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Chapter 40 pulse frequency modulator, Pfm overview – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 40 Pulse Frequency Modulator

1.PFM Overview

Chapter 40 Pulse Frequency Modulator

This chapter provides an overview of the 16-bit pulse frequency modulator, describes the regis-
ter structure/functions, and describes the operation of the 16-bit pulse frequency modulator.

1. PFM Overview

The 16-bit pulse frequency modulator consists of two 16-bit down-counters, two 16-bit reload
registers, prescalers for generating the internal count clocks and control registers.

Functions

• Two independent programmable 16-bit down-counters generating low and high pulses.

• The input clock can be selected from prescaled internal clocks (the machine clock divided by 2/8/32/64/128)

separately for each counter.

• The mark level and output waveform can be inverted.