freescale Semiconductor
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Two Input Capture/Output Compare Channels
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Buffered and Unbuffered Pulse Width Modulation (PWM) Signal Generation
Programmable TIMB Clock Input
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Free-Running or Modulo Up-Count Operation
Toggle Any Channel Pin on Overflow
TIMB Counter Stop and Reset Bits
Rising-Edge, Falling-Edge or Any-Edge Input Capture Trigger
Set, Clear or Toggle Output Compare Action
7 Frequency Internal Bus Clock Prescaler Selection
External TIMB Clock Input (4 MHz Maximum Frequency)
shows the TIMB structure. The central component of the TIMB is the 16-bit TIMB counter that
MC68HC908AZ32A Data Sheet, Rev. 2
Figure 19-1
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is