mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 771

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

Chapter 36
Carrier Modulator Transmitter (CMT)
36.1 Introduction
The carrier modulator transmitter (CMT) module provides means to generate the protocol
timing and carrier signals for a wide variety of encoding schemes. The CMT incorporates
hardware to off-load the critical and/or lengthy timing requirements associated with
signal generation from the CPU, releasing much of its bandwidth to handle other tasks
such as code data generation, data decompression, or keyboard scanning. The CMT does
not include dedicated hardware configurations for specific protocols but is intended to be
sufficiently programmable in its function to handle the timing requirements of most
protocols with minimal CPU intervention. When the modulator is disabled, certain CMT
registers can be used to change the state of the infrared output (CMT_IRO) signal
directly. This feature allows for the generation of future protocol timing signals not
readily producible by the current architecture.
36.2 Features
The features of this module include:
Freescale Semiconductor, Inc.
• Four modes of operation
• Extended space operation in time, baseband, and FSK modes
• Time; with independent control of high and low times
• Baseband
• Frequency shift key (FSK)
• Direct software control of CMT_IRO signal
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Preliminary
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