mcf5272 Freescale Semiconductor, Inc, mcf5272 Datasheet - Page 66

• Manufacturer Part Number: mcf5272
• Description: Mcf5272 Coldfire Integrated Microprocessor User
• Manufacturer: Freescale Semiconductor, Inc

MCF5272-Specific Features
for chip select 0 (CS0), which is active after power-on reset until programmed otherwise.
BUSW1 and BUSW0 select the initial data bus width for CS0 only. A wake-up from sleep
mode or a restart from stop mode does not require reconfiguration of the chip select
registers or other system configuration registers.
1.4 MCF5272-Specific Features
This section describes features peculiar to the MCF5272.
1.4.1 Physical Layer Interface Controller (PLIC)
The physical layer interface controller (PLIC) allows the MCF5272 to connect at a physical
level with external CODECs and other peripheral devices that use either the general circuit
interface (GCI), or interchip digital link (IDL), physical layer protocols. This module is
primarily intended to facilitate designs that include ISDN interfaces.
1.4.2 Pulse-Width Modulation (PWM) Unit
The PWM unit is intended for use in control applications. With a suitable low-pass filter, it
can be used as a digital-to-analog converter. This module generates a synchronous series of
pulses. The duty cycle of the pulses is under software control.
Its main features include the following:
The PWM implements a simple free-running counter with a width register and comparator
such that the output is cleared when the counter exceeds the value of the width register.
When the counter wraps around, its value is not greater than the width register value, and
the output is set high. With a suitable low-pass filter, the PWM can be used as a
digital-to-analog converter.
1.4.3 Queued Serial Peripheral Interface (QSPI)
The QSPI module provides a serial peripheral interface with queued transfer capability. It
supports up to 16 stacked transfers at a time, making CPU intervention between transfers
unnecessary. Transfer RAMs in the QSPI are indirectly accessible using address and data
registers. Functionality is similar to the QSPI portion of the QSM (queued serial module)
implemented in the MC68332.
1-8
• Double-buffered width register
• Variable-divide prescale
• Three identical, independent PWM modules
• Byte-wide width register provides programmable control of duty cycle.
MCF5272 User’s Manual
MOTOROLA