Motorola MCF5281 用户手册
MOTOROLA
Chapter 26. General Purpose I/O Module
26-3
Introduction
26.1.1 Overview
The MCF5282 ports module controls the configuration for various external pins, including
those used for:
those used for:
• External bus accesses
• Chip selects
• Debug data
• Processor status
• Ethernet data and control
• FlexCAN transmit/receive data
• I
• Chip selects
• Debug data
• Processor status
• Ethernet data and control
• FlexCAN transmit/receive data
• I
2
C serial control
• QSPI
• SDRAM control
• 32-bit DMA timers
• UART transmit/receive
• SDRAM control
• 32-bit DMA timers
• UART transmit/receive
26.1.2 Features
The MCF5282 ports includes these distinctive features:
• Control of primary function use on all ports
• Digital I/O support for all ports
• Digital I/O support for all ports
— Registers for storing output pin data
— Registers for controlling pin data direction
— Registers for reading current pin state
— Registers for setting and clearing output pin data registers
— Registers for controlling pin data direction
— Registers for reading current pin state
— Registers for setting and clearing output pin data registers
26.1.3 Modes of Operation
The operational modes for the MCF5282 ports are listed below. For more detailed
descriptions of each mode, refer to Section 26.4, “Functional Description.”
descriptions of each mode, refer to Section 26.4, “Functional Description.”
• Single-chip mode
All pins are configured as digital I/O by default, except for debug data pins
(DDATA[3:0]) and processor status pins (PST[3:0]).
(DDATA[3:0]) and processor status pins (PST[3:0]).
• Master mode
Ports A and B function as the upper external data bus. Ports C and D can function as
the lower external data bus. Ports E–J are configured to support external memory.
the lower external data bus. Ports E–J are configured to support external memory.