mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 795

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

Chapter 37
FlexTimer (FTM)
37.1 Introduction
The FlexTimer module is a two to eight channel timer which supports input capture,
output compare, and the generation of PWM signals to control electric motor and power
management applications. The FTM time reference is a 16-bit counter that can be used as
an unsigned or signed counter.
37.1.1 FlexTimer Philosophy
The FlexTimer is built upon a very simple timer (HCS08 Timer PWM Module – TPM)
used for many years on Freescales 8 bit microcontrollers. The FlexTimer extends the
functionality to meet the demands of motor control, digital lighting solutions and power
conversion yet providing low cost and backwards compatibility with the TPM module.
Several key enhancements are made: signed up-counter, dead time insertion hardware,
fault control inputs, enhanced triggering functionality and initialization and polarity
control.
All the features common with the TPM module have fully backwards compatible register
assignments and the FlexTimer can use code on the same core platform without change to
perform the same functions. A small exception to this is when the FlexTimer clock
frequency is twice bus clock frequency to provide extra resolution for high speed PWM
applications.
Motor control and power conversion features have been added through a dedicated set of
registers and defaults turn off all new features. The new features such as hardware dead
time insertion, polarity, fault control and masking greatly reduce loading on the execution
software and are usually each controlled by a group of registers.
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Preliminary
Freescale Semiconductor, Inc.
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